VictorJuiz/thesis huggingface dataset:
The characterization of a novel family C G-protein coupled receptor musGPRC6A

The mouse GPRC6A receptor is a Family C orphan G-protein coupled receptor that shares amino acid sequence identity with the fish 5.24 odorant receptor, the mammalian calcium-sensing receptor and the metabotropic glutamate receptors. Using anti-peptide polyclonal antibodies generated against musGPRC6A, I determined that mouse heart expressed musGPRC6A at the highest apparent level, while lower levels were present day-17 mouse embryos and possibly in tongue. Immunocytochemical analyses of transfected human embryonic kidney cells expressing musGPRC6A showed that the receptor is expressed both on the cell surface and on the endoplasmic reticulum and nuclear envelope. Biochemical studies demonstrated that musGPRC6A is glycosylated at asparagine residues and forms dimers through disulfide linkages. The tissue and subcellular distributions of musGPRC6A have suggested a possible physiological role in regulating heart function, while the ligand activation pattern could be indicative of a role in taste-sensing.
Robustness of simplified simulation models for indoor MANET evaluation

We evaluate the robustness of simplified simulation models for indoor MANET evaluation. A simplified model is robust if the performance results it yields differ uniformly from those obtained with the unsimplified model. Robust simplifications allow researchers to reliable extrapolate simulation results to real-life situations. We show that simplified simulation models are not robust for indoor environments. Experimentation reveals that simplifications affect two MANET routing protocols in disparate manners. Furthermore, even within a single protocol performance trends vary erratically as parameters change. These results cast doubt on the soundness of MANET evaluations using simplified simulation models, and expose an urgent need for more research in this area. Evaluation of Multihop Mobile Ad Hoc Networks (MANETs) is usually performed through simulation. In these studies, it has been customarily assumed that simulation models with no obstacles are acceptable simplifications of the complex mobility and radio propagation conditions expected in actual MANET deployments.
The role of SHIP-1 in the progression of F-MuLV-induced erythroleukemia

SH2-containing inositol phosphatase-1 (SHIP-1) is a negative regulator of the PI3K pathway and acts as an adapter molecule within the Shc/Ras/Erk pathway. Using the Friend murine leukemia virus (F-MuLV) model, it was found that Fli-1 (Friend leukemia integration-1) and SHIP-1 levels were negatively correlated in vivo and in vitro. Furthermore, SHIP-1 was identified as being a gene transcriptionally repressed by the Fli-1 transcription factor. The importance of SHIP-1 in erythroleukemia cells was shown by knocking down its expression using RNAi. Reduction of SHIP-1 resulted in alterations to Epo-responsiveness of erythroleukemia cells. In particular, cells displayed reduced differention capacity and increased proliferative ability. In in vivo studies, mice containing homozygous deletion of SHIP-1 developed F-MuLV-induced erythroleukemia at an accelerated rate when compared to wild-type mice. Therefore, partial or full loss of SHIP-1 contributes to F-MuLV disease.
Involvement of an amino acid transporter in the acid tolerance of streptococcus mutans

Streptococcus mutans, an etiological agent of dental caries, can tolerate and dominate the acidic environment of carious sites (as low as pH 3.0). For this, S. mutans has acid protective mechanisms. To study these mechanisms, acid-sensitive mutants, GTX-B and KLGLUP2 were created by inactivation of a gene designated gluP. Computer analysis suggested that the substrate of the system was a polar amino acid. C14 amino acid transport suggested that the substrate was L-aspartate and competing substrates including glutamate and glutamine. Potassium stimulated the transport of aspartate and glutamate. Significant differences between the parent and mutants were observed in the unadapted and adapted acid tolerance response. Complete operon disruption resulted in a mutant with increased doubling time at neutral and mildly acidic pH. Addition of KPO4 to the growth medium resulted in increased growth yields in all strains. This work demonstrates that amino acid transport via this system is linked to K+ utilization and that inactivation of the system results in diminished growth rates and acid tolerance. Supported by Grant MT-15431 from The Canadian Institute of Health Research.
The local monodromy operator as an algebraic cycle

In this thesis we study a mapping of complex varieties whose special fibre has at worst four-fold singularities. We show that the local monodromy operator and its higher powers are represented by algebraic cycles. Let X be an n-dimensional connected complex-analytic manifold and let Delta be the unit disc. Let f : X rarr; Delta denote a proper surjective morphism, which is submersive (smooth) over the complement of the origin. Then one can associate to f an important topological operator called the local monodromy operator N. The question of representing the monodromy operator by an algebraic cycle, i.e. by intersection with an algebraic cycle, was raised by Kato (cf. [6] page 3) following ground breaking work of Steenbrink (1976, [29]) and is the topic of this thesis, which extends earlier work of Consani (1999, [5]). Algebraic cycles have been a major subject of investigation in algebraic geometry, reflected in the "Standard Conjectures" of Grothendieck, the Hodge conjecture and the Tate conjecture. The monodromy operator corresponds to a class in a cohomology group of a space that is closely related to the generic fibre of f. This space arises as the limit of a spectral sequence that degenerates at the E2-term. The main problem is to find algebraic representatives for cohomology classes appearing in E1-terms of a spectral sequence that degenerates at the E2-term to the cohomology group above, and which induce powers Nr of the monodromy operator in the latter. In this thesis we consider the local monodromy operator at a point in the special fibre. The main problem that we study is to find algebraic representatives of the classes above when n = 4 and f : X rarr; Delta has at worst four-fold singularities (so that every fibre has dimension 3). We find algebraic cocycles [Ni] isin; H2n-2 i-2(S tilde; (2i+2), Q) for each i (see below), which we show represent the monodromy operator and its higher powers except in two special cases. To do this we relate the spectral sequence above to a spectral sequence associated to a suitable resolution of singularities of the fibred product X xDelta X rarr; Delta. The E1 terms of the latter spectral sequence are direct sums of cohomology groups of "strata" given by disjoint unions S tilde; (k) of intersections of components of the special fibre S of the resolution of singularities of X xDelta X. We will find algebraic cycles that represent cohomology classes on the S tilde;(k) which induce Nr in the E2-term. In order to find these algebraic cycle representatives we explicitly compute Chow rings of certain S tilde;(k) using combinatorial constructions from toric geometry and use a theorem of Fulton relating them to the cohomology rings we are interested in.
The "death" of income trusts

This paper looks at the effect that the October 31, 2006 Ministry of Finance announcement that income trusts and other flow-through entities will be taxed like corporations will have on the future of the income trust as an alternative business organization to the corporation. It looks at the structure of income trusts as a business organization and identifies the potential problems inherent to income trusts vis-a-vis the corporate structure. The paper argues that the decision to use income trusts as a business structure was primarily a tax-driven decision since its flow-through ability resulted in less taxes paid by the income trust. The paper concludes that the Ministry of Finance's decision to impose an entity-level tax on income trusts will lead to the decline in use and possible termination of income trusts as an alternative business organization as it will no longer have a tax advantage over the corporate structure.
Acoustic coupling of transverse waves as a mechanism for the label-free detection of biomolecular interactions

This thesis presents the application of the Thickness Shear Mode (TSM) Acoustic Wave Sensor to the study of interactions between biological molecules and between biological molecules and small molecules. The final biological interaction is that between the enzyme Taq DNA Polymerase and a DNA sequence. This is a step in the Polymerase Chain Reaction which is traditionally performed in solution but is being developed here as a surface based technique by immobilizing the Taq enzyme to the surface of the TSM sensor in order to be able to monitor the PCR steps acoustically. This thesis shows that the TSM sensor can be used to detect binding interactions and monitor conformational changes of the HSA. This has been further investigated by applying the principle that molecules containing triple bonds will crosslink in the presence of UV light and that this crosslinking essentially involves no mass change. Monolayers that contain triple bonds and those that do not were exposed to UV light while in the TSM sensor format. The resulting surfaces were further characterized by Secondary Ion Mass Spectrometry. Other interactions that have been studied are those between HSA and the drug cisplatin and HSA and its monoclonal antibody. Four linking systems for the covalent attachment of the biological molecules to the surface of the gold electrode of the sensor were employed, namely thioctic acid, cysteamine, 11-mercaptoundecanoic acid and an N-hydroxysuccinimide ester. All attachment protocols involve the ability of the thiols to form gold-sulphur bonds at the metal surface and be chemically activated at the distal end for covalent attachment. The acoustic parameters associated with the binding interaction of immobilized Human Serum Albumin (HSA) and the drug warfarin where measured on line in real time. Depending on the linking monolayer, different directional combinations of series resonant frequency and motional resistance are observed for the binding of warfarin. These responses are ascribed to acoustic coupling phenomena. It is known that HSA will undergo conformational changes on the binding of warfarin and in the pH is altered. The TSM sensor shows that the HSA and the monolayer itself are affected by pH.
Comparison of computer mediated communication and face to face discourse

The Canadian educational system has many challenges ahead. The reduced funding to school boards, the increased need to accommodate an ever expanding student population, the threat of school safety and the seemingly decreasing support and faith in public education are some of examples of these challenges. A possible solution to some of the challenges is CMC. It is a foreseeable substitute to traditional face to face delivery of educational curricula. This thesis compares the communication behaviors of a group of students in the CMC and F2F environments. The research concludes that CMC promotes some educational advantages compared to F2F delivered courses when combining the previous research findings with the experience of CMC and F2F settings. This investigation may assist students and teachers in the promotion of individual and group understanding of communication and questioning uses.

Keywords: Computer conferencing in education
Communication in education
Teaching
Ultrasound attenuation in the unconventional superconductor SR(2)RUO(4)

Sr2RuO4 is an unconventional superconductor with a critical temperature of 1.5 K. It is highly two-dimensional and of a similar crystal structure as the high-Tc cuprates. In contrast to the cuprates it is believed to be a triplet superconductor. The generic symmetry of the order parameter is p-wave with a full gap in all directions. However recent measurements of heat capacity, penetration depth, thermal conductivity and NMR lattice relaxation time have shown power-law temperature dependences indicative of nodes in the gap. In order to locate the position of these nodes, we performed ultrasound attenuation measurements. At low temperature, changes in the ultrasound attenuation are electronic in origin. When performed at low frequency, in the hydrodynamic limit, the electronic attenuation is proportional to the electron viscosity which is a tensor of rank four. Hence there are six independent elements of which three describe all the in-plane sound modes. A difference in the temperature dependence between these modes can reveal the position of nodes in some cases. We measured the attenuation of four in-plane modes and one out-of-plane mode. Together they describe four of the viscosity components. Our first observation is that the normal state in-plane viscosity is highly anisotropic. Transverse waves polarized in the plane are a thousand times less attenuating when they propagate along the [100] direction than along [110]. In the superconducting state, the T dependence of the attenuation follows a power-law down to 40 mK, or Tc/30. This confirms the presence of nodes in the gap. We also observed some anisotropy in the amplitude and exponent of the low temperature power-laws. This anisotropy is weak suggesting horizontal line nodes instead of vertical line nodes. The best fit to the entire data was obtained with the model of Zhitomirsky and Rice in which horizontal line nodes are present only on two of the three Fermi surfaces, the third one being fully gapped. If this agreement is confirmed by careful calculations, then it would represent compelling evidence for the identification of the gap symmetry.
Generalized measurement and post-selection in optical quantum information

Post-selection is the selection of a subset of an ensemble based on a measurement on that ensemble. In the last few years, post-selection has taken on new importance as a mechanism to induce the optical nonlinearities required for quantum logic gates. I present experiments and theory that explore post-selection in photonic systems. I then go on to describe an experimental implementation of Hardy's Paradox, which is one of the three great thought-experiments about entanglement and correlations in quantum mechanics (the others being the EPR and GHZ "paradoxes"). In the place of the electron--positron annihilation in the original proposal, I apply, for the first time, a post-selection-based absorptive photon switch that coworkers and I had previously developed. Weak measurement promises to be an important technique for characterizing post-selected quantum systems during their evolution. The technique minimizes disturbance to the system and therefore can be used in situ. In a third experiment, I attempt to resolve a recent debate: Which is more fundamental--complementarity or the uncertainty principle? Specifically, can interference be destroyed by a which-path measurement without transferring momentum to the particle? This question is difficult to investigate as any measurement of the momentum transfer causes collapse, severely disturbing the system. I circumvent this problem with the technique of weak measurement and show that which-path measurements do indeed induce a momentum transfer as required by the uncertainty principle. First, I experimentally demonstrate effective nonlinear absorption between two single photons. I show that this photon-exchange effect can be understood as a post-selection induced nonlinearity similar to the one that occurs in Hong-Ou-Mandel interference. In a fourth experiment, I use the latter theory and return to Hardy's Paradox to perform the first weak measurement of an entangled system. I post-select on the paradoxical measurement result while weakly measuring a set of observables. The results are surprising in that they no longer conflict; they now satisfy a classical-logic truth-table. I then proceed to develop theoretically a new method for performing multiparticle weak measurements that is unique because it does not require single-particle-level interactions. This theory provides new insight into the importance of the imaginary component of the weak measurement result.
Teachers' perspectives on ADHD: Development of a valid and reliable measure

The main objectives of this thesis are to provide an updated literature review on teachers' knowledge of ADHD research and to investigate the psychometric properties of a newly developed "knowledge and attitude of ADHD" scale. The findings from the literature review are discussed in chapter 5. The psychometric analysis of the novel questionnaire yielded a reliable 7 item scale from the full questionnaire and was also analyzed separately for knowledge and attitude items. The literature review indicates a significant need for a valid and reliable assessment tool within teachers' knowledge and attitudes of ADHD, research. The novel instrument which was analyzed proves to be a reliable tool; however it needs further development and testing. Firstly, a literature search was conducted which resulted in a systematic review of 15 'teachers' knowledge about ADHD' studies. Secondly, the novel assessment tool was distributed to eighty-three teachers from a rural school board in Ontario.

Keywords: Attention-deficit hyperactivity disorder
Teachers of children with disabilities
Teachers, Attitudes
Genetic analysis of FUSCA3 (FUS3) in Arabidopsis

Genetic studies have identified master regulators of late embryogenesis functions such as the FUSCA3 (FUS3) transcription factor, which play critical roles in the establishment of dormancy and desiccation tolerance in addition to seed storage production. Loss-offunction mutations in FUS3 also result in the replacement of embryonic leaves (cotyledons) with vegetative leaves and constitutive misexpression causes the production of cotyledons in place of vegetative leaves. The mechanisms by which FUS3 influences such a diverse range of phenotypes are not well characterized. Related to this, hormones such as ABA and GA are also known to influence many late embryogenic processes. However, very few studies have used loss-of-function alleles and endogenous manipulation of hormone levels. To study the relationship between FUS3 and hormones, auxotrophic mutants were crossed to a fus3 loss-of-function allele to alter endogenous levels of ABA and GA. Decreasing GA levels or increasing ABA levels were found to partially suppress fus3 mutant phenotypes. Secondly, although fus3 has been extensively used in embryo development studies, its post-embryonic roles have not been explored. A novel conditional phenotype for fus3 was found during seedling establishment. As fus3 seeds desiccate, their viability decreased. The addition of exogenous sugars and high CO2 treatment, however, were able to rescue fus3 seedling lethality. During later vegetative development, a closer phenotypic examination of the heteroblasty of loss-of-function fus3 mutants revealed that these plants accelerated the transition from juvenile to adult vegetative phase. A short pulse of FUS3 after germination can rescue this alteration in leaf phase transition. Using an inducible system that activates FUS3 protein, transcriptome analyses revealed that FUS3 preferentially repressed the expression of transcription factors involved in ethylene action. Moreover, mutations that confer an ethylene insensitive phenotype showed vegetative phase transition defects. Together, these results suggest ethylene plays a downstream role in the FUS3-dependent timing of vegetative phase change. Models are discussed to reconcile how FUS3 can have roles in both cotyledon identity and juvenile leaf transitions by modulating hormone levels and action.
Bi-ventricular repair for hypoplastic left heart syndrome: The control requirements of an intraventricular balloon pump

Hypoplastic Left Heart Syndrome (HLHS) describes a congenital cardiac malformation characterized by the underdevelopment of the left heart. The management of HLHS is palliative and therefore, an alternative treatment promoting biventricular repair is desired. By placing wall stress on the chamber at varying points in the cardiac cycle, it is postulated that ventricular volume can be expanded. The objective of this thesis is to determine if an existing device can be modified specifically to mimic left ventricular pressure and volume overload by altering systolic and diastolic ventricular pressures. It was determined that Intraaortic balloon pump with pneumatic modifications to introduce the aspect pressure volume control would be appropriate to function as an Intraventricular balloon pump (IVBP). Through a neonatal pig model, it has been shown that the IVBP is able to safely mimic pressure and volume overload.
Polymorphisms in the catechol-O-methyltransferase gene (COMT) affect the risk for chronic post-mastectomy pain syndrome (PMPS)

Catechol-O-methyltransferase is an enzyme catabolizing neurotransmitters in pain pathways. Studies associating variations in its gene (COMT ) in several chronic pain syndromes resulted in conflicting reports, prompting the present study that evaluated whether chronic pain in 315 Jewish women with breast cancer >1yr following mastectomy and axillary lymph nodes dissection, can be explained by genoptypes at 5 single nucleotide polymorphisms (SNPs) typed in their DNA. We found significant associations between chronic pain prevalence and genotypes of SNPs rs6269, rs4818 and rs4680, with odds ratio (OR)=2.7-3.4, p=0.025-0.0029, respectively. Two haploblocks were identified, in one of these the ATCA and GCGG haplotypes were seen in 92.7% of women. ATCA_ATCA Carriers had 67.7% less chronic pain compared to ATCA_GCGG carriers (OR=0.3; p=0.009). Since some of these results were still significant after adjustment for multiple comparisons using the False Discovery Rate, we suggest that risk for chronic pain postmastectomy is associated with certain COMT polymorphisms.
Vestibulo-ocular influences on visual feedback utilization during an aerial skill

Purpose. To determine if retinal slip during a back tuck salto affects visual feedback use to control landing stability and if visual information contributes to landing stability after touchdown. Methods. Ten acrobats performed 56 salti under 8 experimental vision conditions: 4 during flight (Full Vision (FL-FV), vision only when the vestibulo-ocular reflex gain (VORg) (FL-VStable), vision only when VOR g (FL-VSlip), and No Vision (FL-NV)) by 2 after touchdown (TD-FV and TD-NV). VORg was obtained in real-time and vision was manipulated using occlusion spectacles. Landing stability was analyzed by 2 judges and by assessing kinematics in the 1st second after touchdown. Results. Judging scores revealed that TD-FV yields better performance than TD-NV while the kinematic analyses revealed some influences of vision in-flight. Conclusion. Vision after touchdown significantly contributes to overall landing stability but vision in-flight can, with or without retinal slip, influence how stability is reached.
UV/titanium dioxide for drinking water treatment: Concurrent degradation of 1,4-dioxane and removal of iron and manganese

An advanced oxidation process using ultraviolet light and titanium dioxide (UV/TiO2) was evaluated at pilot and bench-scale for the concurrent degradation of 1,4-dioxane and removal of iron and manganese through adsorption onto the TiO2 surface. Both studies showed that UV/TiO2 was a feasible process for the concurrent treatment of all three compounds. Iron was completely removed under all tested conditions, while manganese required elevated pH. 1,4-Dioxane did not inhibit the treatment of iron and manganese, but 1,4-dioxane degradation was hindered by these metals presumably by competitive adsorption onto the TiO2. Ultimately, however, conditions were identified where all three compounds could be concurrently removed. The results from this work point to a potential new process that can meet concurrent treatment objectives while minimizing cost through process consolidation.