Complexity Reduction in Analyzing Independence between Statistical Randomness Tests Using Mutual Information.

The advantages of using mutual information to evaluate the correlation between randomness tests have recently been demonstrated. However, it has been pointed out that the high complexity of this method limits its application in batteries with a greater number of tests. The main objective of this work is to reduce the complexity of the method based on mutual information for analyzing the independence between the statistical tests of randomness. The achieved complexity reduction is estimated theoretically and verified experimentally. A variant of the original method is proposed by modifying the step in which the significant values of the mutual information are determined. The correlation between the NIST battery tests was studied, and it was concluded that the modifications to the method do not significantly affect the ability to detect correlations. Due to the efficiency of the newly proposed method, its use is recommended to analyze other batteries of tests.

Complejidades de la atención anestésica de urgencia en el anciano

El envejecimiento es un largo proceso de carácter universal propio de los seres vivos. Es notorio su crecimiento a nivel de la población mundial y no resulta exclusivo para los países desarrollados. El paciente anciano presenta grandes retos debido a las alteraciones propiciadas por el proceso de envejecimiento, que se acompaña de disminución de la capacidad de respuesta con deterioro en grado desigual de una serie de funciones morfofisiológicas, psicológicas y bioquímicas. Por otra parte, la atención médica a pacientes portadores de afecciones quirúrgicas de urgencia desata desafíos al equipo de trabajo ante la necesidad de brindar al enfermo una asistencia con un mínimo de preparación, lo que conlleva identificar estado de salud en un periodo de tiempo aceptable, lograr una estabilización previa al acto quirúrgico y favorecer una recuperación satisfactoria. Por tales razones, se realizó esta revisión bibliográfica con el propósito de resaltar una serie de factores que acompañan el proceso de envejecimiento y sus implicaciones para el proceder anestésico.

Aging is a universal nature long process, typical of living beings. Its growth at the world population level is notorious and it is not exclusive to developed countries. The elderly patient presents great challenges due to the alterations caused by the aging process, which is accompanied by decreased response capacity with uneven deterioration of a series of morphophysiological, psychological and biochemical functions. On the other hand, medical care for patients with urgent surgical conditions unleashes challenges for the work team due to the need to provide the patient with assistance with a minimum of preparation, which entails identifying a state of health in an acceptable period of time, achieve stabilization prior to the surgical act and favor a satisfactory recovery. For these reasons, this bibliographical review was carried out to highlight a series of factors that take part in the aging process and its implications for the anesthetic procedure.

On the Fitness Functions Involved in Genetic Algorithms and the Cryptanalysis of Block Ciphers.

There are many algorithms used with different purposes in the area of cryptography. Amongst these, Genetic Algorithms have been used, particularly in the cryptanalysis of block ciphers. Interest in the use of and research on such algorithms has increased lately, with a special focus on the analysis and improvement of the properties and characteristics of these algorithms. In this way, the present work focuses on studying the fitness functions involved in Genetic Algorithms. First, a methodology was proposed to verify that the closeness to 1 of some fitness functions' values that use decimal distance implies decimal closeness to the key. On the other hand, the foundation of a theory is developed in order to characterize such fitness functions and determine, a priori, if one method is more effective than another in the attack to block ciphers using Genetic Algorithms.

Accessible location of mobile labs for COVID-19 testing.

In this study, we address the problem of finding the best locations for mobile labs offering COVID-19 testing. We assume that people within known demand centroids have a degree of mobility, i.e., they can travel a reasonable distance, and mobile labs have a limited-and-variable service area. Thus, we define a location problem concerned with optimizing a measure representing the accessibility of service to its potential clients. In particular, we use the concepts of classical, gradual, and cooperative coverage to define a weighted sum of multiple accessibility indicators. We formulate our optimization problem via a mixed-integer linear program which is intractable by commercial solvers for large instances. In response, we designed a Biased Random-Key Genetic Algorithm to solve the defined problem; this is capable of obtaining high-quality feasible solutions over large numbers of instances in seconds. Moreover, we present insights derived from a case study into the locations of COVID-19 testing mobile laboratories in Nuevo Leon, Mexico. Our experimental results show that our optimization approach can be used as a diagnostic tool to determine the number of mobile labs needed to satisfy a set of demand centroids, assuming that users have reduced mobility due to the restrictions because of the pandemic.

Conscious Exploration of Alpha-Cuts in the Parametric Solution of the School Bus Routing Problem with Fuzzy Walking Distance.

Combinatorial optimization problems allow for modeling multiple situations in which proper allocation of resources is needed. For some real-world problems, the use of fuzzy elements in the models allows for incorporating certain levels of uncertainty to better approximate such real-world situations. One way to solve combinatorial optimization problems with fuzzy elements is the parametric approach, where it is necessary to define how to explore different relaxation levels using alpha-cuts. Researchers tend to select such alpha-cuts uniformly. The current investigation proposes a novel strategy for selecting alpha-cuts in the School Bus Routing Problem with fuzzy students' maximum walking distance. This proposal bases its foundations on the number of student-bus stop pairs available according to the different levels of relaxations allowed. Results demonstrate how the proposed strategy gives attractive solutions with more diverse trade-offs, contrasted with other methods in the literature. Furthermore, it decreases the computational cost for those instances where the maximum relaxation does not provide new pairs of students-bus stops.

A partial evaluation approach for the School Bus Routing Problem.

Several real-life optimization problems, such as the case of several instances of the School Bus Routing Problem (SBRP), are very complex and expensive to solve with exact algorithms. Metaheuristics are a good alternative in these situations because they are capable of generating good quality solutions to these problems in a reasonable time. Metaheuristics iterate thousands of times by introducing changes concerning the previous solutions. Each new solution must be evaluated, and sometimes, the new solutions have elements unchanged that are unnecessarily re-evaluated. However, an approach avoids repeatedly evaluating parts of different solutions known as partial evaluation. This work applies this technique to the SBRP to reduce its execution time. To apply the partial evaluation approach in this problem, each solution contains the information of the change that was made concerning the solution from which it originates. With this information, when evaluating the objective function, it will be only necessary to analyze the routes that changed. In the literature reviewed, no previous work was found in which the partial evaluation approach has been applied in the context of SBRP. In this paper we apply it in order to reduce the computational cost of SBRP solutions based on metaheuristics. The results show that it is possible to decrease the execution time in 80% of the instances, reducing the execution time on average by 73.6%.

Detection of DIAG and LINE Patterns in PassPoints Graphical Passwords Based on the Maximum Angles of Their Delaunay Triangles.

An alternative authentication method to traditional alphanumeric passwords is graphical password authentication, also known as graphical authentication, for which one of the most valuable cued-recall techniques is PassPoints. This technique stands out for its security and usability. However, it can be violated if the user follows a predefined pattern when selecting the five points in an image as their passwords, such as the DIAG and LINE patterns. Dictionary attacks can be built using these two patterns to compromise graphical passwords. So far, no reports have been found in the state of the art about any test capable of detecting graphical passwords with DIAG or LINE patterns in PassPoints. Studies carried out in other scenarios have shown the effectiveness of the characteristics of Delaunay triangulations in extracting information about the dependence between the points. In this work, graphical passwords formed by five randomly selected points on an image are compared with passwords whose points contain patterns of the DIAG or LINE type. The comparison is based on building for each password its Delaunay triangulation and calculating the mean value of the maximum angles of the triangles obtained; such a mean value is denoted by amadt. It is experimentally shown that in passwords containing DIAG and LINE patterns, the value of amadt is higher than the one obtained in passwords formed by random dots. From this result, it is proposed to use this amadt value as a statistic to build a test of means. This result constitutes the work's main contribution: The proposal of a spatial randomness test to detect weak graphic passwords that contain DIAG and LINE type patterns. The importance and novelty of this result become evident when two aspects are taken into account: First, these weak passwords can be exploited by attackers to improve the effectiveness of their attacks; second, there are no prior criteria to detect this type of weak password. The practical application of said test contributes to increasing PassPoints security without substantially affecting its efficiency.

Transfer Entropy Granger Causality between News Indices and Stock Markets in U.S. and Latin America during the COVID-19 Pandemic.

The relationship between three different groups of COVID-19 news series and stock market volatility for several Latin American countries and the U.S. are analyzed. To confirm the relationship between these series, a maximal overlap discrete wavelet transform (MODWT) was applied to determine the specific periods wherein each pair of series is significantly correlated. To determine if the news series cause Latin American stock markets' volatility, a one-sided Granger causality test based on transfer entropy (GC-TE) was applied. The results confirm that the U.S. and Latin American stock markets react differently to COVID-19 news. Some of the most statistically significant results were obtained from the reporting case index (RCI), A-COVID index, and uncertainty index, in that order, which are statistically significant for the majority of Latin American stock markets. Altogether, the results suggest these COVID-19 news indices could be used to forecast stock market volatility in the U.S. and Latin America.

Information Theory Based Evaluation of the RC4 Stream Cipher Outputs.

This paper presents a criterion, based on information theory, to measure the amount of average information provided by the sequences of outputs of the RC4 on the internal state. The test statistic used is the sum of the maximum plausible estimates of the entropies H(jt|zt), corresponding to the probability distributions P(jt|zt) of the sequences of random variables (jt)t∈T and (zt)t∈T, independent, but not identically distributed, where zt are the known values of the outputs, while jt is one of the unknown elements of the internal state of the RC4. It is experimentally demonstrated that the test statistic allows for determining the most vulnerable RC4 outputs, and it is proposed to be used as a vulnerability metric for each RC4 output sequence concerning the iterative probabilistic attack.

Selecting an Effective Entropy Estimator for Short Sequences of Bits and Bytes with Maximum Entropy.

Entropy makes it possible to measure the uncertainty about an information source from the distribution of its output symbols. It is known that the maximum Shannon's entropy of a discrete source of information is reached when its symbols follow a Uniform distribution. In cryptography, these sources have great applications since they allow for the highest security standards to be reached. In this work, the most effective estimator is selected to estimate entropy in short samples of bytes and bits with maximum entropy. For this, 18 estimators were compared. Results concerning the comparisons published in the literature between these estimators are discussed. The most suitable estimator is determined experimentally, based on its bias, the mean square error short samples of bytes and bits.

Measuring Independence between Statistical Randomness Tests by Mutual Information.

The analysis of independence between statistical randomness tests has had great attention in the literature recently. Dependency detection between statistical randomness tests allows one to discriminate statistical randomness tests that measure similar characteristics, and thus minimize the amount of statistical randomness tests that need to be used. In this work, a method for detecting statistical dependency by using mutual information is proposed. The main advantage of using mutual information is its ability to detect nonlinear correlations, which cannot be detected by the linear correlation coefficient used in previous work. This method analyzes the correlation between the battery tests of the National Institute of Standards and Technology, used as a standard in the evaluation of randomness. The results of the experiments show the existence of statistical dependencies between the tests that have not been previously detected.

Metaheuristics in the Optimization of Cryptographic Boolean Functions.

Generating Boolean Functions (BFs) with high nonlinearity is a complex task that is usually addresses through algebraic constructions. Metaheuristics have also been applied extensively to this task. However, metaheuristics have not been able to attain so good results as the algebraic techniques. This paper proposes a novel diversity-aware metaheuristic that is able to excel. This proposal includes the design of a novel cost function that combines several information from the Walsh Hadamard Transform (WHT) and a replacement strategy that promotes a gradual change from exploration to exploitation as well as the formation of clusters of solutions with the aim of allowing intensification steps at each iteration. The combination of a high entropy in the population and a lower entropy inside clusters allows a proper balance between exploration and exploitation. This is the first memetic algorithm that is able to generate 10-variable BFs of similar quality than algebraic methods. Experimental results and comparisons provide evidence of the high performance of the proposed optimization mechanism for the generation of high quality BFs.

Antibiotic-Resistant Septicemia in Pediatric Oncology Patients Associated with Post-Therapeutic Neutropenic Fever.

Death in cancer patients can be caused by the progression of tumors, their malignity, or other associated conditions such as sepsis, which is a multiphasic host response to a pathogen that can be significantly amplified by endogenous factors. Its incidence is continuously rising, which reflects the increasing number of sick patients at a higher risk of infection, especially those that are elderly, pediatric, or immunosuppressed. Sepsis appears to be directly associated with oncological treatment and fatal septic shock. Patients with a cancer diagnosis face a much higher risk of infections after being immunosuppressed by chemotherapy, radiotherapy, or anti-inflammatory therapy, especially caused by non-pathogenic, Gram-negative, and multidrug-resistant pathogens. There is a notorious difference between the incidence and mortality rates related to sepsis in pediatric oncologic patients between developed and developing countries: they are much higher in developing countries, where investment for diagnosis and treatment resources, infrastructure, medical specialists, cancer-related control programs, and post-therapeutic care is insufficient. This situation not only limits but also reduces the life expectancy of treated pediatric oncologic patients, and demands higher costs from the healthcare systems. Therefore, efforts must aim to limit the progression of sepsis conditions, applying the most recommended therapeutic regimens as soon as the initial risk factors are clinically evident-or even before they are, as when taking advantage of machine learning prediction systems to analyze data.

Real-time biofeedback device for gait rehabilitation of post-stroke patients.

In this work, we develop a device, called 'Walk-Even', that can provide real-time feedback to correct gait asymmetry commonly exhibited in post-stroke survivors and persons with certain neurological disorders. The device computes gait parameters, including gait time, swing time, and stance time of each leg, to detect gait asymmetry and provide corresponding real-time biofeedback by means of auditory and electrotactile stimulation to actively correct the user's gait. The system consists of customized force-sensor-embedded insoles adjustable to fit any shoe size, electrotactile and auditory feedback circuits, microcontroller, and wireless XBee transceivers. The device also offers data saving capability. To validate its accuracy and reliability, we compared the gait measurements from our device with a commercial gait and balance assessment device, Zeno Walkway. The results show good correlation and agreement in a validity study with six healthy subjects and reliability study with seventeen healthy subjects. In addition, preliminary testing on six post-stroke patients after an 8-week training shows that the Walk-Even device helps to improve gait symmetry, foot pressure and forefoot loading of the affected side. Thus, initial testing indicates that the device is accurate in measuring the gait parameters and effective in improving gait symmetry using real-time feedback. The device is portable and low cost and has the potential for use in a non-clinical setting for patients that can walk independently without assistance. A more extensive testing with stroke patients is still ongoing.

Intoxicación por paraquat: presentación de un caso y revisión de la literatura / Paraquat poisoning: case report and literature review

El Paraquat es un herbicida moderadamente peligroso clase II que se dirige fundamentalmente a los pulmones y genera allí radicales libres oxidantes; por eso, en los casos de intoxicación aguda está totalmente contraindicado usar oxigeno excepto cuando la PaO2 sea inferior a 50mm Hg. Dentro de los efectos locales se tiene a las ulceras bucales, pereforaciones esofágicas por lo corrosivo del herbicida, efectos sistémicos de falla renal, hepática y respiratoria, El tratamiento es en base lavado gástrico con carbón activado, tierra fuller y catárticos salinos. El uso temprano de antioxidantes corticoide y ciclofosfamida puede ser útil. Presentamos un caso de intoxicación aguda ´paraqual con fines suicidas, que llega a nuestro hospital 4 días de la ingesta con disfunción renal y hepática, desarrollando insuficiencia respiratoria, posterior fracaso multiorgánico con desenlace fatal. En estos casos es importante reconocer a tiempo la clinica, el tiempo transcurrrido desde la ingesta y la dosis, para que el ratamiento sea oportuno y adecuado.

Neumomediastino espontaneo: reporte de un caso y revisión de la fisiopatologia / Spontaneous pneumomediastinum: a case report and pathophysiology review

El Neumomediastino Espontaneo (NME) es una entidad poco frecuente que se manifiesta generallmente en personas jóvenes sin un factor o enfermedad predisponentes de forma evidente. Se lo cataloga como espontaneo al no encontrar relación con trauma y otros procesos previos identificables. La ruptura alveolar en el intersticio pulmonar es el mecanismo fisiopatológico responsable del escape y disección del gas hacia hilio, mediastino y otras regiones productos de un episodio agudo de alta presión torácica. Generalmente el NME esta causado por asma aguda severa, hiperreactividad bronquial inducido por tóxicos y barotrauma causado por maniobra de vaisalva, hiperreactividad bronquial inducido por tóxicos y barotrauma causado por maniobra de vaisalva. En este estudio se presenta un caso debido a un episodio de acceso de tos y probable hiperreactividad bronquial por infección viral aguda, y se discute la fisiopatología responsable de este proceso.

Sindrome de Parry Romberg a proposito de un caso / Parry Romberg syndrome on the subject of a case

El sindrome de Parry Romberg (RPR) o hemiatrofia facial progresiva es una efermedad rara, caracteriza por una atrofia unilateral de la piel, tejido subcuatáneo y las estructuras subyacentes óseas. Esta entidad es un proceso de etiologia desconocida que evoluciona con lesiones invalidantes que pueden estar asociadas con diferentes alteraciones neurológicas, cutaneas, oculares, enfermedades autoinmunes; hay algunos informes que muestran la asociación entre el Parry Romberg y la borrliosis traumas y el tratamiento quirúrgico. Se describe el caso en el servicio de diagnóstico por imágenes de una adolescente de 19 años con un cuadro clinico desde sus nueve años con signos clásicos de hemiotrofia facial sin antecedentes de importancia. al momento sin datos de complicaciones propias de esta enfermedad con presencia de defecto estético. Un diagnostico oportuno y temprano puede evitar aun más las deformidades faciales y un método de diagnostico adecuado es la TC MULTISLIDE.

Aplicación de plaguicidas en campo / Pesticide application in field

En la presente cartilla presenta recomendaciones y cuidados con el uso de los plaguicidas, ya que son sustancias tóxicas que pueden causar daños a la salud y al medio ambiente

Las medidas de seguridad en materia penal juvenil / Security measures in juvenile criminal law

En la actualidad exite una ardua discusión sobre las sanciones dentro del derecho penal juvenil, tema que cobra especial relevancia cuando nos enfrentamos a conductas delictivas cometidas por personas menores de edad en las cuales se ha determinado su condiciçon de inimputables o toxicómanos a partir de las conclusiones de las pericias respectivas. El cuestionamiento nos lleva a dos posibles soluciones: una darle un abordaje como un problema de salud y excluirlo del derecho penal y otra, mantener la línea tradicional, en la cual se faculta al derecho penal sancionar la conducta delictiva, imponiendo una medida de seguridad. Si se admite la primera posición, la normativa aplicable lo constituye el Código de la Niñez y la Adolescencia, el cual contempla la posibilidad de imponer medidas de protección para quienes están en una situación de vulnerabilidad, dentro de las que se ubican los casos de inimputables y toxicómanos, esto implica admitir medidas de "seguridad o protección" con una naturaleza jurídica de carácter administrativo. Posición que implicaría no sólo una vulneración de derechos sino que contraviene lo señalado por Sala Constitucional, la cual al desarrollar el alcance del artículo 39 de la Constitución Política, ha señalado que la imposición de las sanciones y por ende de las medidas de seguridad gozan de la garantía de la reserva de ley, destacando su naturaleza jurisdiccional y exclusivamente ante la comisión de delitos. La única solución posible en aras del respeto de esta reserva legal, es aplicar, conforme al artículo 9 de la Ley de Justicia Penal Juvenil la legislación penal de adultos y admitir la imposición de medidas de seguridad en la justicia penal juvenil.

Currently, there has been an arduous discussion about penalties in juvenile criminal law, topic which becomes especially relevant when we are faced to criminal conducts from people who are underage, in which their condition of not guilty or drug addict has been determined from the conclusions of respective expertise. The question leads up to two possible solutions: first, face it like a health problem and exclude it from criminal law; second, keep the traditional line, in which the criminal law can punish the criminal conduct, imposing a security measure. If we admit the first solution, the laws applicable are the Code of Childhood and Adolescence, contemplating the possibility of applying protection measures towards those who are in a vulnerable situation, in which we would put the cases of the not guilty and the drug addicts; this would imply admitting "security or protection" measures with a juridical nature of administrative sort. Position that would imply not only a weakening of rights, but would also violate what the Constitutional Chamber has said, when studying the scope of Article 39 of the Political Constitution, that the imposition of punishments and security measures have the guarantee of law reserve, which makes its nature jurisdictional and exclusive to when a crime is committed. The only possible solution, in order to respect this law reserve, is to apply, according to Article 9 of the Law of Juvenile Criminal Justice, the legislation applicable to adults and to admit the imposition of security measures in juvenile criminal justice.

Documento de sistematización del proyecto "PLAGBOL" 2001-2005 / Document of systematization of the \"PLAGBOL\" project 2001 - 2005

El presente documento persigue describir de una manera didáctica y comprensible las actividades y experiencias del proyecto Plaguicidas Bolivia, se divide en dos partes: la primera destinada a mostrar la organización del proyecto y las instituciones participantes como ejecutoras, describiendo la conformación del mismo y el rol de cada una de ellas; la segunda parte describe las fases desarrolladas por el proyecto, desde el proceso de adquisición de bienes y contratación del personal