VictorJuiz/thesis huggingface dataset:
A system for the production of human monoclonal antibodies

The ability to maintain antibody secreting human B lymphocytes in culture is important for studies into B cell repertoires and for monoclonal antibody production. The CD40 culture system stimulates B lymphocytes to allow for ' in vitro' expansion and immunoglobulin secretion (17). We have used a CD40 ligand expressing (CD40L+) fibroblast feeder layer which we have transfected with cytokine genes (IL-10, IL-6, IL-4 and IL-2). EBV-transformed lines grown on the cytokine-transfected feeder layers demonstrated similar patterns of immunoglobulin secretion as cells grown on the CD40L+ line with exogenously added cytokines. IL-10 and IL-6 were able to increase immunoglobulin production of four EBV-transformed cell lines, whereas IL-2 and IL-4 did not have any effect at the concentrations used in either the cytokine-transfected lines or with the exogenous cytokine. Thus these cytokine secreting CD40L+ feeder cell lines will be a valuable tool for the 'in vitro' culture of human B lymphocytes.
Characterizing the physiologic roles of TRAF6 using TRAF6-deficient mice

The ability of cells to respond and adapt to changes in the environment is contingent on the delivery of messages initiated at cell surface receptors to the nucleus, where appropriate genes can be switched on or off. The tumor necrosis factor receptor (TNFR) superfamily consists of a growing number of cell surface receptors that mediate diverse physiological functions with the help of intracellular adapter proteins called TNFR-associated factors (TRAFs). The six mammalian members of the TRAF family share conserved carboxy-terminal domains and, excluding TRAF1, contain amino-terminal ring finger domains thought to be pivotal for downstream signaling. Heretofore, little was known of the roles of TRAF6 'in vivo'. To determine the physiological roles of TRAF6, I generated TRAF6-deficient mice. The findings, presented in Chapter 2, provide evidence that TRAF6 is important in multiple pathways. Firstly, TRAF6 is critical in interleukin-1 (IL-1), CD40 and lipopolysaccharide (LPS) signaling. Secondly, TRAF6-deficient mice are osteopetrotic due to impaired osteoclast function. Thirdly, TRAF6 is essential in perinatal and postnatal survival. In chapter 3, the role of TRAF6 in perinatal survival was addressed by examining TRAF6-deficient embryos. Evidence is provided that deletion of TRAF6 results in exencephaly, failure of neural tube fusion and site-specific aberrations in programmed cell death (PCD) within the developing CNS. This work solidifies the 'in vivo' roles of TRAF6 as a key regulator in inflammatory pathways, cytokine signaling, bone metabolism, postnatal survival, neural tube fusion and PCD during development and provides a solid foundation for future studies regarding the as yet uncharacterized roles of TRAF6.
Adaptive Bayesian Information Filtering

A new approach to 'interactive information filtering' is presented: 'incremental' Bayesian inference is applied to a multinomial model of text-document relevance as a means of 'learning user information needs' over extended periods of time, through interactive data sampling. An information filtering agent acts autonomously on a user's behalf by filtering on-line document streams for text documents that are relevant to the user's information need and forwarding such documents to the user. For each forwarded document, the user is prompted to 'confirm' or 'deny' its relevance; a filtering agent that is able to incorporate such user 'feedback' into its decision process can significantly improve its future document selection accuracy. In contrast to nonprobabilistic information filtering models, which are based on heuristics and ad hoc techniques, the proposed probabilistic model provides a theoretical foundation for interactive information filtering. During empirical trials, the proposed probabilistic model has shown improved performance for certain measures, relative to nonprobabilistic models.
Regulation of protein tyrosine phosphatases by glucose

Exposure of tissues to high glucose concentrations (HG) induces a number of alterations in cell signalling. The role in these effects of protein tyrosine phosphatases (PTPs), key enzymes regulating the extent and duration of tyrosine phosphorylation, has not been studied. 'Hypothesis'. HG will cause changes in PTP expression and activity which contribute to the effects of HG on signalling. 'Results'. Exposure of rat adipocytes to HG with insulin and cultured rat mesangial cells (MCs) to HG caused an increase in protein content of transmembrane PTPÃ, but no change in the intracellular SHP2 or PTP1B. Transmernbrane PTP LAR was detected only in adipocytes and was decreased. Specific activity of PTPÃ was not altered in adipocytes, but decreased in MCs. HG is thought to modulate its effects in MCs by PKC activation and PKC downregulation with phorbol myristate acetate blocked the increased in PTPÃ by HG. The cytosolic tyrosine kinase Src, a substrate of and activated by PTPÃ, was increased by HG in protein but specific activity was decreased by HQ consistent with decreased activity of PTPÃ. 'Conclusion'. HG causes changes in cellular PTPs which may contribute to the altered signalling observed.
A search for the mammalian brain site(s) mediating occasion setting learning

Using a conditional contextual discrimination paradigm, I have been able to simultaneously assess two types of learning: A complex occasion setting learning and a simple Pavlovian learning. An occasion setter is a discriminative cue (feature) that predicts whether or not a target stimulus is followed by a reinforced event (US). Behavioural evidence has demonstrated that discriminative control of the occasion setter does not rest with simple excitatory associations between the feature and the US or between the feature and the target stimulus. In all of the experiments presented here, one context (feature) predicted that access to a saccharin solution (target) would be followed by a LiCl injection (US), while a second context predicted that the identical saccharin solution would be followed by a saline injection. All control animals learn to suppress fluid consumption in the first relative to the second context (occasion setting) and all acquire an aversion to the LiCl paired context on a subsequent place test (Pavlovian learning). Pavlovian aversions to the "danger" context can be abolished and the occasion setting properties remain intact. Having demonstrated a behavioural double dissociation between the types of learning, the focus of this thesis is to identify the neuroanatomical loci mediating the two separate learning systems. (Abstract shortened by UMI.)
A new method for the measurement of airborne formaldehyde using derivatization with 3,5-bis(trifluoromethyl)phenylhydrazine

A new method is described and validated for the measurement of airborne formaldehyde using solid phase extraction (SPE) cartridges impregnated with 3,5-bis(trifluoromethyl)phenylhydrazine (TFMPH). Analysis by gas chromatography with electron capture detection (GC-ECD) provides a detection limit of 74 ng formaldehyde per sample. A field study was conducted to compare the use of this method to the US Environmental Protection Agency (EPA) method TO-11, which uses 2,4-dinitrophenylhydrazine (DNPH) and the National Institute for Occupational Safety & Health (NIOSH) chromotropic acid (CTA) method (NIOSH method 3500). Samples were collected from a variety of indoor and outdoor environments known or suspected to contain formaldehyde, Use of TFMPH with GC-ECD analysis correlates well with both methods (R2 = 0.93, slope = 1.09 vs. DNPH; R2 = 0.96, slope = 1.01 vs. CTA). Spiked samples were shown to be stable at least 14 days when stored at -20°C. Analysis of samples by gas chromatography-mass spectrometry with selected ion monitoring (GC-MS/SIM) has also proved feasible, with a detection limit comparable to that obtained by GC-ECD. All instrument calibrations were carried out by vapour spiking precise masses of aldehyde onto the sampling cartridges. For field sampling at environmental concentrations (<25 ppbv) of formaldehyde, oxidation of the formaldehyde-TFMPH hydrazone can be corrected for through the use of potassium iodide ozone scrubbers and by performing an 'oxidatian blank' subtraction from the standard curve. Laboratory and field results show the use of TFMPH to be viable for quantifying airborne formaldehyde in occupational and environmental samples. Also demonstrated is the potential for applying TFMPH as a derivatizing agent for measuring other airborne carbonyls.
Age Differences in Rate of Forgetting

Normal aging is associated with changes in cognitive function as well as structural and functional neuroanatomical changes. This study investigated the relationship between age-related changes in cognitive and neuroanatomical function using a well-known neuropsychological test, the Brown-Peterson task. This task may be capable of dissociating memory processes dependent on medial temporal dysfunction and attentional processes related to frontal lobe functioning. A variation of the task was developed to control for extraneous factors that may have confounded the results of previous Brown-Peterson studies of aging. The results indicate that aging is not associated with an accelerated rate of forgetting. Rather, the increased slope of the forgetting function is attributable to age-related deficits in secondary memory, possibly arising from frontal dysfunction.
The effects of war on children, an ecological integration

The purpose of this study was to extend Elbedour, Bensel & Bastien's (1993) model of development for children of war to an actual population. This research aimed at rectifying the lack of comparative analysis within war literature, constructing upon it through inclusion of the variable culture. The frequently overlooked Sri Lankan population was examined, investigating children exposed to various war traumas, including war orphans and refugees, children orphaned for reasons other than war and a comparison group. Measures of cognitive maturity, interviews and observations were used to understand the children's ecological environments and their role in mitigating effects of war. Results revealed that children who appeared most adjusted, performing more successfully on cognitive tests resided in ecologically stable environments, characterized by healthy, interactive relationships across all subsystems. This was in contrast to children who appeared maladjusted and unable to complete the cognitive tests, whose ecological environments reflected social insolation and impoverishment across all subsystems.
Variation in wood pH and its impact on resin cure in oriented strand board, OSB

The variation of pH was investigated in wood strands and log sections of aspen and birch in relation to certain process parameters employed in the manufacture of oriented strand board (OSB). Mine member mills of the Structural Board Association provided green and dry wood strands from winter and summer harvested logs. The acidity of samples from summer harvest was higher than those from the winter. Wood acidity increased with drying temperature and time, as well as duration of storage. A negative correlation was found between wood pH, acid buffering capacity and gelation time with four different phenol-formaldehyde resins. The internal bond strength of laboratory made boards was positively correlated with strand pH. This study demonstrated that wood acidity had a marked influence on the curing of phenol-formaldehyde resins and on the adhesive bonding of wood. It should not be construed, however, that wood acidity is the only factor affecting its bonding.
Flutter of flexible tubes in sub- and supercritical flows

This study is composed of two parts: In part I, the stability behavior of a finite length uniform planar channel conveying fluid is examined for application as a model of forced expiration and wheezing observed in obstructive airway diseases. Using the Galerkin finite element method, it is shown that subcritical flutter occurs due to the presence of fluid dissipation; this is followed by buckling (onset of flow limitation) as the flow speed exceeds the wave speed. However, the results show that the flutter predicted has a weak growth rate and that a uniform channel assumption may be inappropriate for a model of wheezing. Therefore, in part II, we have modeled a nonuniform planar channel that is a two-step procedure: In the first step, a nonlinear analysis is carried out to obtain equilibrium solutions for a collapsible airway conveying sub- or supercritical flow. In the second step, a linear stability analysis of the nonuniform channel is performed that predicts two distinct modes of flutter: a weak growth high frequency flutter due to energy loss downstream and a sudden strong growth low frequency flutter that appears to have a causal link to the onset of flow limitation.
Negotiating meaning in writing conferences, an investigation of a university Japanese-as-a-foreign language class

Conceived within the frameworks of cultural-historical activity theory, systemic functional linguistics, and situated literacy, this study investigates the form and function of writing conferences in a university foreign-language class, focusing on the relationship among the teacher-student discourse in conferences, students' subsequent text revisions, and other factors affecting their modes of engagement with the writing activity. The study involved 9 students who, over the course of 1 semester, composed texts on 3 different topics as part of classroom activities. Then in conferences with the teacher, they discussed their first drafts, produced second drafts, and, in interviews, reflected on the processes involved. The main sources of data consisted of audio-recordings of the conferences, the students' written products, both first and final drafts, audio-recordings of 3 retrospective interviews, and a questionnaire concerning their ethnolinguistic background. The triangulated sources of data were analyzed through the combined use of quantitative and qualitative methods. Overall, the analyses pointed to the positive effects of the tripartite writing activity. The students as a whole utilized the majority of specific pointers offered during the conferences to revise their first drafts. They also reported the metalinguistic and metacognitive value to them of engaging in the process. Quantitative analyses of the conference discourse and of the relationship between the discourse and the students' revisions showed that the manner in which the students engaged in the writing-related activities was strongly influenced by the revision goals they set themselves, the topics selected for discussion in the conferences, and their target language proficiency. Additionally, qualitative analyses of 5 mini-case studies revealed that, in accounting for the students' differential performance, other factors, which appeared to cut across the proficiency differences, interacted with their target language proficiency in an intricate yet dynamic way. The study suggests the importance of: (a) exploring teacher-student interaction in terms of discourse theory; (b) examining overall patterns of intertextual relationships between students' text revisions and talk around their texts; and (c) taking account of the multiple contexts that shape and are shaped by the writing activity. Methodological and pedagogical implications are also discussed.
Models of tissue bonding to bioactive glass in vitro

Silica based bioactive glasses, such as 45S5 type Bioglass® , have been shown to bond to both hard and soft tissue. The tissue bonding ability of such bioactive glasses is due to the formation of a hydroxycarbonate apatite surface reaction layer, which is formed as a result of ion-exchange at the chemically reactive surface. It is also known that the first matrix to be produced during de novo bone formation is cement line, which is now experimentally feasible in vitro by using rat bone marrow cells in osteogenic conditions without ascorbic acid. This work has shown the interdigitation of cement line with the surface reaction layer in vitro. The relative attachment of collagen fibres in vitro to the surface, with and without cement line was also studied, as models of de novo bone formation and soft tissue bonding, respectively. Incorporation of organic moieties at the surface was also demonstrated by XPS.
Cultural displacement and dislocation, darwinian fictions of empire, 1850-1900

In this dissertation, I examine the nexus, or rather interplay, of Darwinian evolutionary theory and other modes of cultural discourse; I explore the diverse and multiple ways in which Darwinian evolutionary theory is appropriated to alternatively disrupt and buoy cultural ideologies of empire. In the Introduction, "The Positively More 'Social' Darwin," I attempt to locate Darwin's thesis within its general historical context and relate it to developments in intellectual history. In Chapter 1, "Walter Bagehot; or, Physics, Politics and the 'Selling of Figs,'" I analyze Bagehot's attempt to represent the unique English political character not just as a product of evolution but as the ultimate (though not necessarily the inevitable) expression of it. in Chapter 2, "'India Orientalis ' or 'England in the East': Imag(in)ing India and the Crisis of Representation," I argue that whereas in other colonial encounters the British had no difficulty in asserting their hegemony, India challenged basic assumptions about language, culture, and racial hierarchies, forcing the British to reevaluate their representation of themselves and the Empire. The chapter ends with a discussion of Dilke's Greater Britain, a work which problematizes progress and liberty by imparting a new grammar of domination and relying on Darwinian tropes. In Chapter 3, "'Administrative Nihilism': The Evolution of Ethics After Darwin," I analyze three utopian fictions, Butwer-Lytton's The Coming Race, Butler's Erewhon, and Wells' The Island of Doctor Moreau in light of Huxley's concern about the failure of Darwinian evolutionary theory to adequately address the social and ethical implications of evolution. In Chapter 4, "Righting Evolution: Women's Responses to Darwin," I examine how maternity was isolated and variously problematized by women writers concerned with Darwin's marginalization of women. I analyze the work of Cobbe, Linton and Gilman in conjunction with various New Woman and 'contra' New Woman authors, whose alternative views of sexual selection challenge not only Darwin but the assumed privilege of heredity, class and gender. in Chapter 5, "Uncle Tom's Cabin and Daniel Deronda and 'the mystical enthusiasm for race and nation,'" I explore the theme of degeneration and renewal (the idea of Jerusalem) in two novels of empire.
UTDSP, a VLIW programmable DSP processor

VLIW architectures are well-suited for implementing application-specific programmable processors because of their great scalability and modularity. VLIW architectures take advantage of not only temporal parallelism found in RISC architectures but also spatial parallelism by using multiple functional units. However, the large instruction storage and bandwidth requirements have prevented VLIW architectures from being used in cost-sensitive systems. This thesis describes a VLIW DSP processor called UTDSP, which incorporates a novel and flexible instruction packing and fetching mechanism to reduce the code size and bandwidth problems plaguing other VLIW architectures. With this scheme it is possible to actually achieve some code compression while attaining significant performance speedup over a traditional architecture. The UTDSP is flexible in that additional functional units with application-specific instructions can be easily added when required for performance with little impact on its compiler. The VLSI design and implementation of the UTDSP is presented. This implementation, consisting of five pipeline stages, is capable of executing seven instructions per cycle and provides zero-overhead hardware loops that are nestable and interruptable. A GUI-based assembly debugger and architecture simulator were implemented. The UTDSP adopts a synthesis-based design methodology and a novel hierarchical CAD flow that can significantly reduce its area.
Expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases in the hematopoietic microenvironment

Stem cells and progenitor cells within the hematopoietic microenvironment interact specifically with cell and ECM ligands present in the bone marrow. Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) are key regulators of ECM turnover. We hypothesize that MMPs and TIMPs play critical roles in regulating hematopoiesis. We analyzed the expression of functional gelatinases, (MMP-2, MMP-9) and TIMPs (TIMP-1, TIMP-2) in long-term bone marrow cultures (LTBMC) by zymography, reverse zymography and Western blotting. Bone marrow progenitor cells constitutively express MMP-9 and TIMP-2 whereas expression of MMP-2 and TIMP-1 is correlated with the growth of the stroma. Stromal cell cultures were established to study cytokine regulation of MMPs and TIMPs. MMP-9, MMP-2 and TIMP-1 expression was induced by PMA, TNF-Ã and IL-1ß yet no TIMP-2 was expressed. Combinations of PMA/TNF-Ã and GM-CSF/IL-1ß had additive effects on induction of MMP-9 expression. Tyrosine kinase inhibitors specifically inhibited cytokine-induced MMP-9, MMP-2 and TIMP-1 expression.
Economic lot scheduling for production systems subject to random failure

Two models of a single machine, multi-item production system subject to random failure will be presented. In the first part of the thesis, we develop a common cycle-based model. By applying the classical renewal theory, the formula for the long-run expected average cost per unit time is obtained for the two-item case with generally distributed time to failure and repair time. We also study the effect of random machine failure time and repair time on the optimal lot size. In the second part, another model, which is closer to the real production, is presented. Treating the process as a semi-regenerative process (SRP) and analyzing the SRP by Markov renewal theory, we get the formula for the long-run expected average cost per unit time with distributed time to failure and repair times.