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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.
11

A Phenomenological-Hermeneutic Study of Adept Practitioners' Experiences of Focusing

Nokes-Malach, Sarah 26 July 2012 (has links)
This study presents a qualitative analysis of six accounts of focusing, a method of embodied reflection. Six expert practitioners were interviewed, and each participant`s account was brought under two rounds of analysis. First, a modified descriptive phenomenological analysis was performed on a portion of the interview in which the participant described a particular focusing experience. This was followed by an interpretive phenomenological analysis of the participant`s interview as a whole. Analyses resulted in the identification of explicit and implicit themes that were constitutive of focusing experiences across participants. Several themes that were identified include: the importance of social support and validation for experiences that depart from the norms and values of materialist culture, the exquisite gentleness and receptivity of the focusers` attitude toward their experiences, and the dialogical qualities of the practice. The details and significance of the dialogue, which is a synesthetic exchange between the focuser and responses arising in her perceptual field, is explored in the discussion. Attention is paid to the fluid and at times ambiguous self-other experience suggested by the dialogue, and an archetypal framework for interpreting this dialogue is introduced. Additionally, the two phenomenological methods employed are reviewed and compared for their relative merit in the study of focusing. / McAnulty College and Graduate School of Liberal Arts / Clinical Psychology / PhD / Dissertation
12

Subwavelength Focusing via Holographic Metallic Screens

Wong, Alex Man Hon 22 September 2009 (has links)
In this work we investigated a new class of subwavelength focusing device, termed the holographic metallic screen. We first proposed a generalized procedure which takes a holographic record of a subwavelength electromagnetic field distribution. Subsequently we synthesized this record using two types of holographic metallic screen – the slot antenna hologram (SAH) and the resonant slot antenna hologram (RSAH). We designed both holograms and evaluated their performances through full-wave simulations, and experimentally demonstrated subwavelength focusing for the RSAH. Simulations and experiments illustrated various attractive properties of the subwavelength focusing RSAH, which included (a) a tighter focal width than a single subwavelength aperture; (b) a focal field amplitude surpassing the incident field amplitude; and (c) a simple design scalable to a wide range of frequencies from microwave to optical. These properties should serve to motivate further development on the holographic metallic screen towards potential applications such as sensing, imaging and lithography.
13

Subwavelength Focusing via Holographic Metallic Screens

Wong, Alex Man Hon 22 September 2009 (has links)
In this work we investigated a new class of subwavelength focusing device, termed the holographic metallic screen. We first proposed a generalized procedure which takes a holographic record of a subwavelength electromagnetic field distribution. Subsequently we synthesized this record using two types of holographic metallic screen – the slot antenna hologram (SAH) and the resonant slot antenna hologram (RSAH). We designed both holograms and evaluated their performances through full-wave simulations, and experimentally demonstrated subwavelength focusing for the RSAH. Simulations and experiments illustrated various attractive properties of the subwavelength focusing RSAH, which included (a) a tighter focal width than a single subwavelength aperture; (b) a focal field amplitude surpassing the incident field amplitude; and (c) a simple design scalable to a wide range of frequencies from microwave to optical. These properties should serve to motivate further development on the holographic metallic screen towards potential applications such as sensing, imaging and lithography.
14

Development of Isoelectric Focusing Techniques for Protein Analyses

Zhan, Yanwei 23 September 2008 (has links)
Isoelectric focusing (IEF) is a powerful approach in separations of zwitterionic substances such as proteins, peptides and amino acids. It is important in proteomic research. Generally, in IEF, carrier ampholytes (CAs) are necessary to establish a stable pH gradient. However, CAs also bring attendant problems such as a decrease in detection sensitivity and suppression of ionization of analytes in mass spectrometry (MS) detection. It is desirable to build a pH gradient without using CAs. A simple slab based design was developed to establish a pH gradient using the electrolysis of water and the strength of free flow electrophoresis (FFE). The simple and robust CA free FFE-IEF design was applied in protein fractionation. In capillary format, capillary isoelectric focusing (CIEF), coupled to MS is a promising hyphenated technique for biomolecular analysis based on the combination of the high separation power of CE and the high specificity of MS. Coupling of the instruments is usually achieved with a coaxial sheath liquid interface, which decreases the detection sensitivity because of the dilution of sample by the sheath liquid. In this project, nano-electrospray, a sheathless interface, was used for coupling. Additionally, another major challenge is the presence of CAs which suppresses the ionization of analytes and contaminates the MS. In order to complete this project, a microcross union was chosen to couple CIEF with MS. A makeup solution was introduced to dilute the concentration of CAs after IEF to assist the ionization for MS detection. The makeup solution could replace the sheath liquid and could be maintained at a low flow rate so that nanoelectrospray could be performed. Monoliths can be described as integrated continuous porous separation media for micro scale separation columns. CAs were immobilized at different positions in the column according to their pIs, generating a monolithic immobilized pH gradient (M-IPG). In this project, carrier ampholytes was immobilized in poly (GMA-co-EDMA) based monolithic capillary and poly (GMA-co-acrylamide) based monolithic capillary to form a pH gradient. Two proteins were separated by IEF, which was implemented in poly (GMA-co-acrylamide) based monolithic capillary without CAs. The interface to MS was performed following the use of a microcross union as described previously. No typical noise of CAs was observed in the MS spectrum.
15

Development of Isoelectric Focusing Techniques for Protein Analyses

Zhan, Yanwei 23 September 2008 (has links)
Isoelectric focusing (IEF) is a powerful approach in separations of zwitterionic substances such as proteins, peptides and amino acids. It is important in proteomic research. Generally, in IEF, carrier ampholytes (CAs) are necessary to establish a stable pH gradient. However, CAs also bring attendant problems such as a decrease in detection sensitivity and suppression of ionization of analytes in mass spectrometry (MS) detection. It is desirable to build a pH gradient without using CAs. A simple slab based design was developed to establish a pH gradient using the electrolysis of water and the strength of free flow electrophoresis (FFE). The simple and robust CA free FFE-IEF design was applied in protein fractionation. In capillary format, capillary isoelectric focusing (CIEF), coupled to MS is a promising hyphenated technique for biomolecular analysis based on the combination of the high separation power of CE and the high specificity of MS. Coupling of the instruments is usually achieved with a coaxial sheath liquid interface, which decreases the detection sensitivity because of the dilution of sample by the sheath liquid. In this project, nano-electrospray, a sheathless interface, was used for coupling. Additionally, another major challenge is the presence of CAs which suppresses the ionization of analytes and contaminates the MS. In order to complete this project, a microcross union was chosen to couple CIEF with MS. A makeup solution was introduced to dilute the concentration of CAs after IEF to assist the ionization for MS detection. The makeup solution could replace the sheath liquid and could be maintained at a low flow rate so that nanoelectrospray could be performed. Monoliths can be described as integrated continuous porous separation media for micro scale separation columns. CAs were immobilized at different positions in the column according to their pIs, generating a monolithic immobilized pH gradient (M-IPG). In this project, carrier ampholytes was immobilized in poly (GMA-co-EDMA) based monolithic capillary and poly (GMA-co-acrylamide) based monolithic capillary to form a pH gradient. Two proteins were separated by IEF, which was implemented in poly (GMA-co-acrylamide) based monolithic capillary without CAs. The interface to MS was performed following the use of a microcross union as described previously. No typical noise of CAs was observed in the MS spectrum.
16

A study on the emotional management of the student teacher: A Focusing-oriented approach

Chen, Kuang-ling 06 July 2004 (has links)
This study was designed to examine the effects of a Focusing-oriented emotional management method for the student teacher. This study was divided into three parts. The first part of this study was designed to understand how forty-six student teachers managed their emotional distress in life. The second part of this study was designed to examine the effects of the Focusing-oriented emotional management method for the twenty student teachers who participated in this part of the study. The third part of this study was designed to examine the six months follow-up effects for one of the twenty student teachers who participated in the second part of this study. The results of this study suggested that the Focusing-oriented emotional management method is a helpful tool for the student teachers in managing their emotional life.
17

The real-time image focusing technique via DVD pickup head

Chiu, Shao-Chun 16 July 2007 (has links)
Due to maturity of experimental technology in recent years, automatic optical inspection (AOI) is used in many industrial applications to replace visual inspection with high-speed and reliable characteristics. Because standard industrial AOI instruments are very expensive, this work introduces a low-cost and high performance AOI instrumentation technique for industrial applications. In this study, we develop an image auto focusing system based on the pickup head of DVD player. We alter the optical path of pickup head and integrate the CCD camera in this system. The idea is to use focus error signal in the linear focus region to estimate the distance between pickup head and object surface. In addition, a capacitance gauging instrument is used to measure the displacement. A PC based control law is then developed by using the PZT to drive the auto focusing system. By setting up such a low-cost system, the experimental results show that the time required for focusing performance is within 0.4s in most cases while the longest focusing time is about 1s. It is hoped that the results of this study can be implemented for real industrial AOI applications.
18

Microfluidic electrochemical flow cells : design, fabrication, and characterization /

Cabrera, Catherine Regina. January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 127-134).
19

APPLICATIONS OF DYNAMIC ISOELECTRIC/ANISOTROPY BINDING LIGAND ASSAY FOR PROTEOMIC RESEARCH

Pueblo, Hanna Elizabeth 01 May 2012 (has links)
The work presented in this dissertation centers around the development of analytical tools for the study of advanced proteomics. Section 1 of this work reviews the need for high efficiency protein separation techniques. Dynamic isoelectric focusing (DIEF) is new technique similar to capillary isoelectric focusing (CIEF) invented by Dr. Luke Tolley at Southern Illinois University Carbondale. Using DIEF, the electric field inside the separation capillary can be modified using high voltage electrodes, additional to the anode and cathode, to control the depth and shape of the resulting pH gradient. By changing the pH gradient, the location and width of focused protein bands can be controlled. As a new analytical technique, the development of DIEF required the design and fabrication of special holders which allow for electrical connections to be made at lengths along the separation capillary. These holders were also designed to have a removable section of capillary to extract very specific pH range proteins from high-resolution separations. Higher throughput DIEF systems were investigated, as well as multiplexed DIEF systems. Section 2 covers the topic of dynamic isoelectric/anisotropy ligand binding assay (DIABLA). DIABLA is a new method used to identify proteins in a complex sample that bind to a known molecule. DIABLA has the potential to be used in two complimentary ways, discovery mode and scanning mode. Both modes are accomplished by using DIEF, followed by fluorescence anisotropy as a sensitive detection method. This allows the entire length of capillary to be scanned to identify areas of non-zero anisotropy, which indicate binding interactions between the protein and target molecule. The binding protein(s) can then be extracted using the removable section of capillary from the DIEF holder, and can be identified by using a second dimension analysis, such as LC/MS/MS. DIABLA was verified in a series of proof-of-concept experiments in both discovery and scanning modes. These experiments involved fluorescently tagging proteins that were focused in the presence of a ligand tagged with a different fluorophore. The usefulness of DIABLA as a separation technique was demonstrated in four specific analyses of complex protein samples in Chapter 10.
20

Glycosylation of immunoglobulin G in cerebrospinal fluid and multiple sclerosis

Rogers, Stephen January 2001 (has links)
The glycosylation features of CSF oligoclonal IgG, and possible changes in N-glycans of CSF IgG in multiple sclerosis (MS) were studied. After isoelectric focusing (IEF) of CSF, bands were detected using biotinylated lectins and avidin-horseradish peroxidase. Concanavalin A (Con A) binding showed that mannose exists throughout the pH range of oligoclonal IgG. Sambucus nigra antigen (SNA) bound acidic and neutral oligoclonal IgG only, suggesting that alkaline oligoclonal IgG is deficient in sialic acid. Deglycosylation of CSF IgG using peptide-N-glycosidase F suggested that the range of isoelectric points of oligoclonal IgG bands is not due to carbohydrate differences alone. Lectin immunoassays, whereby protein A purified IgG was captured by anti-IgG coated tubes and probed using a range of biotinylated lectins, were used to compare 13 CSF samples from MS patients with 14 control samples. With Con A binding, a significantly higher mean and larger variance was found for the MS group (t-test: P < 0.05). Con A binding correlated with CSF [IgG]/[total protein]% (r=0.390; P=0.0443). Using HPLC to separate oligosaccharides released from IgG by hydrazinolysis and labelled with 2-aminobenzamide, glycans were determined in 7 CSF samples with oligoclonal IgG, and 6 CSF samples without. The ratio of the peak for biantennary fucosylated agalactosyl glycans to total monogalactosylated glycan peaks was lower for the oligoclonal IgG samples (t-test: P=0.0141). The overall results suggested that glycosylation changes occur in CSF IgG in MS, and that oligoclonal IgG contains less sialic acid but more galactose than polyclonal IgG.

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