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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.
1

Learning strategies of students with different cpgnitive styles in a hypermedia environment

Yecan, Esra. Supervisor : Çağıltay, Kürşat. January 2005 (has links) (PDF)
Thesis (M.S.) -- Middle East Technical University, 2005. / Keywords: Hypermedia, learning with hypermedia individual differences individual differences in hypermedia environment cognitive styles learning strategies domain knowledge computer competency
2

A DECISION ANALYSIS FOR A COMPREHENSIVE OPERATIONAL SAHELIAN MODEL OF OPPORTUNITY (COSMO): AN EDUCATIONAL POLICY MODEL FOR DEVELOPING HUMAN RESOURCES IN THE SAHEL REGIONS

Unknown Date (has links)
Deforestation and water pollution aid drought and desertification in the Sahel region. This study therefore focuses on: / (A) An educational decision analysis for water exploration and alternative animal raising in the Sahel region. Raiffa's educational decision model was used to test a decision-making procedure for water exploration involving three sources or types of water and also two alternatives of animal raising. / From the study, a water exploring site which is soaking and a drilled well system with a hand pump are the best alternatives. A ranch system is also preferred to a nomadic system. / (B) An educational policy model as a human development tool. The model was based on the results of this study and represents a network of activities and possible results. / Source: Dissertation Abstracts International, Volume: 43-06, Section: A, page: 1754. / Thesis (Ph.D.)--The Florida State University, 1982.
3

Probing lipid membrane electrostatics

January 2009 (has links)
The electrostatic properties of lipid bilayer membranes play a significant role in many biological processes. Atomic force microscopy (AFM) is highly sensitive to membrane surface potential in electrolyte solutions. With fully characterized probe tips, AFM can perform quantitative electrostatic analysis of lipid membranes. Electrostatic interactions between Silicon nitride probes and supported zwitterionic dioleoylphosphatidylcholine (DOPC) bilayer with a variable fraction of anionic dioleoylphosphatidylserine (DOPS) were measured by AFM. Classical Gouy-Chapman theory was used to model the membrane electrostatics. The nonlinear Poisson-Boltzmann equation was numerically solved with finite element method to provide the potential distribution around the AFM tips. Theoretical tip-sample electrostatic interactions were calculated with the surface integral of both Maxwell and osmotic stress tensors on tip surface. The measured forces were interpreted with theoretical forces and the resulting surface charge densities of the membrane surfaces were in quantitative agreement with the Gouy-Chapman-Stern model of membrane charge regulation. It was demonstrated that the AFM can quantitatively detect membrane surface potential at a separation of several screening lengths, and that the AFM probe only perturbs the membrane surface potential by <2%. One important application of this technique is to estimate the dipole density of lipid membrane. Electrostatic analysis of DOPC lipid bilayers with the AFM reveals a repulsive force between the negatively charged probe tips and the zwitterionic lipid bilayers. This unexpected interaction has been analyzed quantitatively to reveal that the repulsion is due to a weak external field created by the internai membrane dipole moment. The analysis yields a dipole moment of 1.5 Debye per lipid with a dipole potential of +275 mV for supported DOPC membranes. This new ability to quantitatively measure the membrane dipole density in a noninvasive manner will be useful in identifying the biological effects of the dipole potential. Finally, heterogeneous model membranes were studied with fluid electric force microscopy (FEFM). Electrostatic mapping was demonstrated with 50 nm resolution. The capabilities of quantitative electrostatic measurement and lateral charge density mapping make AFM a unique and powerful probe of membrane electrostatics.
4

The God within: Rituals, beliefs and experiences of New Age seekers in a large Southwestern city

McIlwaine, Mary Kris January 2001 (has links)
This case study of the New Age movement uses ethnographic methods to acquire and analyze data on a sample of movement participants in a large Southwestern U.S. city. The study provides an ecology of the local manifestation of the larger movement, looking at multiple New Age institutes, periodicals, radio broadcasts, churches, commercial expositions; participants; and rituals, beliefs and experiences of participants. The study contributes to scholarship in the sociology of religion, social movements, and general sociological theory. This study elaborates empirically and theoretically several key principles and processes in the sociology of religion. First, participants engage in five main types of rituals---regarding material recognition, healing, group-focus, spirit connections and psyche reorientation. Second, participants' most significant belief is that of "perfectionistic monism," with derivative beliefs diagnosing ego as humans' problem, prescribing awareness to ameliorate ego's ill effects, and implying that desirable results (concerning efficacy, morality, wellbeing) arise from believing along these lines. Third, participants emphasize experiences over doctrine, positively experience almost all stimuli in their lives, and benefit from a significant overlap between their movement's ideal and real cultures. This study examines rituals, beliefs and experiences to ask three questions social movements scholars sometimes neglect: How does ritual action contribute to movement persistence? How do movement participants see themselves and the world? How does movement involvement affect participants? It finds rituals to contribute to "religious value," the "perfectionistic monism" belief and the "religious logic" of the movement to contribute to participant identity, and all three of these things to contribute to movement persistence. At a more general level, the study of the interrelatedness of rituals, beliefs and experiences expands analytic possibilities for social movements scholars. Moreover, the inclusion of religious movements in the study of social movements can refine theorizations of the concept of social movement. Finally, the study suggests further questions for general sociological theory via its finding that New Agers are explicitly aware of the part they play in the social construction of reality. This finding should spur sociologists to further examine the relationship between actor awareness and sustainability of institutions that self-aware actors build.
5

X-ray scattering with momentum transfer in the plane of membrane: Application to gramicidin organization

He, Ke January 1993 (has links)
We demonstrate a technique of measuring x-ray (or neutron) scattering with the momentum transfer parallel to the plane of membrane. This technique allows us to investigate the lateral organization of protein and peptide in the membrane. To resolve the question of whether gramicidin (GA) forms lateral aggregates, samples of GA in dilauroylphosphatidycholine (DLPC) bilayers (molar ratio 1:10) were investigated. Very clear scattering signals of GA were obtained, even for the peptide without a heavy atom attached. The experiment showed that the gramicidin channels did not aggregate and were randomly distributed in the membrane. The non-conducting state of gramicidin channel was also investigated. We use a synthetic GA analogue in which the formyl group of natural GA is replaced by a BOC group. The in-plane scattering measurements show that the gramicidin channel closes by dissociation into two monomers, each remains embedded and freely diffuses in its own monolayer.
6

A response to Christian critique of psychology as a religion

Bukaty, Peter James January 2001 (has links)
Modern psychology and psychotherapy for some, has become a functional religion. Certain Christian scholars have employed deontological ethics of mutuality and obligation to critique the implicit ethical egoist perspective of humanistic, Jungian and ego psychologies as scholars such as Don Browning believe that therapists and pastoral counselors have appropriated clinical psychologies without examining their implicit ethical egoist orientations. They believe that an ethic of generativity best exemplifies the fit between modern psychology and Christian theology. So-called "generative man" is the preferred archetype to "productive man" or "psychological man." However, the aretaic ethics of individuation and self-actualization have paradoxical utilitarian benefits for the community. It is argued that the process of narcissism associated with individuation is necessary before one can authentically embrace a deontological ethic of mutuality.
7

Investigation of pygmy sperm whale (Kogia breviceps ) populations in the southeastern United States using stable isotopes of carbon, nitrogen, and oxygen in teeth

Montey, Nicole R. 12 May 2015 (has links)
<p> The pygmy sperm whale (<i>Kogia breviceps</i>) is currently the second-most commonly stranded cetacean in the Southeastern United States (SEUS), but information concerning their population structure is severely limited. This study utilized stable isotope analysis to investigate the possible migratory patterns and population structure of <i>K. breviceps </i> among six different regions in the SEUS. Combined growth layers from different regions of the teeth were subsampled via dental drill and analyzed representing four different age classes: calf, juvenile, sub-adult, and adult, as well as four yearlings that had stranded with their mothers. Stable isotope ratios of carbon and nitrogen were measured in the organic component of 46 teeth, and oxygen isotope ratios were measured in the inorganic (hydroxyapatite) component of 21 teeth obtained from stranded individuals. There was a high degree of individual variability in &delta;<sup>13</sup>C, &delta;<sup> 15</sup>N, and &delta;<sup>18</sup>O resulting in no significant differences between the six different regions: South Carolina, Georgia, Northern, Central, and Southern Florida, and the Gulf of Mexico. Differences between the age classes were significant for &delta;<sup>13</sup>C and &delta;<sup> 15</sup>N. Adults exhibited significantly more negative &delta;<sup>13 </sup>C than subadults. These results support a previously hypothesized inshore-offshore migration for <i>Kogia breviceps.</i> Yearlings displayed significantly higher &delta;<sup>15</sup>N values than all other age classes due to nursing. A slight increase in &delta;<sup>15</sup>N from juvenile to adult supports a possible ontogenetic shift in the trophic level of prey. Results from this study provide the first carbon and nitrogen isotope values from different age classes of pygmy sperm whales as well as the first reported oxygen isotopes values for this species.</p>
8

Pattern formation in actin gels a study in the mechanics of gels formed by the important cytoskeletal protein actin, especially as applied to cellular motility /

Balter, Ariel. January 2005 (has links)
Thesis (Ph.D.)--Indiana University, Dept. of Physics, 2005. / Source: Dissertation Abstracts International, Volume: 66-03, Section: B, page: 1508. Adviser: Jay X. Tang. "Title from dissertation home page (viewed Nov. 2, 2006)."
9

Spatially Resolved, Highly Multiplexed RNA Profiling in Single Cells

Chen, Kok Hao 02 May 2016 (has links)
The transcriptome of a cell contains a wealth of information about the cell’s current state and its recent history. System-wide analyses of the copy number and localization of RNAs in single cells promise to transform our understanding of many areas of biology, such as the origin and consequences of cellular heterogeneity, functions and mechanisms underlying sub-cellular localization of transcripts, and organization of cell types in tissues. Fluorescent in situ hybridization (FISH) based approaches for measuring single-cell gene expression offer high spatial resolution and single molecule sensitivity, but lack throughput in comparison with sequencing based methods. In the first part of this thesis, we present multiplexed, error robust FISH (MERFISH) for transcriptome imaging in single cells. We labeled each cellular RNA with multiple complementary oligonucleotide probes, which contain additional readout sequences. Each RNA species is encoded with a unique combination of readout sequences. We then identified these RNAs by using successive rounds of hybridization and imaging, with a different fluorescently labeled readout probe each round. This combinatorial labeling scheme allows the number of detectable RNA species to grow exponentially with the number of hybridization rounds, but the effect of readout errors also increases. By utilizing error-robust encoding schemes similar to those common in digital electronics, we are able to match the measured sequence of on/off fluorescence signals from individual RNAs to their assigned barcodes with high efficiency and minimal error. In the second part of this thesis, we optimize the performance of localization based super-resolution microscopy by conducting a systematic characterization of the photo-switching properties of 26 organic dyes. These properties, which include the photons per switching event, on-off duty cycle, photostability, and number of switching cycles, largely dictate the quality of super-resolution images. Our study identified the top performing dyes in each fluorescent channel, allowing us to perform super-resolution imaging in four colors. We envision that by combining multi-color super resolution microscopy with our multiplexed RNA imaging approach, we can visualize all the RNA content, the transcriptome, of a cell in situ. The ability to perform spatially-resolved transcriptomic analysis of cells and tissues will dramatically improve our abilities to understand biology and disease. / Chemistry and Chemical Biology
10

L'invenzione Della Montagna. Significati E Valori Dello Spazio Nel Fascismo E Nella Resistenza

Boscolo Berto, Angela 17 July 2015 (has links)
Questa tesi discute il ruolo, la funzione e i significati attribuiti alla montagna in due periodi capitali della storia del Novecento: il fascismo e la Resistenza. Nella prima sezione di questa ricerca ripercorro alcune tappe significative della politica ambientale fascista che aiutano a comprendere l’impatto che il regime ha avuto sul paesaggio montano italiano. Con le sue bonifiche, le migliorie agrarie e il rimboschimento ma anche le semine degli alberi, le cerimonie commemorative nei sacrari della Grande Guerra e le attività sponsorizzate dal nuovo turismo di massa, il fascismo vede nel territorio un originale strumento di autorappresentazione e una grande occasione nel contesto mondiale per definirsi in chiave moderna. Nelle stesse montagne che il fascismo conquista dopo l’armistizio del ‘43 andranno migliaia di partigiani ma con scopi molto diversi da quelli che si erano prefissati i gerarchi del regime, cambiando radicalmente la semantica stessa dell’andare in montagna. Nella seconda parte di questo studio rivisito alcune grandi opere degli scrittori della Resistenza (Fenoglio, Meneghello, Calvino, ma anche Pavese) dalle quali si evince come la memoria del paesaggio della guerra, alla prova col testo, resiste la canonica funzione di cornice naturalistica per incarnarsi in luogo dal quale emerge la coscienza dello scrittore e a cui vengono attribuiti inediti significati simbolici. È il nuovo valore di questa montagna, per la prima volta nella storia letteraria italiana vera protagonista del racconto, a essere qui scandagliato, sia come esperienza concreta sia come metafora dell’esistenza. / Romance Languages and Literatures

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