AMI en Latinoamérica Aproximación, análisis y propuesta de medición sobre el contexto de la Alfabetización Mediática e Informacional en América Latina

Esta tesis doctoral desarrolla una metodología para la evaluación de la alfabetización mediática e informacional (AMI), que se basa en los marcos propuestos por la UNESCO (2011, 2013) y la Comisión Europea (Celot y Pérez Tornero, 2009), brindando una adaptación de las recomendaciones diseñadas por estos dos grandes representantes de la AMI aplicable al contexto específico de América Latina. También hace una revisión de literatura sobre las teorías generales relacionadas con la alfabetización mediática e informacional, así como de estudios en AMI llevados a cabo en diferentes países, principalmente en los once seleccionados para esta investigación. De esta manera, se plantea un enfoque amplio sobre la AMI que tiene en cuenta diversos autores e instituciones que trabajan en este campo (ACRL, 2000; Ainley et al., 2012; NAP-ICTL, 2012; Pérez-Tornero, 2007; UNESCO, 2008; Celot y Pérez-Tornero 2009; Lau y Cortés, 2009; Renee Hobbs, 2010; UNESCO, 2011, 2013; Giraldo et al., 2014, entre otros). Teorías relacionadas con la edu-comunicación, la alfabetización mediática, estudios de medios, alfabetización informacional, alfabetización TIC/digital, alfabetizaciones múltiples, etc., han sido comparadas y analizadas. El resultado es la creación de un marco teórico sólido tanto sobre la competencia mediática como sobre la evaluación del contexto AMI. El estudio se basa en un profundo análisis de contenidos que sistematiza variables relacionadas con políticas públicas, planes de estudios, planes nacionales en TIC, seguridad cibernética y elementos relacionados con la AMI en general (alfabetización informacional, alfabetización digital, competencia mediática) en los once países estudiados. También tiene en cuenta un amplio cuestionario aplicado a una muestra de 44 expertos en AMI provenientes de Argentina, Chile, Colombia, Costa Rica, Ecuador, México, Panamá, Perú, República Dominicana, Uruguay y Venezuela. La investigación muestra cómo los países de América Latina se están adaptando a la sociedad del conocimiento -a velocidades bastante diferentes- y describe (y se centra en ello) un escenario de rápido movimiento en el que se observa la manera en que algunos países de la región comienzan a concentrar sus esfuerzos en acciones que van más allá de la fase embrionaria de generación de oportunidades de acceso a las TIC (infraestructura TI en general, programas 1:1, ciber-centros, construcción de redes, etc.). También muestra cómo los países del mismo nivel de ingresos (medio-alto) han llevado a cabo diferentes estrategias digitales que, en algunos casos, han conducido a resultados de alto impacto. El resultado de esta investigación es una propuesta de "Índice de preparación AMI" y un amplio primer mapeo de los factores que favorecen a la AMI en la región.This thesis develops an assessment methodology on Media and Information Literacy (MIL), which is based on the frameworks proposed by UNESCO (2011, 2013) and the European Commission (Celot & Pérez Tornero, 2009), adapting the directions given by these two major representatives in the field of MIL to the specific context of Latin America. It also makes a literature review on media and information literacy general theories as well as on MIL studies carried out in different countries, mainly in the eleven selected for this research. A broad approach to MIL is drafted taking into account several authors and institutions working on this field (ACRL, 2000; Ainley et al., 2012; NAP-ICTL, 2012; Pérez-Tornero, 2007; UNESCO, 2008; Celot & Pérez-Tornero, 2009; Lau & Cortés, 2009; Renee Hobbs, 2010; UNESCO, 2011, 2013; Giraldo et al., 2014, among others). Theories related to edu-communication, media literacy, media studies, information literacy, digital/ICT literacy, multiple literacies, etc. have been compared and analyzed. The result is the creation of a robust theoretical framework both on media competence and on MIL context assessment. The study relies on a deep content analysis that systematizes variables related to public policy, school curriculum, ICT plans, cyber-security, and media and information literacy elements (informational literacy, digital literacy, media competence) in the eleven countries studied. It also takes into account a comprehensive questionnaire with a sample of 44 MIL experts from Argentina, Chile, Colombia, Costa Rica, Ecuador, Mexico, Panama, Peru, Dominican Republic, Uruguay and Venezuela. The research shows how countries in Latin America are adapting to the Knowledge Society -at very different speeds- and describes (and focuses on) a fast-moving scenario where some countries of the region are starting to concentrate their efforts on actions that go beyond the embryonic stage of generating opportunities to access ICT (general IT infrastructure, 1:1 programs, cyber-centers, networks building, etc.). It also shows how countries on the same income level (mid-high) have run very different digital strategies which, in some cases, have led to high impact outcomes. The result of this research is a "MIL Readiness Index" proposal and a rich first mapping of the MIL enabling factors in the region

Trigohowilols A–G, Degraded Diterpenoids from the Stems of <i>Trigonostemon howii</i>

Two new degraded diterpenoids, trigohowilols A (<b>1</b>) and B (<b>2</b>), four new heterodimers, trigohowilols C–F (<b>3</b>–<b>6</b>), one new homodimer, trigohowilol G (<b>7</b>), and three known degraded diterpenoids (<b>8</b>–<b>10</b>) were isolated from the methanol extract of the stems of <i>Trigonostemon howii</i>. Compounds <b>1</b>–<b>7</b> were evaluated for their cytotoxic activity against five human tumor cell lines by an MTT assay, and trigohowilols E (<b>5</b>) and F (<b>6</b>) exhibited inhibitory activity with IC₅₀ values ranging from 2.33 to 12.57 μM. Moreover, compounds <b>1</b>–<b>6</b> showed weak antimicrobial activities (MIC values: 6.25–25 μg/mL) against <i>Staphylococcus aureus</i>, <i>Pseudomonas aeruginosa</i>, MRSA 92^#, and MRSA 98^# using a 2-fold dilution method

Trigoflavidols A–C, Degraded Diterpenoids with Antimicrobial Activity, from <i>Trigonostemon flavidus</i>

Trigoflavidols A (<b>1</b>) and B (<b>2</b>), tetranorditerpenoid dimers possessing a rearrangement skeleton with a spiroketal core moiety, and trigoflavidol C (<b>3</b>), a hexanorditerpenoid, have been isolated from <i>Trigonostemon flavidus</i> along with two known compounds. Compounds <b>1</b> and <b>2</b> showed moderate antimicrobial activities (MIC values: 3.12–6.25 μg/mL) against <i>Staphylococcus aureus</i>, 8^#MRSA, and 82^#MRSA, and <b>1</b>, <b>2</b>, and <b>5</b> showed weak activities (IC₅₀ values: 3.75–28.99 μM) against various human tumor cell lines

Bioactive Limonoid Constituents of <i>Munronia henryi</i>

Fourteen new limonoids, munronins A–N (<b>1</b>–<b>14</b>), and eight known limonoids (<b>15</b>–<b>22</b>) were isolated from the whole plants of <i>Munronia henryi</i>. The structures of the new compounds were elucidated by 2D NMR spectroscopy and mass spectrometry, and the structure of <b>8</b> was confirmed by single-crystal X-ray diffraction analysis. Compound <b>1</b> represents the first limonoid found with a novel 7-oxabicyclo[2.2.1]­heptane moiety produced by incorporating C-11 and C-14 via an oxygen atom. All compounds were evaluated for their anti-tobacco mosaic virus (TMV) activity and in vitro cytotoxicity against the human cancer HL-60, SMMC-7721, A-549, MCF-7, and SW-480 cell lines. Among them, compounds <b>2</b>, <b>8</b>, <b>9</b>, <b>10</b>, <b>11</b>, <b>12</b>, <b>18</b>, and <b>20</b> showed significant anti-TMV activity, with IC₅₀ values in the range 19.6–44.4 μg/mL. Compounds <b>1</b> and <b>18</b> exhibited cytotoxic effects for all five cancer cell lines, with IC₅₀ values between 0.4 and 4.8 μM

Identification of Ingol and Rhamnofolane Diterpenoids from <i>Euphorbia resinifera</i> and Their Abilities to Induce Lysosomal Biosynthesis

The phytochemical study of <i>Euphorbia resinifera</i> afforded 18 structurally diverse diterpenoids, including 14 new ingol-type diterpenoids, euphorblins A–N (<b>1</b>–<b>14</b>), a new rhamnofolane diterpenoid, euphorblin O (<b>15</b>), and three known analogues (<b>16</b>–<b>18</b>). The structures of these compounds were deduced using 2D NMR spectroscopy and NOE experiments. The structure of compound <b>1</b> was confirmed by single-crystal X-ray crystallography. The abilities of the compounds to enhance lysosomal biosynthesis were evaluated through LysoTracker Red staining. Among the 10 active compounds, compounds <b>2</b>, <b>4</b>, and <b>18</b> showed remarkable immunofluorescence strength, and their LysoTracker staining intensities were 155.9%, 143.5%, and 140.7%, respectively, greater than that of the control. A series of lysosomal genes were also found to be upregulated by these compounds, which further confirms their ability to induce lysosome biosynthesis and suggests that these diterpenoids have potential as lead compounds for the development of drugs for the treatment of lysosome-related diseases

Alkaloids with Different Carbon Units from <i>Myrioneuron faberi</i>

Three new <i>Myrioneuron</i> alkaloids, myrifamines A–C (<b>1</b>–<b>3</b>), with unique skeletons were isolated from <i>Myrioneuron faberi.</i> The absolute configuration of <b>1</b> was confirmed by single-crystal X-ray diffraction analysis, and the stereochemistry of the other two alkaloids was determined using a combination of ROESY experiments and calculated and experimental electronic circular dichroism spectra. Myrifamine C (<b>3</b>) is the first example of a symmetric dimer among the <i>Myrioneuron</i> alkaloids. Known alkaloids myrionamide (<b>4</b>) and schoberine (<b>5</b>) were also isolated, and experimental NMR and X-ray diffraction data suggest their structural revision. Compound <b>2</b> showed significant inhibitory activity toward the hepatitis C virus in vitro, with a therapeutic index (CC₅₀/EC₅₀) greater than 108.7

Cyclohexane-Fused Octahydroquinolizine Alkaloids from Myrioneuron faberi with Activity against Hepatitis C Virus

Investigation of the alkaloids from Myrioneuron faberi, a plant unique to China, gave four pairs of enantiomers (<b>1</b>–<b>4</b>). (±)-β-Myrifabral A (<b>1</b>) and (±)-α-myrifabral A (<b>2</b>) formed an inseparable mixture of anomers (cluster A), as did (±)-β-myrifabral B (<b>3</b>) and (±)-α-myrifabral B (<b>4</b>) (cluster B). Their structures were determined by X-ray diffraction and NMR analysis. Compounds <b>1</b>–<b>4</b> possessed novel cyclohexane-fused octahydroquinolizine skeletons and represent the first quinolizidine alkaloids from the genus Myrioneuron. The epimers of cluster A (<b>1</b> and <b>2</b>) were modified and separated. In vitro, clusters A and B and their derivatives inhibited replication of hepatitis C virus (HCV, IC₅₀ 0.9 to 4.7 μM) with cytotoxicity lower than that of telaprevir