Abstract: Because only limited research has been done on base geometry effects on pile base resistance, design methods used in practice for full-displacement, partial-displacement, and non-displacement piles in sand do not consider these effects on base resistance calculations. In this paper, the effect of base geometry on pile resistance is studied by performing a series of tests in a half-cylindrical calibration chamber that allows observation of the sand domain through the chamber symmetry plane during installation and loading. Two model piles, one with a flat base and one with a conical base with an apex angle of 60°, were installed and load-tested in dense and medium dense sand samples. Digital images taken during loading of the model piles were processed using the Digital Image Correlation (DIC) technique. Detailed displacement and strain fields obtained with the DIC technique and base resistance measurements demonstrate that the addition of a conical base to a pile changes the deformation pattern in the sand below the base during loading. Furthermore, the base resistances of both the jacked and pre-installed model piles with a conical base were less than those for the piles with flat base for the same conditions, with the corresponding ratio ranging from 0.64 to 0.78 at relative displacement levels less than or equal to 10% of the diameter B of the model pile and from 0.70 to 0.84 at greater relative displacements. The results have implications also for the use of cone resistance from cone penetration test (CPT) in pile base resistance estimation. Resumen: Debido a que solo se ha realizado una investigación limitada sobre los efectos de la geometría de la base en la resistencia de la base del pilote, los métodos de diseño utilizados en la práctica para pilotes de desplazamiento total, desplazamiento parcial y sin desplazamiento en arena no consideran estos efectos en los cálculos de resistencia de la base. En este trabajo se estudia el efecto de la geometría de la base sobre la resistencia del pilote mediante la realización de una serie de ensayos en una cámara de calibración semicilíndrica que permite la observación del dominio de arena a través del plano de simetría de la cámara durante la instalación y carga. Se instalaron dos pilotes modelo, uno con base plana y otro con base cónica con un ángulo de vértice de 60 °, y se sometieron a prueba de carga en muestras de arena densa y medianamente densas. Las imágenes digitales tomadas durante la carga de los pilotes se procesaron utilizando la técnica de Correlación de imagen digital (DIC). Los campos detallados de desplazamiento y deformación obtenidos con la técnica DIC y las mediciones de resistencia de la base demuestran que la adición de una base cónica a un pilote cambia el patrón de deformación en la arena debajo de la base durante la carga. Además, las resistencias de la base tanto de los pilotes instalados mediante un jacking system y los pilotes preinstalados con base cónica fueron menores que las de los pilotes con base plana para las mismas condiciones, con la relación correspondiente que variaba de 0,64 a 0,78 a niveles de desplazamiento relativo menores que o igual al 10% del diámetro B del pilote y de 0,70 a 0,84 a mayores desplazamientos relativos. Los resultados también tienen implicaciones para el uso de la resistencia del cono obtenida de la prueba de penetración del cono (CPT) en la estimación de la resistencia de la base del pilote.

Abstract: Este artículo analiza el impacto de la política costarricense de apoyo al turismo sostenible, y en particular con el sistema de Certificación para la Sostenibilidad Turística (CST) del Instituto Costarricense de Turismo (ICT) en la innovación en servicios, procesos, mercadeo y organización de las empresas hoteleras del país. Se indagaron las causas y motivaciones para hacer cambios e introducir nuevos atributos dentro de la empresa. En la primera fase, se condujo encuestas con el 27% de todos los hoteles con declaratoria turística en Costa Rica y el 48% de los certificados con CST, para investigar los determinantes de la innovación y de la búsqueda de la certificación de sostenibilidad. Se aplicaron herramientas estadísticas para analizar diferencias entre los hoteles con y sin CST, así como la correlación de los determinantes de la innovación con el grado de innovación. Posteriormente se entrevistaron a seis hoteleros de diversos tipos para profundizar sobre las innovaciones realizadas, los determinantes y motivaciones. Los resultados indican que la certificación es un instrumento para ayudar a los gerentes a mejorar sustancialmente sus empresas, en términos de servicios, procesos, estructura interna y ahorros en agua y energía. Los hoteles con CST demuestren una tasa de ocupación 8% más alto que los hoteles no certificados, con un valor de p=0,01. No se evidenció una diferencia en innovación en mercadeo entre los hoteles con y sin CST.

Abstract: Land disputes between indigenous communities and peasants in Colombia are not something new. The scenario is almost the same: aboriginal communities conflicting with peasants and farmers for a territory in which to live. The issue has not been completely explored. In fact, analysis regarding territorial conflicts between indigenous peoples and farmers in Colombia remains insufficient because it is conservative when criticizing the institutional approaches to the conflict; it does not consider international examples; and what is worse, it lacks objectivity because the author usually takes a position in the conflict (commonly pro-indigenous). The specific case that I chose to study in this paper takes place in the northeast region of Colombia known as Catatumbo. The Barí peoples are an aboriginal group who have disputed farmer’s claims since the 1990s, in an effort to secure their property titles. The land dispute reached such magnitude that it was studied by the Colombian Constitutional Court in 2017. However, after many attempts to solve the territorial dispute, the problem persists. In this article, I explore alternative approaches to land disputes between farmers and native communities in Colombia. First, I give a general characterization of the conflict itself and the parties involved. Next, I present the existing theoretical and legal framework to approach the land dispute, emphasizing my research in the disparity between the rights of indigenous peoples and peasants regarding land access. Also, I argue that the existing institutional framework is naively biased to favor indigenous claims over farmers' demands. Finally, I compare examples from Common Law countries that could be useful to approach proportionality tests differently.

Abstract: The effort of universities, companies, and the state in Colombia to face home-made AP landmines has generated useful solutions and studies for many projects developed in the last decade, including demining processes in Colombia. Antipersonnel mines have changed in the last 15 years, due to the intermittent nature of our internal conflict. For example, as Descontamina Colombia mentions on its website, non-state armed groups cut the detonator containing the primary explosive to decrease the metal in the mine. This paper shows the aspects of the conflict that have affected humanitarian demining in Colombia, which help in the design and construction of technological devices. This article does not attempt to describe each of the typical technologies in humanitarian demining processes, but rather to show the characteristics considered in the design of two detection devices aimed at detecting home-made AP landmines.

Abstract: BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder associated with significant morbidity and mortality that may affect over 5% of children and approximately 2.8% of adults worldwide. Pharmacological and behavioral therapies for ADHD exist, but critical symptoms such as dysexecutive deficits remain unaffected. In a randomized, sham-controlled, double-blind, crossover mechanistic study, we assessed the cognitive and physiological effects of transcranial direct current stimulation (tDCS) in 40 adult patients with ADHD in order to identify diagnostic (cross-sectional) and treatment biomarkers (targets). METHODS: Patients performed three experimental sessions in which they received 30 minutes of 2 mA anodal tDCS targeting the left dorsolateral prefrontal cortex, 30 minutes of 2 mA anodal tDCS targeting the right dorsolateral prefrontal cortex, and 30 minutes of sham. Before and after each session, half the patients completed the Eriksen flanker task and the other half completed the stop signal task while we assessed behavior (reaction time, accuracy) and neurophysiology (event-related potentials). RESULTS: Anodal tDCS to the left dorsolateral prefrontal cortex modulated cognitive (reaction time) and physiological (P300 amplitude) measures in the Eriksen flanker task in a state-dependent manner, but no effects were found in the stop signal reaction time of the stop signal task. CONCLUSIONS: These findings show procognitive effects in ADHD associated with the modulation of event-related potential signatures of cognitive control, linking target engagement with cognitive benefit, proving the value of eventrelated potentials as cross-sectional biomarkers of executive performance, and mechanistically supporting the statedependent nature of tDCS. We interpret these results as an improvement in cognitive control but not action cancellation, supporting the existence of different impulsivity constructs with overlapping but distinct anatomical substrates, and highlighting the implications for the development of individualized therapeutics.

Abstract: In this study, a model assisted strategy is developed to control the distribution of colloids in porous media in the framework of nanoremediation, an innovative environmental nanotechnology aimed at reclaiming contaminated aquifers. This approach is exemplified by the delivery of humic acid-stabilized iron oxide nanoparticles (FeOx), a typical reagent for in situ immobilization of heavy metals. By tuned sequential injections of FeOx suspensions and of solutions containing a destabilizing agent (i.e. calcium or magnesium), the two fronts, which advance at different rates, overlap at the target location (i.e., the central portion) of the porous systems. Here, the particles deposit and accumulate irreversibly, creating a reactive zone. An analytical expression predicting the position of the clustering zone in 1D systems is derived from first principles of advective-dispersive transport. Through this equation, the sequence and duration of the injection of the different solutions in the medium is assessed. The model robustness is demonstrated by its successful application to various systems, comprising the use of different sands or immobilizing cations, both in 1D and 2D geometries. The method represents an advancement in the control of nanomaterial fate in the environment, and could enhance nanoremediation making it an effective alternative to more conventional techniques. Resumen: En este estudio, una estrategia modelística es desarrollada con el fin de controlar la distribución de coloides en medios porosos en el marco de la nanorremediación, una nanotecnología ambiental enfocada a la recuperación de acuíferos contaminados. En el presente análisis, se usan de nanopartículas de óxido de hierro estabilizadas con ácido húmico (FeOx), un reactivo típico para la inmovilización in situ de metales pesados. Mediante aplicaciones secuenciales controladas de suspensiones de FeOx y soluciones que contienen un agente desestabilizador (calcio o magnesio), los dos frentes, que avanzan a diferentes velocidades, se superponen en la ubicación deseada (en este caso en el centro) del medio porosos. Aquí, las partículas se depositan y acumulan de forma irreversible, creando una zona reactiva. Una expresión analítica que predice la posición de la zona de deposición en sistemas unidimensionales (1D) se deriva de los primeros principios del transporte advectivo-dispersivo. A través de esta ecuación se evalúa la secuencia y duración de la inyección de las diferentes soluciones en el medio poroso. La robustez del modelo se demuestra con la exitosa aplicación en diversos sistemas, que comprenden el uso de diferentes tamaños de grano o cationes inmovilizadores, tanto en geometrías 1D como 2D. El método representa un avance en el control del destino final de los nanomateriales en el medio ambiente y podría mejorar la nanorremediación, convirtiéndolo en una alternativa eficaz a las técnicas convencionales actuales.

Abstract: Cornelia de Lange Syndrome (CdLS) is an autosomal dominant (NIPBL, SMC3 and RAD21) or X-linked (SMC1A and HDAC8) disorder, characterized by distinctive craniofacial appearance, growth retardation, intellectual disability and limb anomalies. Its clinical presentation can be extremely variable. Here we report on a girl with classical CdLS phenotype, growth retardation, intellectual disability and gastroesophageal reflux disease, who is mosaic for the c.6647A>C mutation in the NIPBL gene. While this mutation was undetected by standard Sanger sequencing, it was identified by subsequent exome and panel sequencing approaches. Allele quantification by pyrosequencing showed the presence of the mutation in about 10%, 23.5% and 46.5% of DNA samples from peripheral blood leukocytes, buccal epithelial cells and fibroblasts, respectively. NIPBL mutations in a mosaic state are a frequent cause of CdLS, but clinical diagnosis of these patients can be challenging. In our case, the panel enriched sequencing as well as the exome sequencing clearly demonstrated to be very sensitive tools for mosaic mutation detection.

Abstract: Although the analysis of urban poverty has advanced towards the integration of objective and subjective approaches to assessing urban development, evaluation of quality of life in cities remains tied to a commodity framework which conceptualises it as the mere dotation of urban amenities. Multidimensional indicators of quality of life attempt to overcome this sort of restriction by considering broader informational spaces to assess well-being in cities. The capability approach has gone some way in addressing this as a multidimensional approach, however the interpretation of spatial phenomena has been absent from its application, meaning that the role of space in the configuration of urban poverty has been neglected. Drawing on cross-sectional data, this paper examines a multidimensional measure of urban poverty based on capabilities of young adults in Bogota in order to identify clusters of deprivation and affluence of well-being and determine levels of urban segregation based on this type of metric. The result is a spatialised index of capabilities that allow us to assess well-being from a perspective of socio-spatial differences. The findings support the importance of considering spatial patterning of capabilities in understanding poverty dynamics in cities. Spatialised capabilities may help to support urban policy design and promote greater understanding of spatial inequalities in cities.

Abstract: QoL studies conceptualise urban well-being as a multidimensional process that is influenced by personal and environmental factors. A much less explored field in QoL has to do with the notion of capabilities and functionings as measurements to evaluate the level of quality of life that people experience in cities. By investigating the young adults category, this article develops a measurement of QoL based on the normative framework of the Capability Approach (CA) to capture urban domains that affect quality of life in Bogota. This study introduces a quantitative methodology to use secondary aggregated data to build a QoL measurement based on capabilities. A nonlinear categorical principal component analysis was used to explore the underlying factor structure of a calibration sample (n=6,998). Confirmatory Factor Analysis was conducted to validate identified factors, revealing a good fit (SRMR=0.033, CFI=0.910). The result is a Young Adult Capability Index (YACI) that empirically explores the use of capability achievements as a space for evaluating urban QoL in young adults. A multiple linear regression was calculated to predict YACI based on additional variables which are sensitive to inequality for young adults. Results show that capability scores are lower once young adults enter adulthood. Women arrive with better capabilities from childhood and adolescence than men, but rapidly undergo a marked process of decapitalisation of capabilities during their transition to adulthood, suggesting the need for more attention in the elaboration of public policies for this type of population.

Abstract: Objective: To investigate opportunities for task shifting to decongest an outpatient neurology clinic in Zambia by describing current patient flow through the clinic and potential nodes for intervention using process mapping. Background: Zambia has a population of approximately 18 million people with 4 full-time adult neurologists, as of 2018, who all practice at the University Teaching Hospital (UTH), the main tertiary care center in the country. As a result of this provider-to-patient ratio, the outpatient neurology clinic is overcrowded and overbooked. Task-shifting programs have shown to improve efficiency, access and quality of care through the use of less specialized healthcare workers in low- and middle-income countries (LMIC). Methods: We evaluated patient flow in the UTH neurology outpatient clinic through the development and analysis of a process map. The characteristics of the clinic population between 2014 and 2018 were retrospectively reviewed from the clinic register. Between July and August 2018, we prospectively collected appointment lag times and time each patient spent waiting at various points in the clinic process. We conducted interviews with clinic staff and neurologists to generate a detailed process map of current pathways to care within the clinic. We then devised task- shifting strategies to help reduce patient wait times based on the overview of clinic process mapping and patient demographics. Results: From 2014 to 2018, there were 4701 outpatients seen in the neurology clinic. The most common neurologi- cal diagnoses were epilepsy (39.2%), headache (21.5%) and cerebrovascular disease (16.7%). During prospective data collection, patients waited an average of 57.8 (SD 73.4) days to be seen by a neurologist. The average wait time from arrival in the clinic to departure was 4.0 (SD 2.5) h. The process map and interviews with clinic staff revealed long waiting times due to a paucity of providers. Nurses and clerks represent an influential stakeholder group, but are not actively involved in any activity to reduce wait times. A large proportion of follow-up patients were stable and seen solely to obtain medication refills. Conclusions: Epilepsy, headache, and stroke make up the largest percentage of outpatient neurological illness in Zambia. Targeting stable patients in these diagnostic categories for a task-shifting intervention may lead to substan- tially decreased patient wait times. Potential interventions include shifting clinical follow-ups and medication refills to less specialized healthcare workers.