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DAS or Severe PI: Issues of Professional ValidityGrimes, S., Lassiter, L., Williams, A. Lynn 01 January 2000 (has links)
No description available.
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The roles and regulation of phosphatidylinositol 3,5-bisphosphates in mammalsZhang, Yanling 01 January 2008 (has links)
Phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2] is a low-abundance signaling lipid important for the maintenance of the endomembrane system and selected membrane trafficking pathways. In yeast, in response to hyperosmotic stress, PI(3,5)P2 levels rise more than 20-fold in 5 minutes, and return to near basal levels in 30 minutes. This transient change suggests that PI(3,5)P2 levels are tightly regulated and may be involved in signaling a response to stress. In yeast, PI(3,5)P2 is synthesized through phosphorylation of PI(3)P by the PI(3)P 5-kinase Fab1. Loss of PI(3,5)P2 in yeast causes swollen vacuoles, defective retrograde trafficking from the vacuole, defective vacuole acidification, and mis-localization of a subset of vacuole lumenal proteins.
In yeast, Vac14 is a regulator of PI(3,5)P2 levels. Mammalian Vac14 and Fab1 are found in the same complex. To study the physiological significance of PI(3,5)P2, a mouse strain was generated with the Vac14 gene disrupted by a gene-trap genomic insertion. Vac14 protein was not detectable in mutant mice. In fibroblasts cultured from the mutant mice, PI(3,5)P2 and PI(5)P are decreased to 42% and 44% of the corresponding wild-type levels, respectively. The mutant mouse brains exhibit spongiform-like morphology. Cytoplasmic vacuoles are found in neuronal cell bodies of the olfactory bulb, trigeminal ganglion, and dorsal root ganglion. Non-neural tissues appear largely normal. Similar vacuoles are also found in cultured neurons and fibroblasts. In fibroblasts, these vacuoles are formed from swelling of late endosomes/lysosomes. Some early endosomes are also enlarged. A population of cation-independent mannose-6-phosphate receptor (CI-M6PR), which recycles between endosomes and the trans-Golgi network (TGN), is trapped in early and late endosomes, indicating a block in endosome-to-TGN trafficking.
These results suggest that: 1) Neurons are acutely sensitive to loss of PI(3,5)P2. 2) In mammals, PI(3,5)P2 is required for the morphology of late endosomes/lysosomes and retrograde trafficking from endosomes to the TGN. The first conclusion is supported by another mouse strain with a retro-transposon inserted in the Fig4 gene. Fig4 is another regulator of PI(3,5)P2 levels. Similar neurodegeneration was observed in the Fig4 mutant mice.
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Personality Factors and Nuclear Power Plant Operators: Initial License SuccessDeVita-Cochrane, Cynthia Catherine 01 January 2015 (has links)
Commercial nuclear power utilities are under pressure to effectively recruit and retain licensed reactor operators in light of poor candidate training completion rates and recent candidate failures on the Nuclear Regulatory Commission (NRC) license exam. One candidate failure can cost a utility over $400,000, making the successful licensing of new operators a critical path to operational excellence. This study was designed to discover if the NEO-PI-3, a 5-factor measure of personality, could improve selection in nuclear utilities by identifying personality factors that predict license candidate success. Two large U.S. commercial nuclear power corporations provided potential participant contact information and candidate results on the 2014 NRC exam from their nuclear power units nation-wide. License candidates who participated (n = 75) completed the NEO-PI-3 personality test and results were compared to 3 outcomes on the NRC exam: written exam, simulated operating exam, and overall exam result. Significant correlations were found between several personality factors and both written and operating exam outcomes on the NRC exam. Further, a regression analysis indicated that personality factors, particularly Conscientiousness, predicted simulated operating exam scores. The results of this study may be used to support the use of the NEO-PI-3 to improve operator selection as an addition to the current selection protocol. Positive social change implications from this study include support for the use of a personality measure by utilities to improve their return-on-investment in candidates and by individual candidates to avoid career failures. The results of this study may also positively impact the public by supporting the safe and reliable operation of commercial nuclear power utilities in the United States.
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Strategies to Implement Efficient Closing CyclesScott, Mary Christine 01 January 2019 (has links)
Many financial leaders lack strategies to make the timely fiscal reporting needed for business to obtain profitability, competitive advantage, and sustainability. The purpose of this single case study was to explore successful strategies used to complete efficient closing cycles to evaluate performance and support business decisions. The conceptual framework for this study was process improvement and the theory of constraints. Data were collected from semistructured interviews with 5 purposively selected leaders; data were supplemented with information from the organization's website and print materials. Financial leaders who had developed successful strategies to complete timely financial statements were selected to participate in the study from a U.S. healthcare organization. Data were analyzed using Yin's 5-step approach, which included examining, categorizing, tabulating, creating a data display, and testing the data. Transcript review validated that emerging themes were in alignment with participant experiences. Four major themes emerged from data analysis: provide training and professional development, promote teamwork, engage in effective communication, and use information technology. Social change implications include potential process improvement in hospitals that could provide insight into specific system processes that contribute to the rising cost of global healthcare. Financial leaders achieving increased profitability through process improvement could enable administrators to make financial contributions to their communities, expand to new markets, and create new employment opportunities.
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Creative Performance on the Job: Does Openness to Experience Matter?Pace, Victoria L 04 April 2005 (has links)
Finding what is alike among the personalities of creative people has been a dream of many researchers. No single personality type has been discovered as prototypical, yet the promise of common attributes among creative people remains enticing. This study examines one of these promising characteristics - Openness to Experience, a personality factor from the Five-Factor Model. This factor has been shown to correlate positively with creativity in past studies. In the present study this relationship was partially confirmed in a sample of employees whose jobs require technical problem solving, by correlating the employees self-rated Work-specific Openness to Experience and NEO PI-R Openness with supervisory ratings of their creative work performance. The Work-specific Openness scale demonstrated a significant correlation with supervisory ratings of creativity, whereas the NEO PI-R Openness scale did not. Although none of the NEO PI-R facets were significant predictors of criterion, four Work-specific facets were significant predictors based on zero order correlations. These facets are Openness to Ideas, Fantasy, Values, and Actions. However, although individual facets of Openness were expected to differ in validity, the magnitude of their correlations with creative performance scores did not differ significantly. Convincing results showing incremental validity of the Work-specific scale over the NEO PI-R scale are also discussed.
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Automatisk trimning av drivsystemreglering från MATLABKöhlström, Jonas January 2007 (has links)
<p>This master thesis covers the development of an automatic tuning process for the existing speed controller for drive systems. The drive systems are resonant two-mass systems where a motor is used to drive a load connected by a shaft. The developed method relies heavily on system identification and the construction of a complete mechanical model of the process. With this approach, the common problem with poor load speed control that derives from measuring only the motor speed can be addressed and solved for a majority of such processes.</p><p>The automatic tuning method has along with general test functions been implemented in a complete tool for automatic tuning, testing and performance evaluation and reporting for drive systems.</p>
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Change and stability in the dietary system of a prehistoric coastal population in southern TaiwanLi, Kuangti. January 1997 (has links) (PDF)
Thesis (Ph.D.)--Arizona State University, 1997. / Includes bibliographical references.
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Development of methodology for detection of defect locations in pavement profileRawool, Shubham Shivaji 29 August 2005 (has links)
Pavement smoothness has become a standard measure of pavement quality. Transportation agencies strive to build and maintain smoother pavements. Smooth roads provide comfort while riding, minimize vehicular wear and tear and increase pavement life. A user perceives smoothness of a pavement based on the ride quality, which is severely affected by presence of defects on pavement surface. Defects identified after construction are corrected as per smoothness specifications prescribed by respective transportation agencies. The effectiveness of any method used to determine defect locations depends on the decrease in roughness obtained on correction of defects. Following the above line of thought a method that detects defects by comparing original profile to a smoothened profile will be more effective in identifying defect locations that cause roughness in pavements. This research report proposes a methodology to detect defect locations on pavement surface using profile data collected on pavements. The approach presents a method of obtaining a smoothened profile from the original profile to help identify defect locations based on deviations of the original profile from the smoothened one. Defect areas will have a higher deviation from the smoothened profile as compared to smooth areas. The verification of the defects identified by this approach is carried out by determining the decrease in roughness after removal of the identified defects from profile. A roughness statistic is used to do the same. The approach is illustrated using profile data collected on in-service pavement sections.
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Fluorescent Reagents to Improve the Analytical Infrastructure of Capillary Electrophoretic SeparationsLi, Ming-Chien 2012 May 1900 (has links)
Two types of fluorescent molecules had been designed and synthesized to improve the analytical infrastructure of capillary electrophoretic separations. First, a hydrophilic version of the permanently cationic acridine-based fluorophore, HEG2Me2-DAA was synthesized. HEG2Me2-DAA has a lambda^ex max of 490 nm which matches the 488 nm line of the commonly used argon ion laser. The emission spectra of HEG2Me2-DAA are pH-independent. HEG2Me2-DAA was used in capillary electrophoresis with an aqueous background electrolyte and was found to be free of the detrimental peak tailing of the acridine orange-based fluorophore that was caused by adsorption on the inner wall of the fused silica capillary. Bovine serum albumin was labeled with excess of the designed amine reactive reagent and the lowest concentration at which the tagged bovine serum albumin was tested was 15 nM. Chicken ovalbumin was also labeled with FL-CA-PFP and analyzed by capillary isoelectric focusing (cIEF) with LIF detection. The pI values of the tagged proteins shifted in the alkaline direction by about 0.02 compared to the pI values of the non-tagged proteins. A tri-functional probe intended to enable selective enrichment and selective detection of a variety of molecules (e.g., natural products, pharmaceuticals, inhibitors, etc.) was also designed and synthetized by combining FL-CA with biotin and an azide group in a "proof-of-principle" level experiment.
In cIEF, the profile of the pH gradient can only be determined with the help of pI markers. A large set of pyrene-based fluorescent pI markers was rationally designed to cover the pI range 3 to 10. To prove the feasibility of the proposed synthetic approach, the subgroup of the pI markers having the greatest structural complexity was synthesized and characterized. The classical zone electrophoretic pI determination methods failed due to severe chromatographic retention of the APTS based pI markers on the capillary wall. Exploratory work was done to design a new pI value determination method that combines the advantages of the immobilized pH gradient technology of the OFFGEL instrument and the carrier-ampholyte-based IEF technology. The method aspects of cIEF have also been improved in this work. The new segmented loading method yielded a more linear pH gradient than the previously known cIEF methods. To exploit a unique property of the newly developed fluorescent pI markers, we used them as pyrene-based ampholytic carbohydrate derivatizing reagents. The pI4 carbohydrate derivatization reagent proved advantageous over 8-aminopyrene-1,3,6-trisulfonic acid (APTS): the pI4 conjugates have higher molar absorbance at 488 nm than the APTS conjugates and become detectable in positive ion mode of MS affording better detection sensitivity.
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Human papillomavirus tropism : determinants of viral tissue specificityMistry, Nitesh January 2007 (has links)
Cervical cancer is the second most common cancer among women worldwide and human papillomavirus (HPV) is a prerequisit for the development of this cancer. HPV belongs to the Papillomaviridae family and infects the basal layer of epithelial cells where it generally progresses into warts or condylomas. HPV can only reproduce in differentiating epithelia and it is therefore difficult to study the natural infection of HPV. More than 100 HPV types exist and they are divided into different genera based on their L1 open reading frame sequence. Most of the HPV types in the alpha-papillomavirus genus infect the mucosal epithelium while HPVs from the beta-papillomavirus genus usually infect cutaneous epithelial cells. Presently, it is not known what decides the anatomical tropism and our aim was to study determinants of this tropism. By using HPV virus like particles (VLP) and pseudovirus we found that VLPs from the two alpha-papillomaviruses HPV-6 and HPV-16 interacted with cell-surface heparan sulfate (HS) for initial attachment. When we labelled HPV VLPs with a fluorescent dye to study internalization HPV-6 was more strongly inhibited than HPV-16. Furthermore, a pseudovirus infection assay demonstrated that the beta-papillomavirus HPV-5 was less dependent on HS for infection than HPV-16. By analyzing the isoelectric point (p1) of the HPV L1 capsid protein we found that alpha HPV types were more positively charged than beta HPV types. Also, HPV-6 had a higher positive charge than HPV-16. Thus, the inhibition of the negatively charged heparin against HPV infection was clearly related to the charge of the HPV L1 capsid. This suggested that the initial interaction could be one of the determinants of tropism although not the sole factor. Lactoferrin is a protein found in milk, saliva, semen, tear fluid and endocervical secretions that has antiviral activities. Both human and bovine lactoferrin inhibited HPV infection but we found no significant differences in inhibition of alpha- and beta-papillomavirus infection. We could however demonstrate that different lactoferricins, small peptide derivates from the N-terminal part of lactoferrin, were able to inhibit HPV infection. This antiviral activity depended on lactoferricin peptide, HPV type and cell origin. The regulation of HPV gene expression in the host cell could also determine HPV tropism. The HPV long control region (LCR) contains cis-responsive elements that regulate HPV transcription and the epithelial tropism of HPV is determined by epithelial specific constitutive enhancers in the LCR. It has been hypothesized that the combination of transcription factors in the host cell determines the cell-type-specific expression. In cells with a skin origin the HPV-5 LCR was twice as efficient in transcriptional activation compared to HPV-16 LCR, while in cervical cells the HPV-16 LCR was almost twice as effective in activating transcription compared to HPV-5 LCR. To conclude, alpha- and beta-papillomaviruses differed regarding their ability to infect cells and regulate viral gene expression. These abilities corresponded with their natural host cells and suggested that HPV anatomical tropism could be determined at several steps in the HPV life cycle.
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