VictorJuiz/thesis huggingface dataset:
A geophysical interpretation of the crustal structure and tectonic evolution of the Western Superior Province

This study addresses the crustal structure and the tectonic evolution of the western part of the Archean Superior Province, based on the interpretation of its regional gravity field with constraints from Lithoprobe seismic data. In addition, by using techniques of enhancement of magnetic data, and integration of various geophysical datasets, the detailed structure of the metasedimentary English River belt is investigated in order to clarify the tectonic significance of this type of terrain, and to understand the processes accounting for its characteristics. The results indicate that post-accretionary processes had a dominant contribution in defining the current structure of the Western Superior Province (WS), especially at deeper levels of the crust. With the exception of the top 10 km, the crust of the WS is characterized by vertical density stratification and lateral mass homogeneity, reflecting post-accretionary reorganization of the crustal structure through processes of vertical mass transfer and ductile lateral flow, which are related to a major episode of mid- to lower-crustal softening that occurred between ca. 2.71 and 2.66 Ga. The topography of the crust-mantle interface was also significantly influenced by late-orogenic processes, such as crustal extension and vertical mass redistribution, although some of its features may have originated from the accretionary or collisional stages of the WS tectonic evolution. In addition, the WS preserves a record of post-orogenic modification of the lower crust through processes of magmatic intra- and underplating, possibly related to the development of the 1.1 Ga Midcontinent rift. Detailed investigation of the structure of the metasedimentary English River belt confirms that this terrain does not represent an ancient accretionary prism, as initially thought. Its structure is consistent with alternative interpretations of such terrains as remnants of syn-orogenic deposits accumulated in response to the deformation, uplift, and erosion of bounding volcanic arcs. The English River belt contains evidence of a major post-accretionary extensional episode at ca. 2.70 Ga that affected all levels of the crust, and which ultimately may explain the high-temperature, low-pressure metamorphism of the English River sediments.
Nonlinear optical characterization of novel Kerr materials for ultrafast all-optical signal processing

In this thesis we report the nonlinear optical characterization of three novel Kerr media for ultrafast all-optical switching and laser technology applications. Using a tunable picosecond laser system and the Z-scan technique we measure, for the first time, the wavelength dependence (λ = 800–1600 nm) of the nonlinear refractive index and the nonlinear absorption coefficient of the conjugated polymers ADS111RE and CN-PPP and the laser crystal Yb:KGW. Similar measurements on a variety of reference materials, that include the silicate glass SF-59 and five common solvents, show a good agreement with the predictions of existing theoretical models and the few scattered experimental data available in the literature, thus verifying the accuracy of our experimental results. The principal conclusions, drawn by comparison with existing materials and figure of merit calculations, show that ADS111RE is an attractive material for all-optical signal processing at wavelengths larger than 1400 nm and that Yb:KGW is an excellent candidate for efficient Kerr lens mode-locking operation. Furthermore, we present a refined evaluation of the theory and practise of Z-scan, and we demonstrate a method to fabricate polymer films of good optical quality and thickness up to few millimeters, that is particularly useful for Z-scan experiments.
Focal-plane CMOS algorithmically-multiplying computational image sensor

Various video processing tasks such as video compression and pattern recognition require computationally expensive real-time spatial image transforms computation. The computational CMOS imager computes a two-dimensional correlation of each video frame with a programmable digital kernel of up to 8 x 8 pixels directly on the focal plane. Selective pixel output sampling controlled by binary kernel coefficients implements binary-analog multiplication. Column-parallel accumulation of pixel outputs is implemented by switched-capacitor integrators for each binary weight. Binary-weighted summation and concurrent quantization is performed by a bank of column-parallel multiplying analog-to-digital converters (MADCs). A simple digital adder performs row-wise accumulation during ADC readout. A 128 x 128 active pixel array integrated with a bank of 128 MADCs was fabricated in a 0.35mum standard CMOS technology. The 4.4mm x 2.9mm prototype is experimentally validated in discrete wavelet transform (DWT) video compression and frame differencing and yields a computational energy-efficiency of 4.3GOPS/W at 30 frames per second (fps).
Epistemic agency and pervasive knowledge building in a grade two classroom: examining the potential of handhelds in collaborative inquiry

The central goal of this thesis is to engage students in new pedagogies that enable them to take control of their own knowledge advancement and allow such pursuit to pervade all aspects of mental life. This study describes a design experiment examining the use of handheld computers in a grade two knowledge-building classroom. Specifically, the focal problem under investigation asks, how can the technological affordances of inexpensive handhelds be directed towards the support of pervasive knowledge building and epistemic agency? Researcher observations are documented over a six-week period as a number of innovations utilizing collaborative inquiry are designed for use within a technologically enriched grade two classroom (N = 22). Findings suggest that handhelds can be an effective technological assist in the knowledge-building classroom and there is some evidence to suggest that handhelds may have a role in fostering epistemic agency. Implications of these findings for computer-supported collaborative learning environments are explored.

Keywords: Learning, Psychology of
Teaching, Computer-assisted instruction
Educational technology
Education, Primary, Computer network resources
Education, Primary, Computer-assisted instruction
Human-computer interaction
Electromagnetic simulations of nanooptics based on the Finite Difference Time Domain (FDTD) method

Electrodynamic simulations based on the Finite Difference Time Domain (FDTD) method were used to investigate the transmission properties of periodic nanohole arrays in opaque metal films surrounded by dielectric media. It is believed that the mechanism for extraordinary transmission through these nanoarrays involves the coupling of evanescent Surface Plasmon Polariton (SPP) fields to the momentum of the array. Theoretical calculations performed show that transmission peak positions depend on the periodicity (separation) of the holes and changes in the surrounding dielectric environment. Additionally, polarization effects, unconventional aperture shapes and interactions between localized surface plasmons of individual apertures were analyzed. The combination of surface plasmon generated fields, their sensitivity to contacting dielectric medium, and the tunable properties of these periodic arrays provides insight into the potential design of novel chemical biosensors.
Processing of visual information in the functional field of view: the effects of stimulus, task, and motor response on latency and accuracy of performance

The aim of the present work was to examine the effect of perceptual load and target eccentricity on accuracy and latency of information processing. Perceptual load was altered in two studies by manipulating: (1) stimulus characteristics (set size, discriminability), (2) goal of the task (detection vs. identification), and (3) motor responses (ocular vs. manual, point vs. press). In support of the hypothesis, results from study 1 showed increased reaction times and decreased accuracy with increasing perceptual load. As predicted in study 2, manual press was initiated more slowly compared to pointing. In addition, pointing was initiated faster when accompanied by a saccade. In conclusion, perceptual load significantly affected information processing in the functional field of view (FFV). These results can be used to develop a clinical assessment tool for patients with visuospatial neglect who might have a general deficit in processing capacity.
Spectral element methods for the stokes problem

A spectral element code is developed by modifying a existing standard finite element method code. Hierarchical bases constructed from Jacobi polynomials are used, requiring changes to elemental operations such as integration and differentiation. First, the mass matrix is validated through a Galerkin projection. Both h and p convergence results are reported. The convergence rates in the L2 error norm are P+1, where P is the expansion order. Second, the Poisson problem is solved to validate the stiffness matrix. Both h and p convergence is shown, although with slightly reduced convergence rates due to corner irregularities. Finally, the Stokes problem is solved through the Uzawa algorithm. Similar results as to the Poisson problem are obtained. In conclusion it is found that spectral element methods are more efficient both for the CPU times and for memory requirements compared to obtaining a similar accuracy finite element method solution.
Matrix converter and its application in a micro-turbine based generation system

The MC should provide (i) frequency conversion from the source-side (0.4--4 kHz) to the load-side (50/60 Hz) and (ii) magnitude and phase-angle control of the load-side terminal. Exploiting the high frequency ratio of the source- to the load-side of the MC, a new switching strategy for the MC is introduced. Control mechanisms for the magnitude and the phase-angle of the MC load-side are developed. Local and global stabilities of the MC operation, based on the introduced switching strategy and control mechanisms, are analytically verified. This thesis investigates the technical feasibility of applying a three-phase, AC-AC Matrix Converter (MC) as the interface medium between a high-speed (40 to 120 krpm) Micro-Turbine based Generation (MTG) system and the load system. The main motivation for using the MC instead of a conventional AC-DC-AC converter is that it eliminates the DC-side components of the AC-DC-AC converter, e.g. the DC-link capacitor. This increases reliability and reduces size, weight and footprint. This thesis also introduces an overall control scheme for a micro-turbine generator system which is interfaced through the MC to a utility system as a Distributed Generation (DG) unit. To develop a systematic control design for the MC, a new comprehensive mathematical model of the MTG system, including the MC, is presented. This mathematical model is based on transformation of the network equations of the MC source-side to a frame named switching reference frame and then deducing the overall system equations in the MC load-side dqo reference frame. All analytical results and control strategies are verified based on digital time-domain simulation studies in the PSCAD/EMTDC software environment.
Structural and functional characterization of yeast histone deacetylase Hos3

Several key residues were identified as being catalytically important in Hos3 since they inactivated the enzyme when they were mutated to alanine but left it structurally intact as revealed by circular dichroism and gel filtration chromatography. From sequence alignment these residues correspond to key catalytic residues in HDLP. Combined with the fact that both Hos3 and HDLP require a zinc ion, these results strongly suggest that Hos3 has a similar catalytic mechanism to that proposed for HDLP. With the use of chemical labeling and mass-spectrometry, Cys 197 and Cys 456 were identified as having free sulfhydryl groups. By mutating Cys 197 to alanine, aggregation of Hos3 was substantially reduced. In addition, a systematic deletion analysis revealed that Hos3p can be trimmed by more than 150 residues from its C-terminus, and is still active. However, systematic N-terminal truncations revealed that Hos3 cannot tolerate deletions of more than 30 residues.
VTC0: A second-order theory for TC0

We introduce a finitely axiomatizable second-order theory VTC 0 and show that it characterizes precisely the class uniform TC0. It is simply the theory V0 [12] together with the axiom NUMONES, which states the existence of a "counting array" Y for any string X : the ith row of Y contains only the number of 1 bits upto (excluding) bit i of X. First, we introduce the notion of "strong DB1 -definability" for relations in a theory, and use the recursive properties of TC0 relations (rather than functions) to show that TC0 relations are strongly DB1 -definable, and TC0 functions are SB1 -definable in VTC0. Then, we generalize the Witnessing Theorem for V0 [12], and obtain the witnessing theorem for VTC0 from this general result: exist;SB0+ SB1 theorems of VTC0 can be witnessed by TC0 functions (here, SB0+S B1 formulas are those obtained from SB1 formulas using and;, or; and bounded number quantifications). Finally, we show that VTC0 is RSUV isomorphic to the first-order theory Db1 -CR, which has been claimed the "minimal" theory for TC0 [20]. This isomorphism shows that VTC0 admits the SB0+D B1 comprehension rule. Hence, in VTC0, strong DB1 -definability and the usual DB1 -definability coincide. It also follows that Db1 - CR = Db1 - CRi, for some i. This answers affirmatively an open question from [20].
Synthesis, characterization and electrochemical evaluation of lithium-manganese phosphates for cathode material in lithium ion batteries

Lithium ion batteries deliver the highest specific energy and energy density of commercially available secondary batteries. The objective of this study was to evaluate lithium-manganese phosphate (LiMnPO4) for potential application as a cathode material in lithium ion batteries due to its high theoretical capacity and stable phospho-olivine structure. LiMnPO 4 was successfully synthesized via a novel aqueous sol-gel process under an inert nitrogen and air atmosphere. Microstructural design strategies including annealing treatment and the addition of 1 wt% copper dopant were evaluated in order to improve the electrochemical performance of the LiMnPO4 cathode. The cathode particle microstructure and morphology were characterized using X-ray diffraction and scanning electron microscopy. Open circuit voltage was 4.1 V for all samples. The electrochemical performance of LiMnPO 4 is significantly improved by the addition of a dopant in an inert nitrogen atmosphere with a specific capacity of 28 mAh/g achieved during the first discharge cycle.
The relationship between language ability and performance on a low-verbal false-belief task in normally developing 3- to 5-year-old children

Previous research has established that language ability is related to false-belief understanding. However, the relation between the two constructs may be confounded by the linguistic demands of the standard verbal false-belief task. The present study examined whether performance on a false-belief task with reduced linguistic demands is positively related to (a) general language ability and (b) understanding of complement structures in 3- to 5-year-old normally developing children. Performance on the low-verbal false-belief task was positively correlated with the general language ability measure. However, after age of the children was controlled, this correlation did not remain significant. Also, it was found that children who had a perfect score on the complements task performed better in the false-belief task than those who did not succeed on all items of the complement task. The study thus highlights the various and complex ways in which language and false-belief understanding are related.
Blaise pascal on skepticism and order

This work is a study of Blaise Pascal's Pensées. It proposes to show the way in which Pascal's philosophy of mind—his conception of order and the relation of reason, the emotions, and the will to the self—which emerges from his skepticism, can be used to draw out his views on morality, despite the fragmentary state of the work. The thesis begins with a consideration of the three major philosophical precursors to Pascal's project: Augustine, Montaigne, and Descartes. It continues with an account of order in the Pensées, centering on the heart, the two minds, and the three discontinuous orders, connecting Pascal's views to those of a number of 20th century analytic philosophers. It goes on to consider the order of the body (law and politics; diversion) and the order of charity (human greatness and wretchedness; the wager; habit and authority) in specific detail, showing how Pascal discusses each of these through a dialectical process that begins in a pre-critical, unreflective state, moves through a first, rational and philosophical, criticism, and finally turns that criticism against philosophy itself. The thesis concludes by briefly considering three figures whose ideas, to some extent, carry on and expand those of Pascal: Rousseau, Maistre, Tocqueville.
The development of a hydrogel-supported phospholipid membrane for the reconstitution of transmembrane proteins

The overall objective of this work was to make a hydrogel-supported phospholipid bilayer that models a cytoskeleton-supported cell membrane. Hydrophobic anchors attached to a hydrophilic hydrogel surface were proposed to promote the adhesion of liposomes and cause the self-assembly of a phospholipid bilayer membrane on that hydrogel surface. The phospholipid-hydrogel conjugate, called the pre-Lipobead, was composed of a crosslinked poly(dimethylacrylamide) core and surface-grafted phospholipids. Using a one-step radical suspension polymerization scheme and phospholipids in which reactive vinyl groups had been attached, the anchors preferentially located at oil-water interfaces during pre-Lipobead formation and through their vinyl groups, became covalently attached at the hydrogel surface. X-ray photoelectron spectroscopy and laser scanning confocal microscopy confirmed surface localization of the anchors. Upon mixing the pre-Lipobeads with liposomes, a lipid membrane readily self-assembled around the hydrogel surface, forming the Lipobeads. The synthesis scheme allowed control of surface anchor density and thus potential control of membrane properties. The properties of the formed Lipobead membrane were investigated by fluorescence quenching and fluorescence-recovery-after-photobleaching (FRAP). The quenching of fluorescently labeled phospholipids (PC-NBD) in the Lipobead suggested that the formed membrane was mostly a bilayer. The lateral diffusivity of PC-NBD in the membrane, measured by FRAP, was found to vary with the surface anchor and hydrogel crosslinking densities. The Lipobead membrane could form a diffusion barrier to large hydrophilic solutes such as dextran, but permeable to small ions such as Ca2+. The ability of Lipobeads to incorporate transmembrane proteins was investigated by incubating proteoliposomes containing muscarinic m2 acetylcholine receptors with the Lipobeads. Fluorescent antibodies that target an extracellular fragment of the receptor coupled with confocal microscopy revealed the presence of receptors on the Lipobead surface with some proteins reconstituted in the right orientation. Specific binding of an antagonist to those reconstituted receptors indicated that the drug-binding pockets were intact and the reconstituted receptor density was between 132–152 receptors/μm2, a value comparable to receptor density on cardiac cell surfaces. The hydrogel-supported bilayer membrane shows promise as a new tool for studying membrane and transmembrane protein biology, as well as potential applications in high throughput drug screening, diagnostics, and drug delivery.
Effects of a classroom-based direct instruction reading intervention for young children with sickle cell disease

Children with sickle cell disease (SCD) are at increased risk for early learning and academic difficulties, independent of their stroke status. The efficacy of empirically-tested academic interventions to remediate learning difficulties in SCD has not yet been described. In the current study, a Direct Instruction (DI) reading intervention targeting decoding and phonological awareness skills was administered to 12 early elementary school students with SCD (M age = 6.32 years) without stroke and presenting with early reading difficulties as part of an intensive 16-week program. Pre-DI psychoeducational profile revealed a pattern of globally depressed scores within 1 SD of the mean on IQ, academic, and visual-motor measures. Significant improvement in word reading and a trend for improved non-word decoding was found pre-test to post-test, but no improvement in reading fluency, spelling, and math outcomes was observed. Findings are discussed in the context of the SCD neurocognitive literature and future directions proposed.

Keywords: Sickle cell anemia in children
Reading, Remedial teaching
Factors influencing the reliability of self-reported occupational exposures

In a case-control study of prostate cancer, self-reported and expert assessments of occupational exposure were recorded. Using longest jobs and excluding agreement on “never” exposure, differences between the two estimates were characterized. Agreement ranged from 46.1% for PCBs to 68.1% for sunlight. Agreement decreased for more subjective indices of exposure and varied within indices. In multiple logistic regression models, the occupational and respondent characteristics associated with asbestos and PAH underreporting differed from those for overreporting. Factors also differed between agents and the two exposure indices—except white-collar status, which was consistently associated with overreporting. In one model, cancer cases perceived 10 exposures to pose lower health risk than controls; in another, low job satisfaction was associated with overreporting magnitude of PAH exposure. Expert consistency and other associations with risk perceptions were also explored. Understanding questionnaire design factors and personal characteristics that influence exposure reporting may help to achieve more valid estimates of disease risk.
Functional convergence of crassulacean acid metabolism: A study of functional anatomy in a convergent photosynthetic pathway

Increased cell size, increased leaf succulence, reduced intercellular air space (IAS) and reduced surface of mesophyll exposed to IAS (Lmes) are traits associated with the Crassulacean acid metabolism (CAM) photosynthetic pathway. I tested whether these anatomical and structural traits were related to increased CAM function across eight CAM species, as measured by overnight acid accumulation, CO2 assimilation, CO2 uptake and length of CAM and C3 phases. Increased cell size and leaf succulence are important for overnight acid storage, and were positively related to CAM function. Reduced IAS and Lmes were positively related to CAM function, and were negatively related to C3 function. These results support my hypothesis that reduced IAS and Lmes are beneficial for CAM function through the reduction of CO2 efflux and the improvement of carbon economy. However, reduced IAS and Lmes limit C3 photosynthesis, generating a bimodal distribution of weak and strong CAM species with high and low IAS and Lmes values, respectively.