Universidad del Norte (Colombia)
  • Barranquilla, Atlántico, Colombia
Recent publications
Rapid urbanization trends and urban lifestyles challenge urban populations to recognize ecosystems’ contributions to their well-being, and urban planners to integrate nature at the core of urban development. This study assesses the relationships between ecosystems and people in the rapidly expanding Barranquilla Metropolitan Area (BMA) and extracts lessons for its planning as a BiodiverCity. Using 22 interviews and 400 face-to-face surveys we evaluated: 1) the perception of positive and negative contributions of specific types of ecosystems to human well-being (HWB); 2) the importance and vulnerability of multiple ecosystem services (ES) and disservices (EdS); and 3) the relationships between ES, EdS and relational values (RV), and the influence of socioeconomic factors in providing HWB, using a Structural Equation Model (SEM). Open-ended answers in the survey showed that rural and certain natural ecosystems, such as wetlands, mangroves and tropical dry forest were the least valued ecosystems and included some EdS. In contrast, urban and peri-urban ecosystems, namely the river, beaches, crops, urban green, and backyards, were the most valued. Overall, regulating ES were perceived as critical, as well as important and vulnerable. The results of the SEM model indicate that HWB is not only explained by socioeconomic factors such as income and education, but also by ES. We argue that the necessary sustainable socio-economic development of the BMA should be coupled with an urban planning that integrates ES and their contributions to HWB.
Background Sustainable production and consumption are two important issues, which mutually interact. Whereas individuals have little direct influence on the former, they can play a key role on the latter. This paper describes the subject matter of sustainable consumption and outlines its key features. It also describes some international initiatives in this field. Results By means of an international survey, the study explores the emphasis given to sustainable consumption during the second wave of the COVID-19 pandemic, and the degree of preparedness in individuals to engage in the purchase of green and sustainably manufactured products. The main results indicate that the pandemic offered an opportunity to promote sustainable consumption; nevertheless, the pandemic alone cannot be regarded as a ‘game changer’ in this topic. Conclusions Apart from an online survey with responses from 31 countries, which makes it one of the most representative studies on the topic, a logit model was used to analyse the main variables that affect the probability of pro-environmental consumption behaviour because of the COVID-19 pandemic. The paper lists some of the technological and social innovations that may be needed, so as to guide more sustainable consumption patterns in a post-pandemic world.
Diverse litter studies on Colombia's Central Caribbean Coast have presented the Microplastic issues regarding typology, magnitudes, and distribution. No studies have examined MPs' presence and abundances in relation to sediment grain size and the sediments statistical parameters (mean, median, sorting, skewness, kurtosis). This work attempts to fill this information gap in a study of 15 sampling sites along Colombia's Central Caribbean Coast. Sediment samples were collected and analysed to determine sediment granulometric properties, in association with the presence, magnitudes, shapes, and impact of MPs, and their possible relationships. Within the study area, grain size distribution was similar between surveyed sites, with a dominance of three textural groups: sands, slightly gravelly sands, and slightly gravelly muddy sands. In terms of size-sorting categories, the percentages were moderately well sorted (60 %), moderately sorted (20 %), well sorted (13 %), and very well sorted (7 %). Microplastic abundances (densities) ranged from 160 to 1120 MPs/kg, similar to other global beaches. Microplastic fibers were the dominant typology at 86.8 % of the combined beaches total. Multiple linear regression analysis suggested that approximately 30 % of the MPs' presence could be related to changes in the five sediment statistics used in this work, being the most important statistical parameter sorting with 11 % (r2 = 0.27 - F-Statistic = 0.67). To manage the MP issue, reducing the current elevated plastic inputs into the environment is necessary/mandatory. Approaches to reach this goal must be focused on the entire plastic life cycle (extraction, design, production, use, disposal, recovery, recycling).
Although walkability assessments have enjoyed recent popularity, walkability measures usually often omitted microscale attributes and pedestrian perceptions of the built environment. Generally, walkability measures rely on mesoscale attributes because of their ease of measurement. Walkability indices that combine built environment mesoscale and microscale characteristics are relatively new and have not yet been applied to assess the walkability of an entire city. Rather than focusing on the merits of such an index, this article reports the walkability assessment of all street segments in Bogotá (Colombia), highlighting differences in perceptions among pedestrian types and the uneven quality of pedestrian infrastructure throughout the city. Our results show significant differences were found according to socioeconomic level and age range. However, that preferences for the subjective factors and observable components of walkability are similar by gender. We recommend estimating and adapting indices to represent better local conditions, including microscale attributes and different pedestrian types’ perceptions of the built environment. This methodology is a useful tool for policy-making, as it identifies suitable segments and zones for interventions that improve pedestrian network conditions and also estimates their effect on walkability according to probable changes to the microscale factors according to the pedestrian type.
Attention deficit/hyperactivity disorder (ADHD) is the most common childhood neurodevelopmental disorder. Single nucleotide polymorphisms (SNPs) in the Adhesion G Protein-Coupled Receptor L3 (ADGRL3) gene are associated with increased susceptibility to developing ADHD worldwide. However, the effect of ADGRL3 non-synonymous SNPs (nsSNPs) on the ADGRL3 protein function is vastly unknown. Using several bioinformatics tools to evaluate the impact of mutations, we found that nsSNPs rs35106420, rs61747658, and rs734644, previously reported to be associated and in linkage with ADHD in disparate populations from the world over, are predicted as pathogenic variants. Docking analysis of rs35106420, harbored in the ADGLR3-hormone receptor domain (HRM, a common extracellular domain of the secretin-like GPCRs family), showed that HRM interacts with the Glucose-dependent insulinotropic polypeptide (GIP), part of the incretin hormones family. GIP has been linked to the pathogenesis of diabetes mellitus, and our analyses suggest a potential link to ADHD. Overall, the comprehensive application of bioinformatics tools showed that functional mutations in the ADGLR3 gene disrupt the standard and wild ADGRL3 structure, most likely affecting its metabolic regulation. Further in vitro experiments are granted to evaluate these in silico predictions of the ADGRL3-GIP interaction and dissect the complexity underlying the development of ADHD.
Durability has become a valuable design aspect for designers, manufacturers, service providers, and end-of-life actors. Nowadays, developing products for new business models based on renting and servitization practices is of paramount importance. Furthermore, durability enables the application of circularity strategies for product lifespan extension, including reuse, repair, refurbish, and remanufacture. However, despite the growing trend around durability, there is no precise tracing of its evolution, implementation, and potential benefits from the product design stage. Therefore, this article aims to analyze the existing literature about durability and its relationship with the circular economy concept starting from the product design process, uncovering potential research directions, challenges, and trends for its application. A total of 147 articles were selected and analyzed from 40 years of research using two main approaches. First, a keyword-based analysis was used to identify trending topics around the concept of durability. Second, a content-based analysis was used, encompassing four main aspects: objectives and methodology; actors involved and lifecycle phases; circular economy strategies; and design phase, design attributes, and type of products involved. The analysis identified how the concept has evolved during the last four decades, indicating that future trends envisage methodologies, assessment tools, and guidelines to support product life extension.
We are celebrating two years of officially launching Global Rheumatology, the new scientific journal for PANLAR. During this time, the emerging publication has consolidated its editorial policy with differential characteristics that meet the needs of promotion and communication of knowledge of the rheumatology community worldwide, especially in Latin America.
Background Urinary incontinence (UI) is the inability to completely control the process of releasing urine. UI presents a social, medical, and mental issue with financial consequences. Objective This paper proposes a framework based on machine learning for predicting urination time, which can benefit people with various degrees of UI. Method A total of 850 data points were self-recorded by 51 participants to investigate how different factors impact urination time. The participants were instructed to record input data (such as the time of consumption and the number of drinks) and output data (i.e., the time the individual urinated). Other factors, such as age and BMI, were also considered. The study was conducted in two phases: (1) data was prepared for modeling, including missing values, data encoding, and scaling; and (2) a classification model was designed with four output classes of the next urination time: < = 30 min, 31–60 min, 61–90 min, > 90 min. The model was built in two steps: (1) feature selection and (2) model training and testing. Feature selection methods such as lasso regression, decision tree, random forest, and chi-square were used to select the best features, which were then used to train an extreme gradient boosting (XGB) algorithm model to predict the class of the next urination time. Result The feature selection steps resulted in nine features considered the most important features affecting UI. The accuracy, precision, recall, and F1 score of the XGB predictive model are 0.70, 0.73, 0.70, and 0.71, respectively. Conclusion This research is the first step in developing a machine learning model to predict when a person will need to urinate. A precise predictive instrument can enable healthcare providers and caregivers to assist people with various forms of UI in reliable, prompted voiding. The insights from this predictive model can allow future apps to go beyond current UI-related apps by predicting the time of urination using the most relevant factors that impact voiding frequency.
We investigate exact solutions and the asymptotic dynamics for the Friedmann–Lemaître–Robertson–Walker universe with nonzero spatial curvature in the fourth‐order modified teleparallel gravitational theory known as f(T,B)$$ f\left(T,B\right) $$ theory. We show that the field equations admit a minisuperspace description, and they can reproduce any exact form of the scale factor. Moreover, we calculate the equilibrium points and analyze their stability. We show that Milne and Milne‐like solutions are supported, and the de Sitter universe is provided. To complete our analysis, we use Poincaré variables to investigate the dynamics at infinity.
This paper introduces skew dihedral group rings and their applications for public-key cryptography. We present a specific skew group ring that is the underlying algebraic platform for our cryptographic constructions. We then build a two-party key exchange protocol and present an analysis of its security. We then exploit it to derive a group key agreement protocol, a probabilistic public-key scheme, and a key encapsulation mechanism. In addition to the security analysis of our cryptographic constructions, we present a proof-of-concept implementation.
According to the ambidexterity literature, organizations tend to favor either exploration or exploitation activities. However, few studies have elucidated why this imbalance occurs, what the ideal balance is, and how to remedy any disparities between what organizations tend to do and what they should do. This study addresses this paucity by situating these questions in the context of environmental conditions (static or dynamic) and organizational conditions (simple or complex) through a strategic fit paradigm lens. We systematically reviewed 20 years of exploration–exploitation research and developed an empirically grounded, contextually relevant framework that describes four organizational archetypes: the Kangaroo, Lion, Mouse, and Camel archetypes. We found that it often makes sense for organizations to be off-balance and identified the factors that cause imbalance and the strategies that managers can employ to manipulate the exploration–exploitation mix according to their organizations’ specific archetypes. By incorporating all three questions and delineating between organizational archetypes, this systematic review brings together the fragmented literature and provides a novel framework for advancing research and influencing managerial practice.
The aim of this paper is to derive a separable entropy for a one-dimensional reduced blood flow model, which will be used to treat the symmetrizability of the model in full generality and for constructing entropy conservative fluxes, which are one of the essential building blocks of designing entropy-stable schemes. Time discretization is conducted by implicit–explicit (IMEX) Runge–Kutta schemes, but solutions for nonlinear systems will not be required due to the particular form of the source term. To validate the numerical schemes obtained, some numerical tests are presented.
In the present paper, we report the observations of field emission (FE) from silicon nanowires array (Si-NWsA) synthesized on p-type Si (100) using wet chemical etching (WCE) approach, confirmed by XPS and XRD spectra. The luminescence band has been studied from the photoluminescence spectroscopy reveals the red shifting band. Here, optical spectra dependent Brus model is employed to calculate the quantum size of Si-NWsA, which is comparable to the Bohr radius of Si-NWsA, indicates the confined size. Moreover, the crystal size of Si-NWsA is calculated using theoretical bond polarizability (BP) model using Raman spectra. Experimental FE data are studied in the Fowler Nordheim (F-N) framework to estimate the field enhancement factor and turn-on voltage. Moreover, theoretical Flip model has been used for the estimation of field enhancement factor. The field enhancement factor for a Si-NWsA is calculated to be as high as 1329.8 due to its small radius tip.
Sociosexuality refers to an individual’s disposition to have casual sex without establishing affective bonds and has been widely studied worldwide using the Revised Sociosexual Orientation Inventory (SOI-R; Penke & Asendorpf, 2008). Despite its many validations in different cultural contexts, no psychometric analyses of this instrument have been conducted in Spanish-speaking Latin American countries. To address this gap in the literature, we examined the psychometric properties of the SOI-R in Colombia. In a cross-sectional study with a large sample of participants (N = 812; 64% women), we conducted exploratory and confirmatory factor analyses to identify different factor structures and determine which had the best fit for our sample and examined the reliability of the scale. Results showed that a three-factor structure, with sociosexual behaviors, attitudes, and desire as first-order factors, and global sociosexuality as a second-order factor, had the best fit indexes. Each factor presented good reliability indexes. Replicating already established gender differences, we also found that men scored higher on each factor when compared to women. These findings show that the SOI-R is a reliable and valid instrument to assess sociosexuality in countries where sociosexuality research is underrepresented.
As many business activities—especially those associated with the energy-intensive industries—continue to be major sources of greenhouse gas emissions, and hence significantly contributing to global warming, there is a perceived need to identify ways to make business activities eventually carbon neutral. This paper explores the implications of a changing climate for the global tourism business and its intertwining global aviation industry that operates in a self-regulatory environment. Adopting a bibliometric analysis of the literature in the domain of global tourism and climate change (772 articles), the paper reveals the underlying sustainability issues that entail unsustainable energy consumption. The aviation industry as a significant source of carbon emission within the sector is then examined by analyzing the top 20 largest commercial airlines in the world with respect to its ongoing mitigating measures in meeting the Paris Agreement targets. While self-regulatory initiatives are taken to adopt Sustainable Aviation Fuels (SAF) as alternative fuel production and consumption for drastically reducing carbon emission, voluntary alignment and commitment to long-term targets remain inconsistent. A concerted strategic approach to building up complementary sustainable infrastructures among the global network of airports based in various international tourist destination cities to enable a measurable reduction in carbon emission is necessary to achieve a transformational adaptation of a business sector that is of essence to the recovery of the global economy while attempting to tackle climate change in a post-COVID-19 era.
During installation of driven or jacked piles in sand, particle crushing occurs in a region below the base of these piles. Quantification of the degree and extent of particle crushing during driving or jacking in sand is necessary to improve current design methods. To study the effects of particle crushing on the capacity of piles jacked in uniform silica sand samples, a model pile was jacked and tested in a half-cylindrical calibration chamber with transparent observation windows in its front wall. Annular samples of crushed sand 3 mm in thickness were recovered after testing from several locations along the shaft and the base of the model piles and used to assess particle gradation changes and to calculate breakage parameters. Relationships between the load mobilized at the base of the model piles and three breakage parameters are proposed. Furthermore, the number of jacking strokes (ranging from 1 to 32 in this research) has a negligible effect on the degree of crushing produced during installation and on the measured stresses at the base of the model pile. Analyses of the digital images captured during pile jacking indicate that the silica sand particles in the path of the model pile crush mainly along irregularities and sharp edges. Different zones are identified below the model pile according to the degree of particle crushing. Digital images taken during static loading of the model pile allowed tracking of the displacement paths of individual sand particles during loading.
This study examined the prevalence and risk factors associated to victimization by caregivers in a national large sample of Chilean children and adolescents. 19,687 children and adolescents aged 12–17, selected by random probability sampling of 699 public schools in Chile who were surveyed by trained interviewers. Victimization by Caregivers was evaluated through a module of the Juvenile Victimization Questionnaire (JVQ). The prevalence (12 months) for physical abuse were (12.9%), for emotional abuse (27.9%), neglect (5.3%) and parental interference (3.5%). The results suggest as risk factors, sex, age, migration status, disability, geographical location, and type of school. The findings highlight the urgent need to address the issue of child maltreatment and victimization by caregivers in Chilean society and minimize its impact.
The aquatic macrophyte Eichhornia crassipes has great potential for the control of Hg pollution in the environment. The aim of this study was to investigate the capability of E. crassipes to accumulate elemental mercury (Hg0). The plants were exposed for 30 days to 5, 10, 20, 40, and 80 mg of Hg0 in a 1-L Hoagland medium with the Hg0 settled at the bottom of the flask. The roots of the plants did not touch the mercury during the treatment. After exposure, the total Hg (T-Hg) concentrations in the roots, leaves, and stems were measured using a direct mercury (Hg) analyzer. The highest concentrations were found at 80 mg Hg0 treatment in the roots, leaves, and stems, in that order. The translocation factor indicated a poor capability of Hg to translocate from the roots to the shoots. The relative growth and the root-length inhibition measurements showed that the differences between Hg0 treatments were not significant. In addition, the treatments negatively affected the chlorophyll concentration. The carotenoid content was found to be significantly different at 20 and 40 mg of Hg0 in 1 L. Regarding the carbonyl index in root proteins, significant differences compared to control were found at the highest Hg treatment. Based on these results, it was shown that E. crassipes is able to take up elemental Hg from Hoagland medium. However, the Hg0 treatments did not show a strong stress-response activation mechanism in the evaluated plant tissues.
Institution pages aggregate content on ResearchGate related to an institution. The members listed on this page have self-identified as being affiliated with this institution. Publications listed on this page were identified by our algorithms as relating to this institution. This page was not created or approved by the institution. If you represent an institution and have questions about these pages or wish to report inaccurate content, you can contact us here.
5,016 members
Carlo V Caballero-Uribe
  • Department of Medicine
Jorge Acosta-Reyes
  • Department of Public Health
Sandra Melendez-Labrador
  • Department of Social Communication
Dayana Agudelo-Castañeda
  • Department of Civil and Environmental Engineering
Km.5 Vía Puerto Colombia, 081007, Barranquilla, Atlántico, Colombia
Head of institution
Adolfo Meisel
(57) (5) 3509509