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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Expresión de factor tisular y niveles séricos de anticuerpos antilipoproteína de baja densidad oxidada en el síndrome antifosfolipido primario

Rivera Gallego, Alberto 30 November 2000 (has links)
No description available.
62

Experiential Environmental Learning: A Case Study of Innovative Pedagogy in Baja Sur, Mexico

Schneller, Andrew Jon January 2008 (has links)
This mixed methods case study describes an innovative two-semester middle school environmental learning course that departs from traditional Mexican expository pedagogy through the incorporation of experiential and service learning. This research takes place in a small middle school in Pescadero, Baja California Sur, Mexico. The research approach utilized in the study adds to the handful of studies in this cross-disciplinary field by employing quantitative methodologies to measure course outcomes on student environmental knowledge, perceptions, and actions, while simultaneously qualitatively describing the behavioral, educational, environmental, and social experiences of students. This research employs Dewey's theories of experience -- as well as those of more contemporary authenticity theorists -- in order to identify the philosophies that advocate incorporating experiential pedagogy within the curriculum. Implications for Mexican educational policy, practical pedagogical applications, and theory are discussed.
63

Testing the role of Baja California generating biodiversity: A test case characterizing the population genetic structure of Cassin's auklet (Ptychoramphus aleuticus)

Wallace, Sarah 28 September 2012 (has links)
Characterizing the population genetic structure of a species can provide insight into isolating effects of local adaptation and genetic drift, and homogenizing effects of gene flow. The relative interplay between gene flow and genetic drift can indicate whether multiple conservation units are needed to preserve biodiversity. Baja California, Mexico is a biodiversity hotspot where many individuals are genetically differentiated from conspecific individuals breeding elsewhere. Cassin’s auklet (Ptychoramphus aleuticus), a zooplanktivorous seabird, breeds in colonies along the Pacific coast of North America. One subspecies, P. a. australe, is described from Baja California and another, P. a. aleuticus, is described from the rest of its range to the Aleutian Islands, Alaska. Many of the colonies throughout its range have been declining in numbers likely as a result of decreases in food availability in cold-water upwellings along the coast. The mitochondrial control region and eleven nuclear microsatellites were analyzed using programs based on coalescent and Bayesian theory to determine how the southern subspecies compares genetically to the main subspecies. First, population genetic structure was characterized throughout Cassin’s auklet’s breeding range using pairwise genetic differentiation indices, hierarchical analysis of variance, statistical parsimony and Bayesian clustering methods. The two subspecies were genetically differentiated but individuals breeding in the Channel Islands were more genetically similar to P. a. australe individuals. Population genetic differentiation was not evident within the two genetic groups. Second, gene flow between the two genetic groups was estimated using coalescent and Bayesian methods. Significant gene flow was estimated from the northern group (Aleutian Islands to Southeast Farallon Islands) into the southern group (Channel Islands to San Benito Island) but not from the southern group into the northern group since the time of divergence, possibly as a result of the non-breeding distribution. Results show that the two genetic populations diverged recently and the populations have experienced a recent population change in size. Restrictions in home range and foraging range may cause population genetic differentiation, resulting in two distinct management units. Genetic differentiation of the southern population provides support for Baja California and southern California being a biodiversity hotspot. / Thesis (Master, Biology) -- Queen's University, 2012-09-28 14:02:24.007
64

THE VALUE OF A PLACE: DEVELOPMENT POLITICS ON THE EAST CAPE OF BAJA CALIFORNIA SUR, MEXICO

Anderson, Ryan B. 01 January 2014 (has links)
This research explores the politics of development on the East Cape of Baja California Sur, Mexico. Based upon twelve months of ethnographic research and participant observation, primarily in the coastal community of Cabo Pulmo, the researcher investigates and documents how local residents respond to the social and political implications of impending mass tourism development in the region. Rising land values, real estate speculation, and intensifying conflicts over land ownership were some of the earliest symptoms of this process. The central argument is that social conflicts over development are often based in deeper, fundamental political struggles over land—and the ability to participate in the development process itself. This represents an important contribution to our understanding of the political and social dynamics of development, which, in the literature, are often framed in abstract terms of debate that remain highly detached from the lived realities of the people who stand to lose the most if development goes awry. Using the concepts of value, development, community, and sustainability as theoretical starting points, this research argues that conflicts over development should be seen as struggles for inclusion and participation above all else. Ultimately, the conclusion of this research is that conflicts over ownership of and access to land continue to impede alternative forms of development that seek to avoid the negative social, political, and economic consequences of traditional mass tourism models.
65

Biographical factors and their use as predictors of tenure and absenteeism in a Tijuana maquiladora

Ochoa, Ricardo. January 1990 (has links)
Thesis (Ph. D.)--United States International University, 1990. / Includes bibliographical references (leaves 124-143).
66

Elusive Edens linking local needs to nature protection in the coastal lagoons of Baja California Sur, Mexico /

Young, Emily Harriet. January 1995 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1995. / Vita. Includes bibliographical references (leaves 287-313).
67

Enforcing boundaries globalization, state power and the geography of cross-border consumption in Tijuana, Mexico /

Murià Tuñón, Magalí. January 2010 (has links)
Thesis (Ph. D.)--University of California, San Diego, 2010. / Title from first page of PDF file (viewed March 30, 2010). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 384-401).
68

Eye-Tracking Investigations Exploring How Students Learn Geology from Photographs and The Structural Setting of Hydrothermal Gold Deposits in the San Antonio Area, B.C.S., MX

January 2011 (has links)
abstract: Geoscience educators commonly teach geology by projecting a photograph in front of the class. Geologic photographs often contain animals, people, and inanimate objects that help convey the scale of features in the photograph. Although scale items seem innocuous to instructors and other experts, the presence of such items is distracting and has a profound effect on student learning behavior. To evaluate how students visually interact with distracting scale items in photographs and to determine if cueing or signaling is an effective means to direct students to pertinent information, students were eye tracked while looking at geologically-rich photographs. Eye-tracking data revealed that learners primarily looked at the center of an image, focused on faces of both humans and animals if they were present, and repeatedly returned to looking at the scale item (distractor) for the duration an image was displayed. The presence of a distractor caused learners to look at less of an image than when a distractor was not present. Learners who received signaling tended to look at the distractor less, look at the geology more, and surveyed more of the photograph than learners who did not receive signaling. The San Antonio area in the southern part of the Baja California Peninsula is host to hydrothermal gold deposits. A field study, including drill-core analysis and detailed geologic mapping, was conducted to determine the types of mineralization present, the types of structures present, and the relationship between the two. This investigation revealed that two phases of mineralization have occurred in the area; the first is hydrothermal deposition of gold associated with sulfide deposits and the second is oxidation of sulfides to hematite, goethite, and jarosite. Mineralization varies as a function of depth, whereas sulfides occurring at depth, while minerals indicative of oxidation are limited to shallow depths. A structural analysis revealed that the oldest structures in the study area include low-grade to medium-grade metamorphic foliation and ductile mylonitic shear zones overprinted by brittle-ductile mylonitic fabrics, which were later overprinted by brittle deformation. Both primary and secondary mineralization in the area is restricted to the later brittle features. Alteration-bearing structures have an average NNW strike consistent with northeast-southwest-directed extension, whereas unaltered structures have an average NNE strike consistent with more recent northwest-southeast-directed extension. / Dissertation/Thesis / Ph.D. Geological Sciences 2011
69

Late Quaternary Normal Faulting and Hanging Wall Basin Evolution of the Southwestern Rift Margin From Gravity and Geology, B.C.S., MX and Exploring the Influence of Text-Figure Format on Introductory Geology Learning

January 2011 (has links)
abstract: An array of north-striking, left-stepping, active normal faults is situated along the southwestern margin of the Gulf of California. This normal fault system is the marginal fault system of the oblique-divergent plate boundary within the Gulf of California. To better understand the role of upper-crustal processes during development of an obliquely rifted plate margin, gravity surveys were conducted across the normal-fault-bounded basins within the gulf-margin array and, along with optically stimulated luminescence dating of offset surfaces, fault-slip rates were estimated and fault patterns across basins were assessed, providing insight into sedimentary basin evolution. Additionally, detailed geologic and geomorphic maps were constructed along two faults within the system, leading to a more complete understanding of the role of individual normal faults within a larger array. These faults slip at a low rate (0.1-1 mm/yr) and have relatively shallow hanging wall basins (~500-3000 m). Overall, the gulf-margin faults accommodate protracted, distributed deformation at a low rate and provide a minor contribution to overall rifting. Integrating figures with text can lead to greater science learning than when either medium is presented alone. Textbooks, composed of text and graphics, are a primary source of content in most geology classes. It is essential to understand how students approach learning from text and figures in textbook-style learning materials and how the arrangement of the text and figures influences their learning approach. Introductory geology students were eye tracked while learning from textbook-style materials composed of text and graphics. Eye fixation data showed that students spent less time examining the figure than the text, but the students who more frequently examined the figure tended to improve more from the pretest to the posttest. In general, students tended to examine the figure at natural breaks in the reading. Textbook-style materials should, therefore, be formatted to include a number of natural breaks so that learners can pause to inspect the figure without the risk of losing their place in the reading and to provide a chance to process the material in small chunks. Multimedia instructional materials should be designed to support the cognitive processes of the learner. / Dissertation/Thesis / Ph.D. Geological Sciences 2011
70

La santé reproductive des adolescentes en Basse Californie : résultat d'une enquête auprès des ménages / The reproductive health of adolescents in Baja California : results of a household survey

Palma Cabrera, Yolanda 19 December 2013 (has links)
Le développement de cette étude part de l’observation des données de différentes sources au sujet de la fécondité des adolescentes de Basse-Californie (Mexique), qui a atteint un des plus hauts niveaux parmi les entités fédérées. Cet état est caractérisé par le fait que pratiquement la totalité de sa population se situe dans un territoire avec un contact quotidien potentiel avec la Californie aux Etats-Unis. D’autre part, il s’agit d’un état avec une forte immigration interne de population en provenance de plusieurs entités du pays. Un autre aspect qui caractérise à l’entité se réfère au comportement conservateur de ses autorités. La Basse-Californie est l’un des états qui a présenté des normes parmi les plus restrictives dans l’application des lois ainsi qu’un faible intérêt dans l’élaboration de stratégies qui cherchent à résoudre ce problème à partir des caractéristiques de l’entité. Dans ce contexte de forte immigration interne, d’influence potentielle des Etats-Unis et de gouvernements très conservateurs, la question centrale posée par cette étude renvoie aux niveaux de fécondité, aux variables qui dans une grande mesure la détermine en Basse-Californie, et aux causes potentielles de cette association en partant des théories qu’ont apportées différents auteurs. La méthodologie utilisée dans cette étude fut celle de l’enquête de probabilité au sein de ménages comprenant des femmes de 18 à 29 ans. L’enquête de Basse-Californie provient d’un projet dont l’initiative a surgi du Collège de la Frontière Nord en réponse à un appel d’offre de CONACYT, sous la direction de l’auteure du travail présenté ici. / This study was developed from the observation of data related to fertility of adolescents in Baja California, Mexico. This state presents high levels for this indicator compared to the rest of Mexico; most of its population lives close to the border with the United States and the state receives large numbers of immigrants from Southern Mexico. Governmental officials in Baja California hold conservative beliefs, therefore, regulations related to this topic are restrictive and there has been a low interest in designing strategies based on the characteristics of the state that could solve and prevent the high adolescent fertility. Within this context, high internal immigration, U.S. influence, conservative governments, the main question of this study deals with estimating the levels of fertility, which variables are determining it and finding out the relation between the fertility and its variables. The methodology used in this study was based on a probabilistic survey of women between 18 and 29 years old. This Baja California survey was the result of a project carried out at El Colegio de la Frontera Norte and financed by CONACYT, under my leadership.

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