Modelo dinámico-probabilístico sobre el comportamiento de los pueblos indígenas en aislamiento de la Amazonia Ecuatoriana.

La supervivencia de los pueblos en aislamiento (PIAs), Tagaeri? Taromenane en la Amazonia ecuatoriana, está influida por agentes externos y características culturales. El área definida como Zona Intangible para el desplazamiento de los PIAs presenta cierta debilidad geográfica, lo que alterna el funcionamiento de estas comunidades. El objetivo de este trabajo es conocer el comportamiento de las comunidades aisladas en relación con las fronteras de contactos. Se ha utilizado el software libre NetLogo versión 5.0.3, para simular la evolución durante 100 años de dos comunidades. Las poblaciones estimadas iniciales de indígenas en asilamiento fue de 100, 500, 1000 individuos por escenario. El comportamiento está condicionado por las variables: individuos Taromenane, individuos Tagaeri, tasa de nacimientos, disponibilidad de alimento en la Amazonía, crecimiento de la vegetación, valor energético de la alimentación, y energía de la vegetación. Las características guerreras por la protección de territorio propias de los PIAs, han permitido concluir que la intensificación de las presiones externas sumadas a los enfrenamientos entre grupos aislados genera su propia extinción en un espacio temporal de 100 años

Reduced abrasion drilling fluid

A reduced abrasion drilling fluid system and method of drilling a borehole by circulating the reduced abrasion drilling fluid through the borehole is disclosed. The reduced abrasion drilling fluid comprises a drilling fluid, a first additive and a weighting agent, wherein the weighting agent has a particle size of at least 90% by volume less than 50 um

Hydrocarbon formation core protection and and transportation apparatus

An apparatus for transporting core samples includes an outer tube having an open end and a cover removably mounted to the open end; a core tube slidable into and out ofthe outer tube when the cover is removed from the outer tube; and a stabilizing structure between the core tube and the outer tube, the stabilizing structure supporting the core tube within the outer tube with the core tube spaced from contact with an inner wall ofthe outer tube

La cultura escolar y sus incidencia en el abandono escolar en la instituci?n educativa Julio Ernesto Andrade

155 p. Recurso Electr?nicoEl abandono escolar es un fen?meno agudo multicausal que en las zonas rurales influye en la pobreza y desigualdad de la poblaci?n. En el estudio se evade el concepto ?deserci?n? significado que culpabiliza exclusivamente al estudiante y se usa ?abandono escolar? que tiene en cuenta el papel de las I.E. en la exclusi?n de los estudiantes. Para ello se analiza la cultura escolar como principal factor intra - escolar del abandono escolar a trav?s de tres categor?as de an?lisis: pr?cticas de ense?anza docente, relaci?n docente - estudiante y creencias acerca del abandono escolar. El estudio analiza la tasa intra ? anual de abandono escolar en los niveles de educaci?n b?sica secundaria y media en la IE Julio Ernesto Andrade ubicada en la vereda ?La Selva? del municipio de Rovira (Tolima). La metodolog?a es principalmente de enfoque cualitativo con un dise?o etnogr?fico y como t?cnica la entrevista semiestructurada a docentes, desertores y estudiantes que permite un an?lisis profundo a trav?s de la triangulaci?n de sus respuestas. Como resultado se encontr? incoherencias en el PEI que influyen en las malas pr?cticas de ense?anza y afectan la relaci?n docente ? estudiante. Esto lleva a la indisciplina, el bajo desempe?o escolar y la reprobaci?n que finaliza en el abandono escolar de los estudiantes por iniciativa propia o por presi?n de sus acudientes. Palabras clave: cultura escolar, abandono escolar, deserci?n escolar, pr?cticas de ense?anza, relaci?n docente ? estudiante.School dropout is an acute multi-causal phenomenon that in rural areas influences poverty and inequality of the population. In the study, the concept of "desertion" was evaded, meaning that the student is blamed exclusively and "school dropout" is used, which takes into account the role of the School Institutions in the exclusion of students. To this end, the school culture is analyzed as the main intra - school factor of school dropout through three categories of analysis: teaching practices, teacher - student relationship and beliefs about school dropout. The study analyzes the intra - annual drop - out rate at the secondary and middle school levels at the Julio Ernesto Andrade School located in the village "La Selva" in the municipality of Rovira (Tolima). The methodology is mainly of a qualitative approach with an ethnographic design and as a technique the semi-structured interview with teachers, dropouts and students that allows a deep analysis through the triangulation of their answers. As a result, inconsistencies were found in the Institutional Educational Plan that influence bad teaching practices and affect the teacher-student relationship. This leads to indiscipline, poor school performance and failure that ends in dropping out of students on their own initiative or due to pressure from their parents. Keywords: school culture, school dropout, teaching practices, teacher-student relationship

Sol-gel synthesis and multiferroic properties of pyrochlore-free Pb(Fe0.5Nb0.5)O3 thin films

Lead iron niobate (PbFe0.5Nb0.5O3 - PFN) thin films were synthesized by a modified sol-gel route, which offers the advantage of a rapid, simple and non-toxic reaction method. Polycrystalline perovskite-structured PFN thin films without pyrochlore phases were obtained on Pt/Ti/SiO2/Si substrates after sintering by rapid thermal annealing at 650 {\deg}C. TEM and AFM images confirmed the excellent quality of the sintered film, while EDS spectroscopy revealed the presence of oxygen vacancies near the film/substrate interface. Electric measurements show good dielectric properties and ferroelectric behavior, characterized by typical C-V curves and well-defined P-E ferroelectric loops at 1 kHz, with remanent polarization values of ~12 uC/cm2. The polarization, however, increases with decreasing frequency, indicating the presence of leakage currents. I-V measurements show a significant increase in DC-conduction at relatively low fields (around 100 kV/cm). The films display ferromagnetic behavior at room temperature, with magnetic remanence around 30 emu/cm3 and a coercive field of 1 kOe. These values are significantly higher than those obtained for PFN powders fabricated by the same sol-gel route, as well as the magnetization values reported in the literature for epitaxial films.Comment: 24 pages, 10 figure

Particle Swarm Optimization for Optimal Frequency Response with High Penetration of Photovoltaic and Wind Generation

As the installation of solar-photovoltaic and wind-generation systems continue to grow, the location must be strategically selected to maintain a reliable grid. However, such strategies are commonly subject to system adequacy constraints, while system security constraints (e.g., frequency stability, voltage limits) are vaguely explored. This may lead to inaccuracies in the optimal placement of the renewables, and thus maximum benefits may not be achieved. In this context, this paper proposes an optimization-based mathematical framework to design a robust distributed generation system, able to keep system stability in a desired range under system perturbance. The optimum placement of wind and solar renewable energies that minimizes the impact on system stability in terms of the standard frequency deviation is obtained through particle swarm optimization, which is developed in Python and executed in PowerFactory-DIgSILENT. The results reveal that the proposed approach has the potential to reduce the influence of disturbances, enhancing critical clearance time before frequency collapse and supporting secure power system operation

CARACTERIZACIÓN Y ACTIVIDAD ANTIOXIDANTE DEL ACEITE DE LA SEMILLA DE PALTA Persea americana MILL.

Avocado seed is a part of the fruit discarded in industrial pulp oil extraction and would be a source of essential fatty acids and other phytoconstituents. This research aimed to characterize oil seed Persea americana Mill. Var. Hass and Fuerte and its antioxidant activity. To oil obtained by the Soxhlet method, was made the physicochemical characterization following the AOCS (American Society of Chemical Oil) standards, the fatty acid profile by gas chromatographic method and the antioxidant activity by the DPPH method. Physicochemical characterization reported mean values and standard deviation of 2,12±0,015; 1,40±0,047; 242,30±5,449; 70,62±2,82 and 0,919±0,024 to acidity index, peroxide, saponification, iodine and specific gravity, respectively; with significance p <0,05. Were identified two essential fatty acids: linoleic acid (48,77%) and linolenic acid (12,17%), omega-6 and omega-3, respectively. Finally, the antioxidant activity expressed in μmol TE/kg, tuvo valores de 9,676±0,260; 8,700±0,260 and 7,37±0,169 for total oil, saponifiable and unsaponifiable fraction, respectively. Characterized oil had a quality comparable to the extra virgin olive oil and its antioxidant activity would due to the presence of polyphenols and steroids.La semilla de palta es una parte del fruto descartada en la obtención industrial del aceite de pulpa y podría ser una fuente de ácidos grasos esenciales y otros fitoconstituyentes. El presente trabajo de investigación tuvo como objetivo caracterizar al aceite de la semilla de Persea americana Mill. Var. Hass Fuerte y su actividad antioxidante. Al aceite obtenido por el método de Soxhlet, se le hizo la caracterización fisicoquímica siguiendo las normas AOCS (Sociedad Americana de la Química del Aceite), el perfil de ácidos grasos mediante el método cromatográfico de gases y la actividad antioxidante por el método DPPH. La caracterización fisicoquímica reportó valores promedios y desviación estándar de 2,12±0,015; 1,40±0,047; 242,30±5,449; 70,62±2,82 y 0,919±0,024 para índices de acidez, peróxido, saponificación, iodo y gravedad específica, respectivamente; con una significación p<0,05. Se identificaron dos ácidos grasos esenciales: ácido linoleico (48,77%) y ácido linolénico (12,17%), omega-6 y omega-3, respectivamente. Finalmente, la actividad antioxidante expresada en μmol TE/kg, tuvo valores de 9,676±0,260; 8,700±0,260 y 7,37±0,169 para el aceite total, la fracción saponificable y la insaponificable, respectivamente. El aceite caracterizado tuvo una calidad comparable al aceite de oliva extra virgen y su actividad antioxidante se debería a la presencia de polifenoles y esteroides

Social Licence to Operate e settore petrolifero nell\u2019Amazzonia ecuadoriana: un approccio geografico

Gli obiettivi di sostenibilit\ue0 al 2030 del settore del oil & gas indicano come prioritario l\u2019impegno delle compagnie petrolifere nella promozione dello sviluppo sostenibile delle comunit\ue0 presenti nei territori in cui esse operano. In questo modo l\u2019impresa pu\uf2 raggiungere pi\uf9 facilmente la cosiddetta Social Licence to Operate (SLO), ovvero il livello di accettazione delle attivit\ue0 di un\u2019impresa da parte delle comunit\ue0 locali. L\u2019obiettivo di questa ricerca, \ue8 sviluppare e testare un modello per misurare il livello di SLO di una compagnia petrolifera, analizzando in modo critico l\u2019applicazione di questo strumento nell\u2019Amazzonia ecuadoriana. L\u2019area di studio \ue8 il Blocco 10, gestito dalla compagnia petrolifera italiana Agip Oil Ecuador, filiale di Eni. Si tratta di un importante hotspot di biodiversit\ue0 popolato da diverse etnie indigene. La ricerca impiega un approccio geografico abbinato a metodi quali-quantitativi per esaminare le percezioni dei locali in merito agli impatti socio-ambientali delle operazioni dell\u2019impresa, elementi chiave nella definizione della SLO in un territorio. L\u2019assenza di informazioni geografiche precise dell\u2019area di studio \ue8 stata compensata mediante strumenti di Participatory GIS coinvolgendo le comunit\ue0 locali. Infine, l\u2019analisi GIS dei risultati sulle percezioni delle popolazioni permetter\ue0 di comprendere meglio le relazioni spaziali dei conflitti socio-ambientali e degli elementi critici della SLO nel territorio studiato

A longitudinal study of household water, sanitation, and hygiene characteristics and environmental enteropathy markers in children less than 24 months in Iquitos, Peru

Funding Information: Financial support: The MAL-ED is carried out as a collaborative project supported by the Bill & Melinda Gates Foundation, the Foundation for the National Institutes of Health, and the National Institutes of Health, Fogarty International Center. While conducting this work, Natalie Exum was supported by The NSF IGERT Grant 1069213, The Osprey Foundation of Maryland Grant 1602030014, the Johns Hopkins Water Institute, Johns Hopkins Fisher Center Discovery Program Grant 010 KOS2015, The Kazuyoshi Kawata fund in Sanitary Engineering and Science, and the Dr. C. W. Kruse Memorial Fund Scholarship. Publisher Copyright: © 2018 by The American Society of Tropical Medicine and Hygiene.Peer reviewedPublisher PD

Identification of Nontuberculous Mycobacteria in Drinking Water in Cali, Colombia

Nontuberculous mycobacteria (NTM) are ubiquitous microorganisms naturally resistant to antibiotics and disinfectants that can colonize drinking water supply systems. Information regarding the spread of NTM in specifically South America and Colombia is limited. We aimed to identify and characterize NTM present in tap water samples from Cali, Colombia. Drinking water samples and faucet biofilm swabs were collected in 18 places, including the city’s three main water treatment plants (WTPs). Filter-trapped material and eluates (0.45 μm) from swab washes were plated in 7H11 agar plates. Suspected colonies were evaluated microscopically, and NTM species were identified based on the rpoB gene. Antibiotic susceptibility testing was also performed. Fifty percent (9/18) of sampling points were positive for NTM (including two WTPs), from which 16 different isolates were identified: Mycobacterium mucogenicum (8/16), M. phocaicum (3/16), M. chelonae (2/16), M. mageritense (2/16), and M. fortuitum (1/16), all rapidly growing mycobacteria. A susceptibility profile was obtained from 68.75% (11/16) of the isolates. M. chelonae was the most resistant species. All NTM isolated are potentially responsible for human diseases; our findings might provide a baseline for exploring NTM transmission dynamics and clinical characterization, as well as potential associations between NTM species found in drinking water and isolates from patients