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Proton-Induced L-shell X-Rays of Pr, Sm, Eu, Gd, and Dy

Description: Characteristic L-shell x rays of the five rare earths Pr, Sm, Eu, Gd, and Dy were studied in this work. The x rays were produced by ionization from 0.3 to 2.0 MeV protons from the 2.0 MV Van de Graaff at North Texas State University. Total L-shell ionization and x-ray production cross sections were measured for Sm and compared to the BEA, CBEA and PWBA theories. Total L-shell ionization cross sections were measured for Pr, Eu, Gd, and Dy and compared to the BEA, CBEA, and PWBA. The CBEA and PWBA fit the samarium data well for both ionization and x-ray production cross sections. The BEA was generally 40 per cent lower than the data. The CBEA and the PWBA also fit the ionization cross section data for Pr, Eu, Gd and Dy, while the BEA was generally 40 per cent lower than the data.
Date: August 1974
Creator: Abrath, Frederick G.

Diphenyloxazole Metabolism by Aryl Hydrocarbon Hydroxylase

Description: 2,5-Diphenyloxazole (PPO) was tested as a potential alternate inducer for the aryl hydrocarbon hydroxylase (AHH) system. Its apparent lack. of carcinogenicity and toxicity provide a possible system for investigation of enzyme systems related to chemical carcinogenesis without exposure of the researcher to potent carcinogenic compounds. These studies found PPO to be an inducer of AHH in cultured human lymphocytes. When PPO was utilized as a substrate for the AHH assay system, the major metabolites produced were strongly fluorescent. A simple fluorometric assay was developed which employed PPO as the substrate and which measured constitutive activity more efficiently than similar assays using benzo(a)pyrene as the substrate. Quantitation of both basal and induced lymphocyte AHH metabolism of PPO may be applicable to human population studies and may provide a tool to determine possible genetic variables with respect to carcinogen metabolism related to cancer risk.
Date: December 1976
Creator: Abreu, Mary E.

Ultrafast Laser Sampling of a Plant Tissue and ion Conductivity Measurement for Investigation of Light Stress Generation Mechanisms

Description: In this study we applied ultra-short laser pulses on a biological sample (Arabidopsis), in order to cut it precisely in a square pattern and subsequently use it for studying stress generation mechanisms. For this purpose, we utilized femtosecond laser pulses at 100 fs pulse width and 80 MHz repetition rate. We took two processing parameters into consideration such as laser power, laser exposure time which is related to the stage speed. Therefore, we were able to find the laser optimum conditions for ablation of biological tissues. The mutant and wildtype (control) obtained from laser cutting with a size of 500 µm × 500 µm were directly transferred (in-situ with laser cutting) into a microfabricated chamber containing ~500 nanoliters deionized water for measuring ion conductivity. The ion conductivity is a signature of cell-death mechanisms caused by various stresses. A light with intensity of 100 µmol was exposed to the samples for 2 hours and 20 minutes as a source of stress. A quantitative electrical analysis with high accuracy was assured by utilizing a microchamber, which enables a measurement in nanoliter volume. We measured the impedance which is reciprocal of conductivity using a lock-in amplifier and a precise current source at frequency of 130 Hz. Initially high impedance of mutant sample tended to drop within 2 hours and finally approached the constant value which signified that the cell death mechanism was complete. However, the wildtype sample demonstrated approximately constant impedance (conductivity) during the experiment.
Date: August 2010
Creator: Abtahi, Seyed Ali

Application of Synthetic Peptides as Substrates for Reversible Phosphorylation

Description: Two highly homologous synthetic peptides MLC(3-13) (K-R-A-K-A-K-T-TK-K-R-G) and MLC(5-13) (A-K-A-K-T-T-K-K-R-G) corresponding to the amino terminal amino acid sequence of smooth muscle myosin light chain were utilized as substrates for protein kinase C purified from murine lymphosarcoma tumors to determine the role of the primary amino acid sequence of protein kinase C substrates in defining the lipid (phosphatidyl serine and diacylglycerol) requirements for the activation of the enzyme. Removal of the basic residues lysine and arginine from the amino terminus of MLC(3-13) did not have a significant effect on the Ka value of diacylglycerol. The binding of effector to calcium-protein kinase C appears to be random since binding of one effector did not block the binding of the other.
Date: August 1992
Creator: Abukhalaf, Imad Kazem

Corporate Christians and Terrible Turks: Economics, Aesthetics, and the Representation of Empire in the Early British Travel Narrative, 1630 - 1780

Description: This dissertation examines the evolution of the early English travel narrative as it relates to the development and application of mercantilist economic practices, theories of aesthetic representation, and discourses of gender and narrative authority. I attempt to redress an imbalance in critical work on pre-colonialism and colonialism, which has tended to focus either on the Renaissance, as exemplified by the works of critics such as Stephen Greenblatt and John Gillies, or on the later eighteenth and early nineteenth centuries, as in the work of scholars such as Srinivas Aravamudan and Edward Said. This critical gap has left early travel narratives by Sir Francis Moore, Jonathan Harris, Penelope Aubin, and others largely neglected. These early writers, I argue, adapted the conventions of the travel narrative while relying on the authority of contemporary commercial practices. The early English travelers modified contemporary conventions of aesthetic representation by formulating their descriptions of non-European cultures in terms of the economic and political conventions and rivalries of the early eighteenth century. Early English travel literature, I demonstrate, functioned as a politically motivated medium that served both as a marker of authenticity, justifying the colonial and imperial ventures that would flourish in the nineteenth century, and as a forum for experimentation with English notions of gender and narrative authority.
Date: December 2003
Creator: Abunasser, Rima Jamil

Exploratory Analysis of Social E-health Behavior

Description: Extant literature has documented well that people seek health information via the internet as patients and consumers. Much less, however, is known about interaction and creation behaviors in the development of new online health information and knowledge. More specifically, generalizable sociodemographic data on who engages in this online health behavior via social media is lacking in the sociological literature. The term “social e-health” is introduced to emphasize the difference between seeking behaviors and interaction and creation behaviors. A 2010 dataset of a large nationally representative and randomly sampled telephone survey made freely available from the Pew Research Center is used to examine social e-health behavior according to respondents’ sociodemographics. The dependent variable of social e-health behavior is measured by 13 survey questions from the survey. Gender, race, ethnicity, age, education, and income are used as independent variables. Logistic regression analysis was used to determine the odds of engagement in social e-health behavior based on the sociodemographic predictors. The social determinants of health and digital divide frameworks are used to help explain why socioeconomic variances exist in social e-health behavior. The findings of the current study suggest that predictable sociodemographic patterns along the dimensions of gender, race, age, education, and income exist for those who report engaging in social e-health behavior. This study is important because it underscores the fact that engagement in social e-health behavior is differentially distributed in the general U.S. population according to patterned sociodemographics.
Date: May 2014
Creator: Acadia, Spencer

Cooperative Strategy and Sources of Knowledge Integration Capability and Innovation: A Relational View

Description: Faced with the challenges to addressing the novelties of the changing business environments (e.g., new customer requirement, changes in customers taste and preferences, the introduction of new products or services by competitors), organizations seek to build collaboration among their employees who possess complementary knowledge. Integrating complementary knowledge enhances employees' ability to address environmental challenges and foster innovation. Despite the importance of knowledge integration for innovation, integration of such knowledge becomes difficult when employees lack a shared understanding of knowledge, and when the knowledge is newly generated. Because new knowledge is tacit in nature and highly personal to a particular individual, it is difficult to articulate, making knowledge integration (KI) an arduous task. Lack of shared understanding, the presence of new knowledge, and lack of common interests in employees creates three types of knowledge boundaries – syntactic (information processing) boundaries, semantic (interpretive) boundaries, and pragmatic (political) boundaries. The presence of knowledge boundaries makes it difficult for employees to share and access their knowledge with each other. To overcome the challenges related to the knowledge boundaries, employees use boundary-spanning objects, which are common lexicons, common meaning, and common interests, to share and access their knowledge across the boundaries. Although prior studies have emphasized the importance of knowledge integration of various knowledge sources for innovations, examinations of what enhances KI capability of employees for organizational innovation remain limited. In addition, apart from Carlile, (2004) and Franco (2013), which are both case studies, other studies that examine the role of boundary spanning objects for knowledge integration are missing. The knowledge management literature also fails to measures (the success of common lexicons, common meaning, and common interests for achieving KI capability) boundary spanning objects. Therefore, in this study, new measurement items of boundary spanning objects and novelty are developed to test the hypotheses. A survey-based ...
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Date: August 2016
Creator: Acharya, Chandan

The Meaning of Elder Abuse

Description: Elder abuse first received national attention in 1980, as the subject of a congressional investigation. Now, 20 years later, establishing successful strategies of identification, subsequent intervention, and prevention of abuse is of paramount importance; but progress toward this goal is hindered by lack of consensus as to the definition of elder abuse, and the use of vague, confusing, and sometimes contradictory terms in its discussion. In this paper, both social research and professional approaches and legal approaches to the definition of elder abuse are surveyed, as are definitions formulated for the National Elder Abuse Incidence Study conducted by the National Center on Elder Abuse. The continuing need for a universal or standard definition is emphasized.
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Date: May 2000
Creator: Achilli, Raye

Love Attitudes and Marital Adjustment Through Five Stages of the Marital Life-Cycle in Protestant Nigerian Society

Description: This study examined the relationship between love attitude and marital adjustment across five stages of the marital life-cycle in Nigerian society. The subjects for this study were 202 volunteers from six protestant churches representing six cities in the southern part of Nigeria. An average of 20 couples were representatives of each of the five marital life-cycles. Each of the subjects completed the Love Attitude Inventory (LAI), and the Marital Adjustment Test (short form) (MAT). Wilk's multivariate analysis revealed no significant differences between husbands' and wives' love attitude and marital adjustment across the five stages of the marital life cycle. Multivariate analysis split-plot 5.2 with repeated measures revealed no significant difference for the total sample among the groups, but indicated a significant difference between love attitude and marital adjustment for the total sample using sex as a factor. A univariate test of the MAT and LAI indicated that the MAT accounted for the difference. A canonical correlation indicated a significant positive relationship between husbands1 and wives' marital adjustment and love attitude within each of the five groups. The findings suggest that husbands and wives included in this study have a good understanding of their roles in the marriage relationship and that the partners have general agreement regarding those roles. The marriage partners apparently have strong influences on each other's perceptions of love attitude and marital adjustment.
Date: December 1988
Creator: Acho, Onyebuchi S. (Onyebuchi Sunday)

Haves, Halves, and Have-Nots: School Libraries and Student Achievement in California

Description: This descriptive, non-experimental study examines the strength of the relationship between California school library media programs and student achievement, using data from California criterion-referenced state-wide tests, publically available school and community demographic data, and a state survey of school library programs. Results indicate a substantial discrepancy in library staffing levels from the elementary grades through the high schools. Nevertheless, statistically significant correlations were found between certificated staffing levels and student achievement at each grade. Significant correlations persisted at the elementary and middle school when controlling for five of six school and community variables, and at the high school when controlling for all six of those variables. Bivariate correlations between total staffing and student achievement were significant at both the middle school and high school level when controlling for all school and community variables. Generally, the strength of the correlations between both certificated and total staffing tended to increase with grade level; at the high school level, correlations were among the strongest reported in any statewide study to date. There was a significant positive relationship between a majority of the 21 library services regularly provided and student achievement at all levels. Total library services were significantly related to student achievement at all levels when controlling for all school and community variables. In multiple regression analyses, there was an increasingly stronger relationship between total library programs and student achievement by grade level when controlling for all school and community variables. At every level, certificated and total staffing levels were associated with the strength of library program elements. The findings from this study confirm a host of prior research on the relationship between school libraries and student achievement and point to inequitable access to school library services in California. Results from this study might also provide a baseline of data for qualitative research ...
Date: December 2008
Creator: Achterman, Douglas L.

A Study to Determine the Relationship of Versatile Behavior to Individual Demographics, Job Characteristics, Organizational Climate Performance Feedback and Job Satisfaction

Description: The behavioral characteristics of leaders have been subjects of study for centuries. The scope of these studies has grown to encompass task analysis, follower needs and situational requirements. Current leadership theories consistently recognize the need for a successful leader to adjust behavior to meet the needs of the task, followers and situation. The problem of this research is to define this ability to modify one's behavior, measure it and test its relationship to demographic and job characteristics. The purpose of this study is to evaluate the correlation of individuals" ability to modify their behavior to job function, hierarchy, climate, feedback, satisfaction and their demographic characteristics. The hypotheses held that high ability to modify behavior would correlate positively with job characteristics, climate, feedback and satisfaction and show no correlation to individual demographics. Data were collected through the administration of three research instruments to 138 managers of three business firms. The instruments were the Participant Data Form providing job and demographic characteristics, Descriptive Adjective Questionnaire measuring an individual ability to modify behavior, and Climate and Satisfaction Evaluation Index measuring climate, feedback and satisfaction. Perason's correlation coefficients were calculated to identify possible relationship between the manager's ability to modify behavior, called versatility, and all other independent variables, and linear and multiple regressions were utilized to verify the relationship. No significant statistical correlation was found. Conclusions are that the ability of a manager to vary behavior does not influence job climate, feedback or satisfaction, that the versatile behavior is not derived from job or demographic characteristics, and that job satisfaction is directly and positively related to performance feedback and climate.
Date: May 1988
Creator: Ackerman, Raymond L. (Ramond Lorens)

DNA-DNA Hybridization of Methane Oxidizing Bacteria

Description: Bacteria classified in the family Methylomonadaceae must derive their carbon from one-carbon compounds. They are characterized by the possession of internal membranes of two types. Type I membranes are layered and fill the middle of the cells while type II membranes form concentric layers around the periphery of the cells. Also, there are two metabolic pathways by which the methylobacteria assimilate one-carbon compounds. Further evidence of this dichotomy was sought by DNA-DNA saturation hybridization of DNAs from both types of methylobacteria. Very low DNA-DNA homology was seen between types I and II or within the types. It was not possible, therefore, to correlate the degree of genetic relatedness with either the nature of the internal membranes or the pathway of carbon assimilation.
Date: December 1976
Creator: Ackerson, Jill W.

Megadrought and Megadeath in 16th Century Mexico

Description: The native population collapse in 16th century Mexico was a demographic catastrophe with one of the highest death rates in history. Recently developed tree-ring evidence has allowed the levels of precipitation to be reconstructed for north central Mexico, adding to the growing body of epidemiologic evidence and indicating that the 1545 and 1576 epidemics of cocoliztli (Nahuatl for "pest") were indigenous hemorrhagic fevers transmitted by rodent hosts and aggravated by extreme drought conditions.
Date: 2002
Creator: Acuna-Soto, Rodolfo; Stahle, David W.; Cleaveland, Malcolm K. & Therrell, Matthew D.
Item Type: Text

The Value of Filmstrips in the Third Grade

Description: The purpose of this study is to determine the possible influence of the use of filmstrip material upon a group of third-grade pupils as compared with another group of third-grade pupils not using filmstrip materials.
Date: 1950
Creator: Adair, Elva Gaynelle

A Working Bibliography on the Art of Drawing

Description: This working bibliography of 835 publications on the art of drawing is presented in five categories: Educational and Psychological, Historical, "How-to," Technical, and Techniques of Teaching Drawing. The latter category is annotated, offering a synthesis of the areas of art education and drawing. This bibliography is designed for scholars, artists, and teachers as well as students of the many facets of drawing.
Date: August 1974
Creator: Adair, Rosalind Emily

Vibrational Spectra and Potential Function of Tetrachlorocyclopropene

Description: The laser Raman spectra of tetrachlorocyclopropene in the liquid and solid phases have been recorded and vibrational assignments are presented. These results along with root mean squared vibrational amplitudes from electron diffraction data have been employed in a normal coordinate analysis in which a 19 parameter potential function is refined. This potential function, originally expressed in terms of compliance constants, is then used to derive the corresponding conventional and relaxed force constants.
Date: August 1981
Creator: Adame, I. Ernesto (Ignacio Ernesto)

Joint Schemes for Physical Layer Security and Error Correction

Description: The major challenges facing resource constraint wireless devices are error resilience, security and speed. Three joint schemes are presented in this research which could be broadly divided into error correction based and cipher based. The error correction based ciphers take advantage of the properties of LDPC codes and Nordstrom Robinson code. A cipher-based cryptosystem is also presented in this research. The complexity of this scheme is reduced compared to conventional schemes. The securities of the ciphers are analyzed against known-plaintext and chosen-plaintext attacks and are found to be secure. Randomization test was also conducted on these schemes and the results are presented. For the proof of concept, the schemes were implemented in software and hardware and these shows a reduction in hardware usage compared to conventional schemes. As a result, joint schemes for error correction and security provide security to the physical layer of wireless communication systems, a layer in the protocol stack where currently little or no security is implemented. In this physical layer security approach, the properties of powerful error correcting codes are exploited to deliver reliability to the intended parties, high security against eavesdroppers and efficiency in communication system. The notion of a highly secure and reliable physical layer has the potential to significantly change how communication system designers and users think of the physical layer since the error control codes employed in this work will have the dual roles of both reliability and security.
Date: August 2011
Creator: Adamo, Oluwayomi Bamidele

VLSI Architecture and FPGA Prototyping of a Secure Digital Camera for Biometric Application

Description: This thesis presents a secure digital camera (SDC) that inserts biometric data into images found in forms of identification such as the newly proposed electronic passport. However, putting biometric data in passports makes the data vulnerable for theft, causing privacy related issues. An effective solution to combating unauthorized access such as skimming (obtaining data from the passport's owner who did not willingly submit the data) or eavesdropping (intercepting information as it moves from the chip to the reader) could be judicious use of watermarking and encryption at the source end of the biometric process in hardware like digital camera or scanners etc. To address such issues, a novel approach and its architecture in the framework of a digital camera, conceptualized as an SDC is presented. The SDC inserts biometric data into passport image with the aid of watermarking and encryption processes. The VLSI (very large scale integration) architecture of the functional units of the SDC such as watermarking and encryption unit is presented. The result of the hardware implementation of Rijndael advanced encryption standard (AES) and a discrete cosine transform (DCT) based visible and invisible watermarking algorithm is presented. The prototype chip can carry out simultaneous encryption and watermarking, which to our knowledge is the first of its kind. The encryption unit has a throughput of 500 Mbit/s and the visible and invisible watermarking unit has a max frequency of 96.31 MHz and 256 MHz respectively.
Date: August 2006
Creator: Adamo, Oluwayomi Bamidele