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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.
411

The relationship between the Affective Facial Recognition Test and the Facial Recognition Test with a group of left and right CVA patients

Schmidt, Edward E. January 1984 (has links)
The purpose of this study was to investigate the relationship between the Affective Facial Recognition Test (AFRT) and Facial Recognition Test (FRT) with a group of right and left hemisphere CVA patients and controls. In addition, the differences in abilities of right and left hemisphere CVA patients and controls to perform on these two tests was explored. The four null hypotheses were: (a) There will be no significant differences between right and left hemisphere damaged patients and controls on the AFRT, (b) There will be no significant differences between right and left hemisphere damaged patients and controls on the FRT, (c) There will be no significant relationship between the AFRT and FRT with right hemisphere damaged patients, and (d) There will be no significant relationship between the AFRT and FRT with left hemisphere damaged patients. Hypotheses one and two were statistically analyzed by using a One-Way Analysis of Variance and three and four by a Pearson Product Moment Correlation.Experimental group subjects were 16 right and 16 left hemisphere CVA volunteer patients obtained from Community Hospital, Indianapolis, Indiana. The control group was composed of 16 non-neurologically impaired subjects from the Muncie, Indiana area. All subjects were equated with respects to age, education, and post-injury. The subjects were randomly administered the AFRT, FRT, and Comprehension subtest of the WAIS-R. The Comprehension subtest was used as a screening device to insure that the patients understood what was expected of them during the testing. The testing, data analysis, and interpretation was completed between May, 1982 and February, 1984.All four hypotheses were rejected. Right and left hemisphere CVA patients and controls significantly differed in performance on the AFRT and FRT (r<.01). In short, right and left hemisphere CVA's were significantly impaired on the AFRT and FRT when compared with the controls. However, both experimental groups exhibited equal impairment on the two tests. This suggests that neither affective facial recognition nor facial recognition is hemispherically lateralized. Also, a higher relationship (r=.79) was found between the AFRT and FRT with right hemisphere patients as opposed to left (r=.65). This appears to indicate that both tests are measuring similar neurological functions and that the inability to match unfamiliar faces and affective faces may not be two separate disorders.
412

The effects of role playing and coaching on the ability to simulate a traumatic brain injury profile on the Minnesota Multiphasic Personality Inventory-2nd edition (MMPI-2) / MMPI-2 coaching

Bubp, Corby A. January 2004 (has links)
There is no abstract available for this dissertation. / Department of Counseling Psychology and Guidance Services
413

An investigation of knowledge among counselor educators, educators in clinical psychology, and psychiatrists regarding selected aspects of brain damage

Dubnick, Barbara January 1975 (has links)
The purpose of this study was to explore and compare specific areas of knowledge among counselor educators, educators in clinical psychology, and psychiatrists regarding selected aspects of brain damage. Areas explored included knowledge of soft signs, knowledge of pertinent standardized tests and other methods of assessing brain damage, and kinds of referral sources. The specific intention of collecting the data was to provide information which might be useful for the modification and development of curriculum and instructional design in counselor education training programs.The three populations consisted of 20 counselor educators, 20 educators in clinical psychology, and 13 psychiatrists who responded to a letter requesting their participation in a brief telephone interview. A questionnaire consisting of sex questions about brain damage was administered by telephone to the three populations to compare their knowledge regarding selected aspects of brain damage. The questionnaire data were reported by number and percentage for each item.The conclusions drawn from this study included:1. Educators in clinical psychology and psychiatrists suspected brain damage in their clients/patients more frequently than counselor educators. It would appear from this that either there is a higher frequency of suspected brain damage among client/patients seen by clinical psychologists and psychiatrists or that they are more alert to the possibility than counselor educators.2. Educators in clinical psychology appeared to be the most knowledgeable of the three groups with respect to soft signs of brain damage. Counselor educators mentioned the least number of soft signs.3. Educators in clinical psychology mentioned more standardized psychological tests used for diagnosing brain damage than the other two groups. Counselor educators were the least familiar with these tests.4. Psychiatrists were more familiar with the medical laboratory tests used for diagnosing brain damage than the other two groups. Counselor educators knew the least in this area.5. The majority of respondents in all three groups were either not aware of non-standardized techniques used for investigating possible brain damage, or they preferred not to use them.6. All of the psychiatrists and most of the counselor educators and educators in clinical psychology have referred clients/patients for further diagnosis when they suspected brain damage. The referral sources most frequently mentioned by all three groups were neurologists, neurosurgeons, psychologists, physicians, or hospitals or medical centers.
414

Evaluation of stress induced damage in composite material

Priston, Ann-Marie January 1997 (has links)
No description available.
415

Role of Base and nucleotide excision repair pathways in processing of clustered DNA lesions induced by ionising radiation

Budworth, Helen Louise January 2003 (has links)
Ionising radiation (IR) induces a wide spectrum of lesions in DNA, including double- and single-strand breaks, abasic (AP) sites and a variety of base lesions. IR-induced damage to DNA can range from simple, isolated lesions to clustered DNA damage in which multiple lesions are formed, usually within a single helical turn of the DNA. Individual lesions within a cluster are recognised by repair enzymes of the base excision repair (BER) pathway, however, clustered DNA damage may be recognised as a bulky lesion and be processed by nucleotide excision repair (NER). Additionally, the presence of other closely spaced lesions may affect the rate and fidelity of DNA repair and, in doing so, may contribute to the harmful effects of ionising radiation. The aim of this study is to gain further understanding of the repairability of clustered DNA damage and the effects of multiple lesions on cellular repair systems. 7, 8-dihydro-8-oxoguanine (8-oxoG), thymine glycol (Tg), AP sites and single-strand breaks (SSB), some of the most frequently formed IR-induced DNA lesions, were employed in synthetic oligonucleotides to model various types of clustered lesions and their repairability was studied using purified base excision repair enzymes and cell extracts. It was revealed that BER is the major repair system involved in the processing of clustered DNA lesions, and that some clustered lesions are repaired with decreased efficiency. Both the composition of lesions in a cluster and the positioning of the various lesions determine their repairability by base excision repair enzymes.
416

The role of RAD51-like genes in the repair of DNA damage in mammalian cells

French, Catherine A. January 2003 (has links)
No description available.
417

Development of the random amplified polymorphic DNA (RAPD) technique to measure the effects of genotoxinsin aquatic organisms

Atienzar, Franck Andre January 2000 (has links)
Studies were undertaken to evaluate the potential of random amplified polymorphic DNA (RAPD) to detect DNA effects (including DNA damage and mutations) in aquatic invertebrates, following their exposure to a variety of environmental contaminants under laboratory conditions. After rigorous optimisation of the RAPD method, the protocol, which used a high annealing temperature (50&quot;C for 10-mer primers), was found to generate good-quality DNA profiles from groups of organisms belonging to the bacterial, plant and animal kingdoms. The RAPD method was initially used to detect benzo(a)pyrene [B(a)P] and copper-induced DNA effects in the water flea Daphnia magna and ultraviolet-mediated DNA effects in the marine alga Palmaria palmata. The results clearly showed that changes occurred in RAPD profiles obtained from the exposed populations when compared to controls. In these studies, the effect of the genotoxins at higher levels of biological organisation (e.g. Darwinian parameters and/or fitness parameters) were also investigated and were compared with genomic DNA template stability (GTS), a qualitative index representing clear changes in panems compared to control RAPD profiles. The results from these experiments revealed that GTS could be more sensitive than growth parameters and showed at least equal or even greater sensitivity than other measures of fitness. Changes in RAPD profiles were believed to be the result of DNA effects, namely adduct formation, DNA breakage, oxidative damage and mutations and possibly other effects (e.g. variation in gene expression). Nevertheless, the nature and amount of DNA effects could only be speculated because diverse events may induce the same category of changes (i.e. variation in band intensity, appearance of bands, and disappearance of amplicons) in RAPD patterns. Further studies confirmed that RAPD had the potential to qualitatively detect oestrogen and xeno-oestrogen -induced DNA effects in barnacles. Additional experiments emphasised that oxygen radicals and variation in gene expression may induce significant changes in RAPD profiles. To further understand the effects of DNA lesions and mutations on RAPD patterns, individual types of DNA damage were created in vitro. The results clearly indicated that BaP DNA adducts, DNA photoproducts. and DNA breakages had significant effects on RAPD profiles but that diverse types of DNA damage may induce the same category of changes in RAPD patterns which render the interpretation of the results difficult. It was also concluded that mutations could be detected provided they do not arise in a random fashion. Finally, an attempt was made to determine the kinetics of DNA damage and DNA repair and whether changes in patterns obtained from B(a)P exposed Daphnia magna could be transmitted to successive generations. This strategy was developed to distinguish between mutations and DNA damage. The results showed that some bands obtained from the exposed populations were transmitted to the first and/or second generation but not to the third. It was concluded that the transmission of modified genetic material to the offspring was more likely to be the result of large genomic rearrangements and/or base methylation (epigenetic processes) rather than point mutations. In conclusion, the results presented in this research project show the potential of the RAPD assay as a useful method for the qualitative assessment of DNA effects including genotoxicity and changes in gene expression. The main advantage of this technique is that it can be applied to any species without requiring any information about the nucleotide sequence. In the field of ecogenotoxicology, its main advantage lies in its sensitivity and speed to detect a wide range of DNA damage including DNA breakage, DNA adducts, oxidative damage as well as mutations (including point mutations and large rearrangements). On the other hand, RAPD only allows a qualitative assessment of the DNA effects and the nature of the changes occurring in profiles can only be speculated. Finally, a great deal of further experimentation and validation are required in order to assess the applicability of the technique to a variety of other species and pollutants, particularly under field conditions.
418

Analysis of Rad3 and Chk1 checkpoint protein kinases

Martinho, Rui Goncalo V. R. C. January 1999 (has links)
No description available.
419

Development of a knowledge-based system for the repair and maintenance of concrete structures

Moodi, Faramarz January 2001 (has links)
Information Technology (IT) can exploit strategic opportunities for new ways of facilitating information and data exchange and the exchange of expert and specialist opinions in any field of engineering. Knowledge-Based Systems are sophisticated computer programs which store expert knowledge on specific subject and are applied to a broad range of engineering problems. Integrated Database applications have facilitated the essential capability of storing data to overcome an increasing information malaise. Integrating these areas of Information Technology (IT) can be used to bring a group of experts in any field of engineering closer together by allowing them to communicate and exchange information and opinions. The central feature of this research study is the integration of these hitherto separate areas of Information Technology (IT). In this thesis an adaptable Graphic User Interface Centred application comprising a Knowledge-Based Expert System (DEMARECEXPERT), a Database Management System (REPCON) and Evaluation program (ECON) alongside visualisation technologies is developed to produce an innovative platform which will facilitate and encourage the development of knowledge in concrete repair. Diagnosis, Evaluation, MAintenance and REpair of Concrete structures (DEMAREC) is a flexible application which can be used in four modes of Education, Diagnostic, Evaluation and Evolution. In the educational mode an inexperienced user can develop a better understanding of the repair of concrete technology by navigating through a database of textual and pictorial data. In the diagnostic mode, pictures and descriptive information taken from the database and performance of the expert system (DEMAREC-EXPERT) are used in a way that makes problem solving and decision making easier. The DEMAREC-EXPERT system is coupled to the REPCON (as an independent database) in order to provide the user with recommendations related to the best course required for maintenance and in the selection of materials and methods for the repair of concrete. In the evaluation mode the conditions observed are described in unambiguous terms that can be used by the user to be able to take engineering and management actions for the repair and maintenance of the structure. In the evolution mode of the application, the nature of distress, repair and maintenance of concrete structures within the extent of the database management system has been assessedT. he new methodology of data/usere valuation could have wider implications in many knowledge rich areas of expertise. The benefit of using REPCON lies in the enhanced levels of confidence which can be attributed to the data and to contribution of that data. Effectively, REPCON is designed to model a true evolution of a field of expertise but allows that expertise to move on in faster and more structured manner. This research has wider implications than within the realm of concrete repair. The methodology described in this thesis is developed to provide tecýnology transfer of information from experts, specialists to other practitioners and vice versa and it provides a common forum for communication and exchange information between them. Indeed, one of the strengths of the system is the way in which it allows the promotion and relegation of knowledge according to the opinion of users of different levels of ability from expert to novice. It creates a flexible environment in which an inexperienced user can develop his knowledge in maintenance and concrete repair structures. It is explained how an expert and a specialist can contribute his experience and knowledge towards improving and evolving the problem solving capability of the application.
420

Toward Understanding Dynamic Annealing Processes in Irradiated Ceramics

Myers, Michael 03 October 2013 (has links)
High energy particle irradiation inevitably generates defects in solids in the form of collision cascades. The ballistic formation and thermalization of cascades occur rapidly and are believed to be reasonably well understood. However, knowledge of the evolution of defects after damage cascade thermalization, referred to as dynamic annealing, is quite limited. Unraveling the mechanisms associated with dynamic annealing is crucial since such processes play an important role in the formation of stable post-irradiation disorder in ion-beam-processed semiconductors and determines the “radiation tolerance” of many nuclear materials. The purpose of this dissertation is to further our understanding of the processes involved in dynamic annealing. In order to achieve this, two main tasks are undertaken. First, the effects of dynamic annealing are investigated in ZnO, a technologically relevant material that exhibits very high dynamic defect annealing at room temperature. Such high dynamic annealing leads to unusual defect accumulation in heavy ion bombarded ZnO. Through this work, the puzzling features that were observed more than a decade ago in ion-channeling spectra have finally been explained. We show that the presence of a polar surface substantially alters damage accumulation. Non-polar surface terminations of ZnO are shown to exhibit enhanced dynamic annealing compared to polar surface terminated ZnO. Additionally, we demonstrate one method to reduce radiation damage in polar surface terminated ZnO by means of a surface modification. These results advance our efforts in the long-sought-after goal of understanding complex radiation damage processes in ceramics. Second, a pulsed-ion-beam method is developed and demonstrated in the case of Si as a prototypical non-metallic target. Such a method is shown to be a novel experimental technique for direct extraction of dynamic annealing parameters. The relaxation times and effective diffusion lengths of mobile defects during the dynamic annealing process play a vital role in damage accumulation. We demonstrate that these parameters dominate the formation of stable post-irradiation disorder. In Si, a defect lifetime of ∼ 6 ms and a characteristic defect diffusion length of ∼ 30 nm are measured. These results should nucleate future pulsed-beam studies of dynamic defect interaction processes in technologically relevant materials. In particular, understanding length- and time-scales of defect interactions are essential for extending laboratory findings to nuclear material lifetimes and to the time-scales of geological storage of nuclear waste.

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