VictorJuiz/thesis huggingface dataset:
Aqueous H¦2SO¦4-Al¦2(SO¦4)¦3-MgSO¦4 solutions at 250°C, identification of chemistry and thermodynamics, and application to the pressure acid leaching of laterites

A new chemical model for laterite leach solutions ('ie.,' solutions produced in an autoclave during pressure acid leaching of laterites for nickel extraction) is introduced. The major electrolytes in these solutions are H2SO4, Al2(SO4)3, and MgSO4. A hybrid ion-association-interaction approach is implemented to describe the chemistry and thermodynamics of these ternary solutions at 250°C. The complexes in the solution and the ion-interaction parameters (in the Pitzer model) are identified through processing solubility data in the binary, H2SO4-Al2(SO4) 3 and H2SO4-MgSO4, as well as the ternary, H2SO4-Al2(SO4)3-MgSO 4, electrolyte solutions at or near 250°C. The identified aluminum-bearing species are Al3+, Al(SO4)+, and Al 2(SO4)30, with Al2(SO 4)30 as the dominant species at moderate to high H2SO4 concentrations. Also, Mg2+ and MgSO40 are the identified magnesium-bearing species, with Mg2+ being dominant, except at low concentrations of H2SO4. To verify the identified chemistry of H 2SO4-Al2(SO4)3 solutions independently, the electrical conductivities of these solutions at 250°C, measured through a novel conductivity cell and set-up, are analyzed. These measurements show that the conductivity at constant H2SO4 molality drops with increasing Al2(SO4) 3 molality. This behavior is caused through a decrease in H+ molality and an increase in ionic strength. Furthermore, the slope of the conductivity 'vs.' Al2(SO4) 3 molality is much steeper at low Al2(SO4) 3 molalities than at higher values. This is attributed to a much higher dissociation of Al2(SO4)3 at low molalities than at high values. After this confirmation of the solution chemistry, a typical laterite leach solution is simplified to a ternary electrolyte solution that contains H2SO4, Al2(SO4) 3, and pseudo-MgSO4 ('i.e.,' a lumped entity containing all divalent metal sulfates and having the properties of MgSO 4). A chemical model for these solutions at 250°C is developed (based on the ion-association-interaction approach) and then verified against the measured solubility of aluminum in real leach solutions. It is found that a higher concentration of H2SO4 when processing high-Mg ores is required than that when processing low-Mg ores. This is due to the requirement to maintain the same level of true acidity ('i.e.,' H+ molality rather than H2SO4 molality) "at temperature" in order to obtain comparable Ni extraction rates. Finally, based on the true acidity "at temperature", a new general rate equation for nickel extraction is also developed.
The funerary sacrifice of animals during the predynastic period

Two principal categories of animal burial have been identified for the predynastic period, those animals buried in human graves and those buried independently within the confines of human cemeteries. This study is an attempt to marshal all the available contextual evidence for the independent animal burials, with the intention of providing a cultural framework within which interpretations for such burials may be adequately evaluated. Explanations for the independent animal burials may be formulated within two distinct interpretive frameworks. One assumes a religiously symbolic significance for the species that occur. The other assumes the burials were an aspect of mortuary practices and suggests the possibility of differing species-specific intent for the burials. A review of the archaeological evidence for the two categories of animal burial reveals that the distribution of each conforms to the geographically circumscribed territories of the contemporary, but culturally diverse, cultures of the predynastic period. The available evidence also suggests that the phenomenon of independent animal burial vanished from the cemeteries of the Nile valley north of the Second Cataract with the demise of the Badarian, Maadi (variant), and A-Group as discrete archaeologically detectable cultures. The results of an intersite comparison of the animal and human burials as well as of an investigation of the iconography of each of the cultures with which the independent burials were associated reveal no unequivocal evidence in support of an interpretation of such burials as concrete manifestations of a contemporary attitude of reverence for the animals that occur, either individually or as representatives of their species. In conjunction with the geographically circumscribed and apparently culture-specific distribution of the phenomenon of animal burial, this lack of evidence for reverence for the relevant species suggests that the independent burials, like those in human graves, should be viewed within the context of the traditional burial customs of each of the cultures with which they were associated.
Validity and efficiency of parameter estimates in frequency matched case-control studies

The purpose of this thesis was to examine the effects of a matched design on the validity and efficiency of parameter estimates attained from a case-control study. As well, the use of one control group as a comparison group for two case groups with different confounding distributions was considered. A simulation study was used to compare the estimated disease-exposure association from a matched and unmatched case-control study to the true association. This was performed for populations consisting of different disease, exposure and confounding relationships. With respect to validity, it was shown that regardless of the control sampling method chosen for the case-control study, it was necessary to control for the confounding variable in the analysis. Furthermore it was shown that matching on a non-confounding variable could actually be detrimental if not adjusted for. Efficiency of the parameter estimates was examined under different control sampling methods (asymptotic relative efficiency). In the presence of a confounding variable, in most instances, an increase in the association between the exposure and confounding variable led to a decrease in the amount by which matching was more efficient than random sampling. However, an increase in the association between the confounding variable and the disease led to an increase in efficiency. A data analysis considering the involvement of certain dietary factors in the etiology of prostate and testicular cancer was considered. Again, it was shown that matching on a confounding variable alone did not control for confounding and that adjustment in the analysis was required to attain unbiased estimates describing the association between diet and the two diseases.
Gender differences in health care utilization by the elderly with musculoskeletal disorders

This study examined the association between gender and self-reported utilization of health care services including visits to a general practitioner, specialist, therapist, or chiropractor and use of prescription medications and non-prescription painkillers. Health care service use was for troublesome joints in those aged 55+, living in East York, who responded to a mail/telephone survey (n = 14,244). Of these, 32.15% identified themselves as suffering from joint problems. Females (36%) were significantly more likely to experience extended joint pain than males (27%). [chi]2(1, N = 14,244) = 117.99, p = 0.0000. After adjusting for age and need characteristics, women were just as likely as men to make visits to a general practitioner, chiropractor, therapist and to use prescription medications. However, women were more likely than men to use non-prescription painkillers while men who have osteoporosis were more likely than women with osteoporosis to visit a specialist at least once.
Croatian diaspora almanacs, a historical and cultural analysis

The connection of genre to social processes is considered through the lens of printed almanacs issued in North America in the late nineteenth and twentieth centuries by the diaspora Croatians. The role of genre in sustaining cultural interactions in that community through communication of memories and meanings of identity is interpreted through multidimensional nature of almanac literacy. The almanacs were analyzed as verbal forms, objects that circulate texts, and texts that produce meaning. This analysis has shown how culture is mediated through the almanac genre's structural elements and the symbolic associations derived from its historical roles. Because genres are not only texts but sets of social, political, and economic interactions among the individuals and groups with which they are associated, the ways in which the almanac trade was organized reflects patterns of socialization of communities and individuals, and their ability to mobilize economic, social, and cultural resources in their production. The corpus of 425 almanacs is analyzed using the methods of textual criticism, book history, and cultural analysis, showing how texts can become an informal writing space in which communities outside the dominant culture could interact, and a written arena for oral production. Diaspora almanacs convey a sense of the marginal spaces in which they were produced, distributed, and used. This is noted in particular in the ambiguous position that the printed almanac held in relation to genres of oral communication. Reliance on visual interfaces in structuring information (pictograms, layout, typography, and the use of image) made these materials accessible to individuals at different levels of reading competence. The analysis has shown that such rhetorical simulation of orality is not functional, but serves to forge identity according to the rules of oral memory adapted for the visual interfaces of print medium. Listing and ordering to lay out information schematically, exemplifies how descriptive styles in presenting information are converted into evaluative narratives which convey ideological arguments. Apart from identifying the characteristics of ordering and transmission of social memory in print medium, this study also points to the connection of literacy and power in shaping the culture of the diaspora Croatians.
Forgotten reality, remembered fiction, production values and court opera, 1598-1608

The purpose of this thesis is to construct hypothetical productions of early operas by combining elements taken from documentation of performance practice at the time when the operas were created and fragmentary evidence of actual productions. To this end, I discuss the following operas: ' La Dafne' by Jacopo Peri and Jacopo Corsi, with a libretto by Ottavio Rinuccini; 'La rappresentatione' 'di Anima, et di Corpo ' by Emilio del Cavalieri, with a libretto by Agostino Manni; ' L'Euridice' by Jacopo Peril with a libretto by Ottavio Rinuccini; ' Il rapimento di Cefalo' by Giulio Caccini, with a libretto by Gabriello Chiabrera; 'L'Euridice' by Giulio Caccini, a setting of the same libretto by Rinuccini; 'L'Orfeo' by Claudio Monteverdi with a libretto by Alessandro Striggio; 'La Dafne' by Marco da Gagliano, libretto by Ottavio Rinuccini; and, finally, Monteverdi's ' Arianna', which also had a libretto by Rinuccini. Another way to describe a "hypothetical production" would be "historicized ideal performance text." An "ideal performance text" is an imaginative construct that comes into being along with awareness of a theatrical representation, either present, past or future. It becomes "historicized" when it is created from documentary evidence. My historicized ideal performance texts are not reconstructions of actual performances but readings of the documentary material constantly visualizing the operas in performance. In my thesis I argue that looking at early court operas in the years from 1598 to 1608 from a theatrical perspective organizes the discussion of issues of performance with regard to these operas and allows a pattern to emerge, from early explorations in the staging of sung narrative, to an example of the form fully realized, a decade later. Production values evolve, though not in a linear fashion, from modest to relatively elaborate as the form itself matures and its integrity becomes more able to withstand the pressures of spectacle. In addition, by 1608 early court opera seems established enough to warrant a history of its early development.
The relationship between phonological coding, syntactic awareness, and semantic processing in reading disabled and normally achieving children who were born prematurely

This study examined phonological, semantic, and syntactic processes, from three to seven years, in a group children who were born prematurely. More specifically, the study explored the development of these language processes before the children were exposed to reading instruction. The children were divided into four groups at 7 years: reading disabled with average and low syntactic awareness (RD/NS and RD/LS), and normally achieving readers with average and low syntactic awareness (NA/NS, NA/LS). In addition to phonological and syntactic measures, tests of reading and listening comprehension were administered. To assess comprehension and syntactic skills, the Stanford Binet Memory for Sentences test was divided into six grammatical categories. The transformations into semantically and syntactically correct, as well as semantically correct, but syntactically incorrect, syntactic errors, and complex pronominal relations were examined. The study found that the NA/NS and NA/LS obtained significantly higher scores than the RD/NS and RD/LS on word reading, word attack, and reading comprehension at seven years, showing that syntactic awareness did not have an impact on word reading and comprehension. Significant differences were not found between the groups in the sentence transformations, therefore, subsequent analyses included only the RD and NA. The RD and NA did not differ on their semantically and syntactically correct transformations. However, the RD made significantly more syntactic errors that included sentence fragments at four years and subject-verb agreement errors at five. In multiple regression models, phonological coding was the variable that most consistently contributed to the unique variance in oral cloze, word reading, word attack, and working memory at seven years. Phonological coding and syntactic awareness tasks did not contribute to the unique variance in reading and listening comprehension tasks. This study found that phonological coding limitations had a significant impact on verbatim recall. The reading disabled children by-passed limitations in phonological coding, and syntactic weaknesses, to access higher level inferencing processes that permitted the comprehension and transformation of orally presented sentences with very complex syntactic constructions.
Electromagnetic interference stress testing

An electronic system subjected to the stress of electromagnetic interference may fail to operate normally, just as it may fail under the stress of high temperature. Elevated temperature has traditionally been used as a stress test to "burn-in" electronic systems. The premise is that design flaws and substandard components that would eventually cause a system to fail will cause failure sooner under the burden of a stress test. In this way systems that are sub-standard can be eliminated from the production stream. In this work, electromagnetic interference, rather than elevated temperature, is used as the stress. The focus of this work is on measuring and interpreting the electromagnetic interference required to cause failure as a function of interference frequency and applicator position over the target printed circuit board. In order to measure this failure threshold, an electromagnetic interference stress testing apparatus is designed, including the required hardware and software. The applicator characteristics and the program used to diagnose failures are found to be the key aspects of a successful stress test. The interpretation of the measured failure threshold is aided by theory developed in this work. The theory predicts the dependence of the induced voltage at various positions along a printed circuit board track on the interference frequency and the applicator position. This theory can be used to predict the position on the target track of the device most likely to be causing the failure. Experiments validate both the stress testing apparatus and the theory used to locate failures. Three failures are studied in this work. The first failure occurs due to rectification at a tri-stated driver. The second is a failure due to a weak component: a memory chip functions normally without stress, but retrieves incorrect data when subjected to electromagnetic interference. The final failure is due to timing violations caused by delays induced by electromagnetic interference. For each of these failures, the theoretical prediction of frequency and applicator position effects is verified by comparison with measurements. The combination of theory and experiment described above validates the use of electromagnetic interference as a stress test. Such a test can be used to locate faulty components and design flaws on printed circuit boards.
Contrasting cognitive abilities in children with attention deficit hyperactivity disorder and reading disability

Attention Deficit Hyperactivity Disorder (ADHD) and Reading Disabilities (RD) are common developmental disorders that frequently co-occur. In children who meet criteria for both disorders, it is not known if one disorder is primary, the other secondary or if both true disorders are present. The overall objective of this investigation was to test for the distinctiveness or independence of the two single disorders (ADHD-only, RD-only) and the independence of the two cognitive domains, executive function (EF) and phonological processing (PP), which are proposed as central to ADHD and RD respectively, using a classic double dissociation design. A 2 (ADHD vs. no ADHD) x 2 (RD vs. no RD) model was used to examine the cognitive profile of 4 groups of 17 children each, aged 7-11 years: ADHD, RD, ADHD+RD and controls. The EF tasks involved two measures of inhibitory control, while the phonological measures consisted of 3 tasks varying in level of phonemic processing required. A third measure, locus of control, was employed to investigate the role of attributions in the performance of children on these tasks. The two RD groups (RD, ADHD+RD) were significantly impaired relative to the two non-RD groups (controls, ADHD) on all phonological processing measures. The two ADHD groups were significantly impaired in terms of simple go-task responding relative to the non-ADHD groups and in terms of inhibitory control on both EF measures. Contrary to predictions, an RD effect on inhibitory control was found on one EF measure which involved rapid sequential processing. This finding, together with the ADHD impairment on non-EF aspects of the EF tasks, question the role of inhibitory control as a unique cognitive marker for ADHD. The comorbid group (ADHD+RD) generally exhibited the deficits of both single groups in an additive fashion, suggesting true comorbidity. An external locus of control was found to be associated with ADHD, not RD.
The potential for experiential learning in the transformation of young adults

The educational system often undervalues experiential learning in all its forms, relegating it to a subordinate role with respect to the mandated "essential" curriculum. While there is a current increased appreciation for what experiential learning can offer in terms of teaching practical skills for functioning in society and the workplace, its deeper transformative effects on students may still go unrecognized, be misunderstood or minimized. More study is required on the perspectives of students regarding the transformative benefits of experiential learning and the challenges they face during its process and aftermath. In this study I explore the experiences of fifteen Canadian high school students and the challenges they face during its process and aftermath. beginning in Mexico at the Cuernavaca Centre for Intercultural Dialogue on Development. Employing a qualitative inquiry mode, I describe and analyse student experiences as reporter and participant in order to discern what needs to be considered and in place for future effective experiential learning. The transformative process described in this study not only makes an argument for the inclusion of experiential learning at the core of every curriculum but extracts the qualities and understandings from this unique experience that speak to the enhancement of all educational endeavors.
Postmodern menippeas, the literature of ideas in the age of information

Rumours of the menippean satire's death have been greatly exaggerated. This ancient tradition, long presumed moribund, in fact survives in the intertextual space negotiated by the most dialogic of postmodern satires. Through the pursuit of specific intertextual crossroads between ancient and postmodern texts, this study examines literature as a form of knowledge that competes with other mass and information media in emergent post-industrial societies. The "anatomy" or "menippea," as described by Northrop Frye, Mikhail Bakhtin and others, shares many generic features with postmodern literature, such as skepticism toward totalizing ideological systems, and the "indecorous" miscegenation of various genres of utterance, culled from both "high" literary and popular sources. More significantly, however, menippeas past and present tend to satirize those discursive formations and communications media which achieve hegemony within particular socio-historical contexts, be they based in myth, the printed word, or digital information. Postmodern menippeas use ancient satiric forms to show that "information," far from a uniform datastream, actually comprises a heteroglot complex of discursive subgenres that circulate within both "high" (technical) and "low" (popular) culture. Postmodern menippeanists explore new media and cultural formations in light of very old, pre-novelistic forms of intellectual satire, including symposia, dialogues, and other mixed forms. In particular, this study examines how postmodern texts resuscitate the classical Lucianic 'nekvia', or "dialogue of the dead," to respond to monologic modes of information and communication. For Edgar Allan Poe, Thomas Pynchon, Robert Coover, and Ian Wedde, the so-called "threshold dialogue" provides a means for revitalizing the social dialogue that is increasingly stifled by the "dead speech" of contemporary mass and information media. The menippea, traditionally a genre for critiquing the languages, institutions and apparatuses that legitimize bodies of knowledge, offers these and other contemporary writers critical strategies for demythifying, "unfinalizing," and answering the disembodied messages that haunt the netherworld of the globalized mediascape.