Violencia criminal y desplazamiento en México

La descontrolada violencia criminal empuja de distintas formas a la gente a trasladarse a otros lugares, desde la coacción directa y las amenazas físicas a la erosión de la calidad de vida y las oportunidades laborales. No todas las personas que se desplazan forzadamente tienen el mismo acceso a la protección o el asilo

LOCAL SITE SEISMIC RESPONSE IN AN INTER-ANDEAN VALLEY: GEOTECHNICAL CHARACTERIZATION AND SEISMIC AMPLIFICATION ZONATION OF THE SOUTHERN QUITO AREA

Over the last century, earthquakes have claimed the lives of thousands of people and caused considerable damage to existing buildings in several places in South America. According to Chunga et al (2018), in Ecuador, there are records since 1906 showing significant events with magnitudes between Mw 7.1 and Mw 8.8. However, the population has not been aware of the potential effects of an earthquake of these magnitudes, causing considerable seismic vulnerability due to unstudied and low-cost informal constructions. For this reason, the necessity to analyze the local seismic response of the South Quito area arises, evaluating the seismic amplification considering the lithostratigraphic and geomorphological characteristics of the inter-Andean area. To achieve this, 20 boreholes of 30 m depth distributed in this area were complemented with a campaign of 1332 field tests and 2774 laboratory tests. The information obtained from the campaign was used to form 9 zones consisting of one or a group of boreholes according to their geographic location, physical and mechanical characteristics, generating a soil column for each zone. Three types of analysis were carried out to define the soil dynamic parameters: with theoretical values, with parameters derived from dry and remolded samples, performing a total of 46 resonant column tests. The results showed that, for the 9 defined zones in southern Quito, the amplification factors ranged between 3.07 and 7.74, which helps us to evaluate the vulnerability of this area of the city, by zoning and risk mapping. Nevertheless, the need for further investigation of the subsoil is emphasized, in addition to the analysis of amplification factors based on the earthquakes in this sector.Nell'ultimo secolo, i terremoti hanno provocato la morte di migliaia di persone e causato notevoli danni agli edifici esistenti in diverse località del Sud America. Secondo Chunga et al (2018), in Ecuador esistono registrazioni dal 1906 che mostrano eventi significativi con magnitudo tra Mw 7.1 e Mw 8.8. Tuttavia, la popolazione non era a conoscenza dei potenziali effetti di un terremoto di queste magnitudo, causando una notevole vulnerabilità sismica a causa di costruzioni informali non studiate ea basso costo. Nasce pertanto la necessità di analizzare la risposta sismica locale dell'area sud di Quito, valutandone l'amplificazione sismica considerando le caratteristiche litostratigrafiche e geomorfologiche dell'area interandina. Per raggiungere questo obiettivo, 20 sondaggi di 30 m di profondità distribuiti in quest'area sono stati integrati con una campagna di 1332 prove in campo e 2774 prove in laboratorio. Le informazioni ottenute dalla campagna sono state utilizzate per formare 9 zone costituite da uno o da un gruppo di sondaggi in base alla loro posizione geografica, caratteristiche fisiche e meccaniche, generando una colonna di suolo per ciascuna zona. Sono state effettuate tre tipologie di analisi per definire i parametri dinamici del suolo: con valori teorici, con parametri derivati da campioni secchi e rimodellati, eseguendo un totale di 46 prove su colonna risonante. I risultati hanno mostrato che, per le 9 zone definite nel sud di Quito, i fattori di amplificazione erano compresi tra 3,07 e 7,74, il che ci aiuta a valutare la vulnerabilità di quest'area della città, mediante la zonizzazione e la mappatura del rischio. Tuttavia, viene sottolineata la necessità di ulteriori indagini del sottosuolo, oltre all'analisi dei fattori di amplificazione basati sui terremoti in questo settore

La autorización del Procurador General del Estado para el sometimiento a arbitraje nacional en los contratos estatales

This paper refers to the need for the authorization of the Attorney General of the State to submit to arbitration disputes national public contracts. In this regard, doctrine and jurisprudence to support it are reviewed. The thesis concludes that the authorization of the Attorney General under Article 190 is indicated prior and compulsory in government procurement.El presente trabajo se refiere a la necesidad de contar con la autorización del Procurador General del Estado para someter a arbitraje nacional controversias en contratos públicos. Al respecto se revisó doctrina y jurisprudencia para sustentarlo. La tesina concluye que la autorización del Procurador General conforme al señalado artículo 190 es previa y obligatoria en contratación pública

A SEDIMENTOLOGIC, SEQUENCE STRATIGRAPHIC, AND ICHNOLOGIC CHARACTERIZATION OF THE CRETACEOUS U AND M2 SANDSTONE MEMBERS, NAPO FORMATION, ORIENTE BASIN OF ECUADOR

The Upper Cretaceous M2 and U Sandstone members of the Napo Formation are prolific hydrocarbon producers in the Oriente Basin, Ecuador. To understand the depositional origin of these reservoirs, a detailed sedimentologic, sequence-stratigraphic, and ichnologic study was performed, using 490 ft (ca. 149 m) of conventional core from six wells. Sedimentary facies, stratal stacking pattern, discontinuity surfaces, and trace fossils were documented. Nine lithofacies, two depositional sequences in each member, and depauperate and fully marine ichnofacies were identified. Both members present evidence of tidal (e.g. mudstone drapes on bedforms, double mudstone layers, flaser, wavy, and lenticular bedding, and thick-and- thin alternations of siltstone and claystone layers) and river (e.g. hyperpycnal flow deposits) influence. The shoreline was trending northeast-southwest within the study area and the predominant sediment source came from cratonic areas located to the east. In the study area, the U Sandstone Member represents three main broad environments: fluvial, estuarine, and deltaic. The base of the U Sandstone Member marks the base of depositional sequence 1 (DSU1), representing a subaerial unconformity formed as a result of valley incision during a relative fall of sea level. DSU1 comprises the lower and middle intervals and the lower part of the upper interval. DSU1 consists of lowstand moderate-sinuosity fluvial deposits, followed by transgressive estuarine deposits and highstand mixed tide- and river-influenced deltaic deposits. A subaerial unconformity marks the base of depositional sequence 2 (DSU2), which was followed by renewed lowstand fluvial deposition within an incised valley in the more proximal areas and transgressive estuarine sedimentation. DSU2 is recorded in the upper part of the upper interval. Trace fossils in the U Sandstone Member are recorded in the estuarine and deltaic deposits; fluvial deposits present sparse bioturbation. The depauperate Skolithos and Cruziana ichnofacies are commonly present in the estuarine and deltaic deposits, recording brackish-water conditions. The M2 Sandstone Member records sedimentation in a mixed tide- and river-influenced deltaic environment, encompassing delta front and prodeltaic subenvironments, as well as transgressive deposits signaling deltaic abandonment. Two depositional sequences have been recognized (DSM1 and DSM2). The underlying A Limestone Member, which pinches out towards the east, most likely represents the transgressive systems tract (TST) of DSM1. Deposition may have been controlled by an interplay of eustatic changes, tectonism, and active volcanism. This member consists of discrete thickening- and coarsening-upward packages that may represent either parasequences or intervals recording delta lobe switching. The parasequence sets exhibit progradational-stacking (seaward) patterns and have clinoformal geometry that exhibit both vertical and lateral facies changes. Various degrees of biogenic reworking are recorded (BI 1-6), commonly in the sandstone-dominated facies, generally representing the depauperate Cruziana Ichnofacies, indicative of brackish-water conditions. Integration of ichnology, sequence stratigraphy, and sedimentology was fundamental in order to provide detailed paleoenvironmental models for the U and M2 Sandstone members. This study represents the first detailed ichnologic study in Ecuador. It is expected that this research will encourage geoscientists in the country to adopt these conceptual and methodological tools in reservoir characterization

Renditions of the “bogeywoman” myth in picturebooks Gloria Anzaldúa and Julia Alvarez

Traditionally, the Mexican myth of La Llorona and the Dominican ciguapa legend correspond to misogynist stereotypes; at the same time, there are versions of the folktales rooted in Azteca and Taíno cultures, combined with the influence and consequences of colonialism. In essence, La Llorona stands for a bad mother who drowned her children out of jealousy, and ciguapas, usually portrayed as beautiful creatures with backward-facing feet, embody the femme fatale as they entice and kill men. Moreover, both figures work as cautionary tales as they are often employed as bogeyman figures to scare children into obeying adults. Gloria Anzaldúa and Julia Alvarez challenge the patriarchal, colonialist and adultist versions, rewriting the myths through picturebooks that encourage agency, change, healing and love. In Anzaldúa’s “Prietita and the Ghost Woman”, settled at the US-Mexico border, La Llorona, instead of hurting children, guides the girl to find a plant to heal her mother’s illness, while in Alvarez’s “The Secret Footprints”, the ciguapas’ tribe do not prey on humans but hide in caves underwater; when the young protagonist Guapa goes to the surface, she befriends a human boy, instead of hurting him. I argue that both narratives construct a new rendition of the bogeywoman myth through the transformation of these figures into kind spirits thanks to an intersectional feminist, decolonial and child-centered approach

ENHANCING BALLISTIC IMPACT RESISTANCE OF POLYMER MATRIX COMPOSITE ARMORS BY ADDITION OF MICRO AND NANO-FILLERS

Improving the ballistic impact resistance of hybrid polymer matrix composites through addition of micro- and nano-particles as fillers is the principal goal of this research. Development of light-weight ballistic plates, made of polymer matrix composites with improved ballistic resistance, can offer a solution of shielding with lighter, thinner, stronger and less expensive materials than the conventional ballistic plates. The use of micro- and nano-particles in low concentrations can achieve this goal without compromising the density or strength of the new armor plates. Firstly, laminated hybrid composites consisting of aluminum alloy plates, epoxy resin and Kevlar® fabrics were developed. Shear thickening fluid (STF) made of nano-particles of colloidal silica (SiO2) was impregnated into Kevlar® fabrics to determine its effect on the energy absorption behavior of the composites. STF decreased the tendency of Kevlar® fibers to rupture during projectile penetration, and thus, increased its impact energy absorption performance when compared to the samples made of Kevlar® neat fabrics (containing no STF). Similar laminated hybrid composites were subsequently built through impregnation of micro- and nano-particles of aluminum, gamma alumina, silicon carbide, colloidal silica and potato flour into Kevlar fabrics by mixing these particles with polyethylene glycol. The obtained laminates were evaluated to determine their impact resistance and energy absorption capabilities under ballistic impact. The plates containing aluminum and colloidal silica nano-powders have the highest energy absorption capability of between 679 up to 693 J for plate thickness and areal density of about 10.8 mm and 1.9 g/cm2, respectively. These laminates can meet the protective requirements for levels IIA, II, and IIIA to resist ballistic impact from pistols caliber 9 mm. In another approach, hybrid composite armor plates based on high density polyethylene (HDPE) were prepared by using 10 wt.% of Kevlar® short fibers, and 20 wt.% chonta palm wood, potato flour, colloidal silica or gamma alumina particles. Addition of colloidal silica and gamma alumina nano-particles improve stiffness by 43.5% and increase impact energy absorption capability by 20%, compared to control sample, which is HDPE containing 10 wt.% Kevlar® short fibers. Hybrid bio-composites made of 10 wt.% Kevlar® short fibers and varying amount of chonta wood particles (10, 20, 30 wt. %), as additional reinforcement, were also developed and investigated. The hybrid composite plates containing 10 wt.% chonta palm wood micro-particles exhibited the highest energy absorption capability of 62.4 J, which is equivalent to 19.5 % improvement over control specimens: HDPE reinforced with 10 wt.% Kevlar® short fibers. Finally, bio-composites made of HDPE reinforced with varying fractions of micro-particles of chonta palm wood (10, 20, 25, and 30 wt. %) were developed and characterized. The ballistic impact performance of the biocomposites containing 25 wt.% chonta palm wood particles exhibited the highest energy absorption of 53.4 J, which represents a 41.3% improvement over the unreinforced HDPE specimens with similar thickness and density

Aportes de una secuencia didáctica mediada por las tecnologías de la información y la comunicación-TIC- al desarrollo de la habilidad del pensamiento crítico evaluación de la información en los estudiantes de grado noveno de la Institución Educativa Leningrado Cuba

El presenta trabajo de investigación consiste en la aplicación de una secuencia de aprendizaje colaborativo para el desarrollo y la transformación del pensamiento crítico, fundamentalmente en la competencia evaluación de la información, mediada por TIC. Es una investigación de tipo cuantitativa que busca evidenciar a partir de procesos estadísticos que el problema del No desarrollo de esta competencia fundamental en el paradigma actual radica en las didácticas a emplear, utilizando en la secuencia un pre-test y un post-test para la recolección de los datos, la secuencia didáctica fue basada en los modelos de Zabala, con un corpus teórico desde autores como López Aymes Gabriela y el proyecto Delphi con respecto al pensamiento crítico, y los postulados de Cesar Coll acerca de entender las TIC como una nueva cultura del aprendizaje

English Majors’ Perceptions on Factors Influencing the Development of their Oral Fluency

Existen varias consideraciones acerca del desarrollo de fluidez en la destreza oral del idioma inglés que involucran a la comunicación desde una perspectiva bilingüe, las cuales requieren de un análisis profundo en el campo de la enseñanza-aprendizaje del inglés como una lengua extranjera en Ecuador. Este trabajo determinará los factores que tienen influencia en el desarrollo de la destreza oral y la fluidez de los estudiantes de la Carrera de Inglés, quienes están en un nivel intermedio en la Universidad Técnica del Norte. Para este estudio se aplicó un enfoque cuantitativo orientado a identificar y medir los factores que tienen influencia en el desarrollo de la destreza oral del idioma inglés, y con ello entender los aspectos positivos y negativos y su influencia durante el proceso de comunicación en la lengua objeto de estudio. A fin de determinar y categorizar los factores, se aplicó la investigación descriptiva con un método inductivo. Para el efecto, estudiantes de 5to nivel de la carrera de Inglés fueron encuestados. Los resultados evidenciaron factores con influencia tales como la exposición al idioma inglés fomentado principalmente por los profesores, y el rol de la interacción dentro y fuera de las aulas. Finalmente, este estudio deja una nueva interrogante abierta acerca de la fluidez oral para realizar futuras investigaciones.There are several implications about oral fluency development of the English language that involve communication from a bilingual perspective, which require a further analysis in the field of teaching-learning English as a foreign language in Ecuador. This research project will determine the factors that influence the development of the oral skill and fluency in undergraduate English major students who are in an intermediate level, at Universidad Técnica del Norte. At this aim, a quantitative approach was applied to identify and measure the factors influencing the oral skill development of the English language, and with this to understand positive and negative aspects that influence fluency during the communication process in the target language. In determining and categorizing factors, a descriptive research along with an inductive method were also applied. To this effect, 5th level English majors were surveyed. The results identified influential factors such as the language exposure mainly fostered by teachers, and the role of interaction inside and outside of the classroom. Finally, this study leaves a new question about oral fluency open for a further research work

Micro gerencia de la cadena de suministro análisis en las decisiones de micro y pequeña empresa del sector textil en Pichincha- Ecuador

The micro and small-sized enterprises represent more than the 80% of the sources of employment in Latin America, as well as more than the 50% of a country's GDP, according to global estimates. Due to the importance of these latter and the lack of research in micro and small enterprises in Ecuador, the desire to carry out this study with a focus on the textile sector of the province of Pichincha has been generated. This work consists of analyzing the level of adoption of supply chain practices and the decision making of managers in different areas of the company. To achieve this, the DMAIC six sigma methodology is used, completing until the Analyze phase. The information is raised following five steps proposed by the MIT Scale, which are part of a study of productivity improvement in Latin America. These steps involve the use of a questionnaire, company tour, immersion process, shadowing the person who makes the decisions and finally the debrief to this person. Once the companies are analyzed, it is observed that most of the activities that the managers perform are focused on the logistics, operations, and supply chain of the company. These activities are mostly carried out on the person's own initiative without being planned, or activities on the list of duties without a set timetable and each indicator is usually accomplished below 75%. In addition, recommendations are made for each of the steps proposed by MIT Scale based on experience in executing this project.La micro y pequeña empresa representa más del 80% de las fuentes de trabajo en América Latina, así como también más del 50% del PIB de un país, de acuerdo a estimaciones mundiales. Debido a la importancia de estas y a la falta de investigación en micro y pequeñas empresas en el Ecuador, se ha generado el deseo de realizar este estudio con un enfoque hacia el sector textil de la provincia de Pichincha. Este trabajo consiste en el análisis del nivel de adopción de prácticas de la cadena de suministro y la toma de decisiones de los gerentes en diferentes áreas de la empresa. Para lograr esto, se utiliza la metodología six sigma de DMAIC, completando hasta la fase Analizar. La información se levanta siguiendo cinco pasos propuestos por el MIT Scale, los cuales son parte de un estudio de mejoramiento de la productividad a nivel de Latinoamérica. Estos pasos involucran el uso de un cuestionario, visita a la compañía, proceso de inmersión, seguimiento a la persona que toma las decisiones y finalmente el debrief a esta persona. Una vez analizadas las empresas, se observa que la mayor parte de las actividades que realizan los gerentes son enfocadas a la logística, operaciones y cadena de suministro de la empresa. Dichas actividades son ejecutadas, en su mayoría, por iniciativa propia de la persona sin ser planificadas, o actividades en lista de deberes sin un horario establecido y cada indicador por lo general se cumple por debajo del 75%. Adicionalmente, se realizan recomendaciones para cada uno de los pasos propuestos por el MIT Scale basados en la experiencia al ejecutar este proyecto