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- ÍtemAcceso Abierto004 - A Novel Familial Case of Diffuse Leukodystrophy Related to NDUFV1 Compound Heterozygous Mutations(2013-07-30) Rivera-Nieto, C.; Mateus, H.; Ortega-Recalde, O.; Fonseca Mendoza, Dora Janeth; Patiño, L.; Restrepo Fernández, Carlos Martín; Van der Knaap, M.; Laissue, P.Introduction: Mitochondrial leukodystrophy due to complex I deficiency is an entity with high genetic heterogeneity, the mutations of the gene NDUFV1 being one of the causes of this disease. It is an autosomal recessive entity that causes a variable phenotype, from a fatal neonatal onset to neurodegenerative disorders in adulthood. Problem Studied: We report 2 siblings, 5 and 2 years of age, with nystagmus, ataxia, impaired consciousness, hemiparesis, hyporeflexia, and psychomotor regression. In brain magnetic resonance imaging, signal abnormalities in large regions of the cerebral white matter were observed, suggesting a demyelinating disease. Materials and Methods: Genomic DNA was obtained from whole blood. The complete coding region of NDUFV1 was amplified in patients and their parents. Each amplicon was purified. Direct sequencing was performed. Intron 6 and exon 7 amplicons from patient 1 were cloned. A skin biopsy was performed in the mother. RNA was isolated. The NDUFV1 complementary DNA (cDNA) was amplified and directly sequenced. In silico analysis was performed. Following diagnosis, treatment with ubiquinol and riboflavin was started. Results: Both patients have the missense mutation c.1156C> T and the 42-base pair deletion in the gene NDUFV1. Bioinformatics analysis indicates that this deletion leads to messenger RNA (mRNA) synthesis with a premature stop codon. Probably, mutant mRNAs were recognized and degraded by the nonsense-mediated mRNA machinery. Analysis of the maternal NDUFV1 cDNA supports this hypothesis. Conclusion: Our results add information on the molecular basis and the phenotypic features of mitochondrial disease caused by NDUFV1 mutations. We can affirm that the mutations are causative of the phenotype. The patients are having a good therapeutic response to the treatment.
- ÍtemSolo Metadatos344 Point of Care Ultrasonography Training in Bogotá Emergency Medicine Residencies: The Unmet Need(2012-10) Henwood, P.C.; Norwood, B.R.; Genthon, A.A.; Silva, D.; Martinez, Y.B.; Granada, J.; Torres, J.; Romero, M.G.; Arbelaez, C.Background: As ultrasonography equipment has evolved toward increased portability, higher quality and lower cost, the field of point-of-care ultrasonography has grown, with numerous applications for emergency medicine practitioners. Competence in goal-directed ultrasonography image acquisition and interpretation is now a mandatory part of emergency medicine residency training in the United States and the United Kingdom. Appropriate training is a key component to the safe and effective use of this technology. In Colombia, emergency medicine is a relatively new specialty and leaders in the field have expressed interest in further integrating pointof-care ultrasonography into emergency medicine practice and resident training. Study Objectives: The objective of this study was to conduct a needs assessment to better understand the current state of point-of-care ultrasonography practice among all emergency medicine residency programs in Bogotá, Colombia. Methods: An ultrasonography needs assessment survey tool was distributed to all available residents of the 3 emergency medicine residency programs in Bogotá. The emergency medicine program directors, other physicians staffing the emergency departments, and several medical students rotating in the emergency departments were also surveyed. The needs assessment survey tool assessed the population’s experience with point-of-care ultrasonography, formal ultrasonography education, and interest in educational initiatives. Focus group sessions with 50% of emergency medicine residents in Bogotá were subsequently conducted to further qualify their perspective on the current state of diagnostic ultrasonography at each residency training site as it relates to their clinical and procedural practice. Partners Health care institutional review board exemption was obtained for this research. Results: Fifty four total clinicians (43 emergency physicians, 5 non-emergency physicians and 6 medical students) completed the survey. Twenty-nine participants (54%) had previously used an ultrasonography machine. Of all emergency medicine respondents, 24 had used ultrasonography, and trauma was the most common application. However, 52% of those who had used ultrasonography had performed less than 10 independent scans. Thirty-nine participants (72%) had received no formal ultrasonography training. Of respondents, 94% total (100% of emergency physicians) reported a high level of interest in learning point-of-care ultrasonography, particularly trauma and vascular access applications. The major barriers identified by those surveyed were the absence of teachers (83%), the absence of ultrasonography equipment (65%), and time limitations (39%). Focus group discussions revealed that the scope of clinical practice, especially regarding procedures performed by emergency physicians, varied between emergency departments and residencies, but all reported they wanted more training in the use of point-of-care ultrasonography to improve their practice and patient care. Conclusion: Emergency ultrasonography training and use in clinical practice among emergency medicine residencies in Bogotá is currently limited by the lack of ultrasonography equipment and educators. However, there is significant interest in educational initiatives among all residents and program directors. Further research into how to best integrate point-of-care ultrasonography into emergency medicine practice and resident training in Colombia is needed.
- ÍtemSolo MetadatosA Biomechanical Analysis of Free Squat Exercise Employing Self-Organizing Maps(2019) Blanco Diaz C.F.; Katerine Quitian González A.; Isaza S.J.; Orjuela Cañón, Alvaro DavidWith the current employment of visualization tools, different techniques may be used to understand multivariable information. This document presents an alternative method for the analysis of biomechanical phenomena, presenting the knee joint execution of free squat exercise. For this, the MaxTRAQ software and the open-source and cross-platform software Mokka were employed. A system of cameras allowed to digitize the movements. Then, with the use of Self-Organizing Maps tasks of visualization and clustering were developed for multivariate data. Results showed that this tool allows finding nonlinear relations between the analyzed input variables and outputs, when the data treatment demands an extra-work because of its dimensionality. © 2019 IEEE.
- ÍtemSolo MetadatosA column generation approach for solving a green bi-objective inventory routing problem(2016) Franco Franco, Carlos Alberto; López-Santana E.R.; Méndez-Giraldo G.The aim of this paper is present a multi-objective algorithm embedded with column generation to solve a green bi-objective inventory routing problem. In contrast with the classic Inventory Routing Problem where the main objective is to minimize the total cost overall supply chain network, in the green logistics besides this objective a minimization of the CO2emisions is included. For solving the bi-objective problem, we proposed the use of NISE (Noninferior Set Estimation) algorithm combined with column generation for reduce the amount of variables in the problem. © Springer International Publishing AG 2016.
- ÍtemSolo MetadatosA comprehensive cybersecurity audit model to improve cybersecurity assurance: The cybersecurity audit model (CSAM)(2018) Sabillon R.; Serra-Ruiz J.; Cavaller V.; Cano J.Nowadays, private corporations and public institutions are dealing with constant and sophisticated cyberthreats and cyberattacks. As a general warning, organizations must build and develop a cybersecurity culture and awareness in order to defend against cybercriminals. Information Technology (IT) and Information Security (InfoSec) audits that were efficient in the past, are trying to converge into cybersecurity audits to address cyber threats, cyber risks and cyberattacks that evolve in an aggressive cyber landscape. However, the increase in number and complexity of cyberattacks and the convoluted cyberthreat landscape is challenging the running cybersecurity audit models and putting in evidence the critical need for a new cybersecurity audit model. This article reviews the best practices and methodologies of global leaders in the cybersecurity assurance and audit arena. By means of the analysis of the current approaches and theoretical background, their real scope, strengths and weaknesses are highlighted looking forward a most efficient and cohesive synthesis. As a resut, this article presents an original and comprehensive cybersecurity audit model as a proposal to be utilized for conducting cybersecurity audits in organizations and Nation States. The CyberSecurity Audit Model (CSAM) evaluates and validates audit, preventive, forensic and detective controls for all organizational functional areas. CSAM has been tested, implemented and validated along with the Cybersecurity Awareness TRAining Model (CATRAM) in a Canadian higher education institution. A research case study is being conducted to validate both models and the findings will be published accordingly. © 2017 IEEE.
- ÍtemSolo MetadatosA distance measure between fuzzy variables(2017) Figueroa-García J.C.; López-Santana E.R.; Franco Franco, Carlos AlbertoThis paper shows some distance measures based on memberships and centroids for comparing fuzzy variables which are commonly used in fuzzy logic systems and rule-based models. An application example is provided, and some interpretation issues are explained. © 2017, Springer International Publishing AG.
- ÍtemSolo MetadatosA fuzzy inference system to scheduling tasks in queueing systems(2017) López-Santana E.R.; Franco Franco, Carlos Alberto; Figueroa-Garcia J.C.This paper studies the problem of scheduling customers or tasks in a queuing system. Generally the customers or a set of tasks in queuing system are attended according with different rules as round robin, equiprobable, shortest queue, among others. However, the condition of the system like the work in process, utilization and the length of queue is difficult to measure. We propose to use a fuzzy inference system in order to determine the status in the system depended of input variables like the length queue and the utilization. The experiment results shows an improvement in the performance measures compared with traditional scheduling policies. © Springer International Publishing AG 2017.
- ÍtemAcceso AbiertoA fuzzy linear fractional programming approach to design of distribution networks(2018) López-Santana E.; Franco Franco, Carlos Alberto; Figueroa-García J.C.This paper studies the distribution network design problem considering the uncertain information in the demand, capacities, costs and prices in a multi-product environment and multiple periods. We consider a fractional objective function that consist in maximize the ratio between total profit and total cost. We use a model that integrates a facility location problem with a distribution network problem with fuzzy constraints, technological coefficients, and costs. To solve the problem, we use a method that transform the fuzzy linear fractional programming model in an equivalent multi-objective linear fractional programming problem to calculate the upper, middle and lower bounds of the original problem. © 2018, Springer Nature Switzerland AG.
- ÍtemSolo MetadatosA graph based characterization of functional resting state networks for patients with disorders of consciousness(2015) Martínez, Darwin E.; Martinez, Johann H.; t, Jorge E. Rudas; Demertzi, Athena; Heine, Lizette; Tshibanda, Luaba; Soddu, Andrea; Laureys, Steven; Gomez, FranciscoDisorder of consciousness (DOC) is a consequence of severe brain injuries. Diagnosis of DOC is very challenging because it requires the patient collaboration. Research in hemodynamic brain activity in resting state conditions suggests that healthy brain is organized into large-scale resting state networks (RSNs) of sensory/cognitive relevance. Recently, relationships among these RSNs have been explored as a possible biomarker of loss of consciousness. The RSN functional connectivity is computed as the temporal relationship between pairs of RSNs time-courses. It results in the so called functional network of brain connectivity (FNC). The properties of this network in the DOC conditions remains poorly understood. In this work, we investigated some local complex network properties of the brain FNC, during altered states of consciousness. For this, we characterized a population of 49 DOC patients and 27 healthy controls. fMRI data was acquired and processed for each subject to built a FNC for each one. Network characterization was performed by computing the strength and the clustering coefficient measurements at individual level on the corresponding FNC. These nodal measurements allows to understand brain alterations of single RSN in the FNC. Our results show that strength and clustering variations may reflect brain network reconfiguration, and they may be associated to loss of consciousness states in patients with DOCs. © 2015 IEEE.
- ÍtemSolo MetadatosA hybrid rule-based and fuzzy logic model to diagnostic financial area for MSMEs(2018) Giraldo G.M.; López-Santana E.; Franco Franco, Carlos AlbertoThe importance of the micro, small and medium enterprises (MSMEs) in the regional and global economy causes the academic community to worry about its development and growth that is why several institutions publics and privates have advanced studies about problems of these organizations. We present a diagnostic model based on Rules which works together with the fuzzy logic. Our model allows to determine the possible diseases that suffer in financial matters as well as to determine their gravity and to offer alternative solutions. © Springer International Publishing AG, part of Springer Nature 2018.
- ÍtemSolo MetadatosA lightweight deep learning model for mobile eye fundus image quality assessment(2020) Pérez A.D.; Perdomo Charry, Oscar Julián; González F.A.Image acquisition and automatic quality analysis are fundamental stages and tasks to support an accurate ocular diagnosis. In particular, when eye fundus image quality is not appropriate, it can hinder the diagnosis task performed by experts. Portable, smart-phone-based eye fundus image acquisition devices have the advantage of their low cost and easy deployment, however, their main disadvantage is the sacrifice of image quality. This paper presents a deep-learning-based model to assess the eye fundus image quality which is small enough to be deployed in a smart phone. The model was evaluated in a public eye fundus dataset with two sets of annotations. The proposed method obtained an accuracy of 0.911 and 0.856, in the binary classification task and the three-classes classification task respectively. Besides, the presented method has a small number of parameters compared to other state-of-the-art models, being an alternative for a mobile-based eye fundus quality classification system. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.
- ÍtemAcceso AbiertoA Mathematical Model Under Uncertainty for Optimizing Medicine Logistics in Hospitals(2018) Franco Franco, Carlos Alberto; López-Santana E.R.; Figueroa-García J.C.Managing resources in hospitals is one of the most challenging duties in healthcare. The complexity of supply chain management in hospitals is high due to different factors such as life cycle of medicines, demand uncertainty, variation of prices, monetary resources, space constraints, among others. The main important factor of the supply chain in hospitals is the welfare of patients which depends of the correct management and administration of medicines, in this way backorders or stockouts are not allowed. In this paper we propose a mathematical model to make real planning over a health care supply chain considering real factors face by decision makers. For testing results we have used real data considering different sources of uncertainty. We have choose 5 different types of medicines and run the optimization model to determine the optimal solution over a set of scenarios generated for modeling uncertainty. For testing the results, we have compare over a year planning the results obtained by our policy and the results obtained by the hospital, improving the results in terms of costs. © 2018, Springer Nature Switzerland AG.
- ÍtemSolo MetadatosA New Automatic Cancer Colony Forming Units Counting Method(2019) Roldán N.; Rodriguez L.; Hernandez A.; Cepeda K.; Ondo Méndez, Alejandro Oyono; Cancino Suárez S.L.; Forero M.G.; Lopéz J.M.Clonogenic assays are an essential tool to evaluate the survival of cancer cells that have been exposed to a certain dose of radiation. Its result can be used in the generation of strategies for the optimization of radiotherapy treatments. The analysis of this type of data requires that the specialist performs the manual counting of colony forming units (CFU), i.e., find every cell that retains the ability to produce a large progeny. This task is time consuming, prone to errors and the results are not reproducible due to specialist subjective assessment. Digital image processing tools can deal with the flaws described above. This article presents a new technique for automatic CFU counting. The proposed technique extracts the regions of interest (ROIs), where a local segmentation algorithm finds and labels the CFUs in order to quantify them. Results show good sensitivity and specificity performance compared to state-of-the-art software used for CFU detection and counting. © 2019, Springer Nature Switzerland AG.
- ÍtemSolo MetadatosA new proposal of quality indicators for clinical engineering: A New Beginning for Human Health: Proceedings of the 25th Annual International Conference of the IEEE Engineering in Medicine and Biology Society(2003-01-01) Miguel Cruz, Antonio; Rodriguez, E.; Sanchez, M.C.; Tolkmitt, F.; Pozo, E.As we know from Stiefels paper '...we want to do our work right the first time and better the next time. But we really don't know whether we have done it right, or are doing it better, unless we have a measurement system for quality.' Unfortunately, there is little agreement in the standardization of indicators used for evaluation of organizations related to medical equipment management. And those that do the first steps, always walk on thin ice. With this paper, we suggest a set of five quality indicators for the control and the evaluation of management for medical equipment maintenance. The indicators proposed allow the organization, that applies them, to easily correct and adjust their management programs, with a strive for improvement in results and quality and broadening their experiences. The selection of the indicators was executed according to those that are most used among leading health care organizations. Sometimes the indicators are labeled differently but the basic idea is the same, and therefore the results can be compared competitively and the potential of an organization can be displayed.
- ÍtemSolo MetadatosA note about the (x, y) coordinates of the centroid of a fuzzy set(2018) Figueroa-García J.C.; López-Santana E.R.; Franco Franco, Carlos AlbertoThis paper presents some considerations about the centroid of a fuzzy set, where the y-coordinate (or vertical centroid) is defined and discussed. An interesting fact about the y-centroid is analyzed using some results for Gaussian, triangular, and non-convex fuzzy sets. Some considerations about the obtained results are provided and some recommendations are given. © 2018, Springer Nature Switzerland AG.
- ÍtemSolo MetadatosA polynomial-time attack on the BBCRS scheme(2015) Couvreur, Alain; Otmani, Ayoub; Tillich, Jean-Pierre; Gauthier-Umaña, ValérieThe BBCRS scheme is a variant of the McEliece public-key encryption scheme where the hiding phase is performed by taking the inverse of a matrix which is of the form T + R where T is a sparse matrix with average row/column weight equal to a very small quantity m, usually m and lt; 2, and R is a matrix of small rank z ? 1. The rationale of this new transformation is the reintroduction of families of codes, like generalized Reed-Solomon codes, that are famously known for representin insecure choices. We present a key-recovery attack when z = 1 and m is chosen between 1 and 1+R+O(1/?n) where R denotes the code rate. This attack has complexity O(n6) and breaks all the parameters suggested in the literature. © International Association for Cryptologic Research 2015.
- ÍtemSolo MetadatosA preliminary approach to identify the best function that fits the growth of company total assets(2018) Juárez, FernandoTotal Assets define companies; it is relevant in determining the size of the companies, ranking them by economic relevance and making predictions about their future. That makes necessary to analyze how companies growth, according to Total Assets, so this research problem focuses on identifying what the trend in Total Assets growth is across industries and company size categories, to find similarities and differences. Accordingly, the purpose of the study is to analyze the Total Assets company growth finding a function that fits across industries and company size categories. The method is analytical, deductive and empirical; it is a cross-sectional analysis with two industries and four different company sizes, based on Total Assets grouped into the categories of micro, small, medium or big enterprise. Every combination of industry-company size is analyzed to see which function draws the best fit. The functions are: 1) Linear, 2) Logarithmic, 3) Inverse, 4) Quadratic, 5) Cubic, 6) Compound, 7) Power, 8) S, 9) Growth, 10) Exponential, and 11) Logistic. The test consists of a regression analysis. ANOVA significance test and explained variance allow identifying the best function fit. Results show that cubic function gives the best results in all industry-company size combination. Other functions are relevant in some, but not all, combinations of categories. The conclusion is that cubic function provides the best fit to total assets company growth across several industry-company size combinations. However, it requires more in deep analysis and replication of the research in other industries to confirm the results. © 2018 IEEE.
- ÍtemSolo MetadatosA three-step deep neural network methodology for exchange rate forecasting(2017) Figueroa-García J.C.; LóPez-Santana E.; Franco Franco, Carlos AlbertoWe present a methodology for volatile time series forecasting using deep learning. We use a three-step methodology in order to remove trend and nonlinearities from data before applying two parallel deep neural networks to forecast two main features from processed data: absolute value and sign. The proposal is successfully applied to a volatile exchange rate time series problem. © Springer International Publishing AG 2017.
- ÍtemSolo MetadatosA two-phase method to periodic vehicle routing problem with variable service frequency(2018) López-Santana E.; Franco Franco, Carlos Alberto; Giraldo G.M.This paper presents a method to solve the periodic vehicle routing problem with service frequency. The problem consists in finding a set of paths for a crew of vehicles to deliver products or services to a set of customers in a discrete planning horizon subject to constraints as vehicle capacity, distance-time constraints, time windows, and the variable demand that implies a not defined frequency. Our method solves iteratively two mixed integer programming models. The first one assigns customers to be visited on the planning horizon. The second finds paths to visit the customers for each period. However, in case of non-feasibility a set of rules modify the allocation and the process starts again until the solution is obtained. We present an example to illustrate the method. © Springer International Publishing AG, part of Springer Nature 2018.
- ÍtemSolo MetadatosAB0354 Subcutaneous abatacept in patients with rheumatoid arthritis: A real-life experience(2016-06) Sarmiento-Monroy, J.C.; Villota-Eraso, C.; Mantilla-Ribero, M.J.; Molano González, Nicolás; Rodríguez Jiménez, Mónica María del Pilar; Rojas-Villarraga, A.; Mantilla, R.D.Background Therapeutic guidelines draw heavily on evidence from randomized controlled trials undertaken in well-characterized, highly-selective populations and managed in tightly-controlled settings. As such, the extent to which therapeutic efficacy in real-life populations and routine care settings is often unclear