20 resultados para non-reproducibility of the cross sections

em Brock University, Canada


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Charts and graphs of cross sections from Brown’s ditch culvert to the main drain, cross sections from the feeder on the road allowance between lots 26 and 27 in the 5th concession of Humberstone, Cross sections of the main drain from Lyons Creek culvert to the road allowance between lots 7 and 8 in Wainfleet and cross selections of the old ditch on the west side of the road allowance between lots 17 and 18 in the 3rd concession in Wainfleet (8 pages, hand drawn), n.d.

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Diagrams of cross sections on the Welland Railway, Port Dalhousie (4 hand-drawn diagrams), March 1860.

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Cross sections of excavation required to make a ditch on the earth side of the railroad near Port Dalhousie. This is a 12 page booklet of hand- drawn charts and diagrams which is slightly stained. Text is not affected, Mar. 1860.

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One of the fundamental problems with image processing of petrographic thin sections is that the appearance (colour I intensity) of a mineral grain will vary with the orientation of the crystal lattice to the preferred direction of the polarizing filters on a petrographic microscope. This makes it very difficult to determine grain boundaries, grain orientation and mineral species from a single captured image. To overcome this problem, the Rotating Polarizer Stage was used to replace the fixed polarizer and analyzer on a standard petrographic microscope. The Rotating Polarizer Stage rotates the polarizers while the thin section remains stationary, allowing for better data gathering possibilities. Instead of capturing a single image of a thin section, six composite data sets are created by rotating the polarizers through 900 (or 1800 if quartz c-axes measurements need to be taken) in both plane and cross polarized light. The composite data sets can be viewed as separate images and consist of the average intensity image, the maximum intensity image, the minimum intensity image, the maximum position image, the minimum position image and the gradient image. The overall strategy used by the image processing system is to gather the composite data sets, determine the grain boundaries using the gradient image, classify the different mineral species present using the minimum and maximum intensity images and then perform measurements of grain shape and, where possible, partial crystallographic orientation using the maximum intensity and maximum position images.

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Higher plants have evolved a well-conserved set of photoprotective mechanisms, collectively designated Non-Photochemical Quenching of chlorophyll fluorescence (qN), to deal with the inhibitory absorption of excess light energy by the photosystems. Their main contribution originates from safe thermal deactivation of excited states promoted by a highly-energized thylakoid membrane, detected via lumen acidification. The precise origins of this energy- or LlpH-dependent quenching (qE), arising from either decreased energy transfer efficiency in PSII antennae (~ Young & Frank, 1996; Gilmore & Yamamoto, 1992; Ruban et aI., 1992), from alternative electron transfer pathways in PSII reaction centres (~ Schreiber & Neubauer, 1990; Thompson &Brudvig, 1988; Klimov et aI., 1977), or from both (Wagner et aI., 1996; Walters & Horton, 1993), are a source of considerable controversy. In this study, the origins of qE were investigated in spinach thylakoids using a combination of fluorescence spectroscopic techniques: Pulse Amplitude Modulated (PAM) fluorimetry, pump-probe fluorimetry for the measurement of PSII absorption crosssections, and picosecond fluorescence decay curves fit to a kinetic model for PSII. Quenching by qE (,..,600/0 of maximal fluorescence, Fm) was light-induced in circulating samples and the resulting pH gradient maintained during a dark delay by the lumenacidifying capabilities of thylakoid membrane H+ ATPases. Results for qE were compared to those for the addition of a known antenna quencher, 5-hydroxy-1,4naphthoquinone (5-0H-NQ), titrated to achieve the same degree of Fm quenching as for qE. Quenching of the minimal fluorescence yield, F0' was clear (8 to 130/0) during formation of qE, indicative of classical antenna quenching (Butler, 1984), although the degree was significantly less than that achieved by addition of 5-0H-NQ. Although qE induction resulted in an overall increase in absorption cross-section, unlike the decrease expected for antenna quenchers like the quinone, a larger increase in crosssection was observed when qE induction was attempted in thylakoids with collapsed pH gradients (uncoupled by nigericin), in the absence of xanthophyll cycle operation (inhibited by DTT), or in the absence of quenching (LlpH not maintained in the dark due to omission of ATP). Fluorescence decay curves exhibited a similar disparity between qE-quenched and 5-0H-NQ-quenched thylakoids, although both sets showed accelerated kinetics in the fastest decay components at both F0 and Fm. In addition, the kinetics of dark-adapted thylakoids were nearly identical to those in qEquenched samples at F0' both accelerated in comparison with thylakoids in which the redox poise of the Oxygen-Evolving Complex was randomized by exposure to low levels of background light (which allowed appropriate comparison with F0 yields from quenched samples). When modelled with the Reversible Radical Pair model for PSII (Schatz et aI., 1988), quinone quenching could be sufficiently described by increasing only the rate constant for decay in the antenna (as in Vasil'ev et aI., 1998), whereas modelling of data from qE-quenched thylakoids required changes in both the antenna rate constant and in rate constants for the reaction centre. The clear differences between qE and 5-0H-NQ quenching demonstrated that qE could not have its origins in the antenna alone, but is rather accompanied by reaction centre quenching. Defined mechanisms of reaction centre quenching are discussed, also in relation to the observed post-quenching depression in Fm associated with photoinhibition.

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Since the first offshore Lake Erie well was drilled in 1941, the Grimsby and Thorold formations of the Cataract Group have been economically important to the oil and gas industry of Ontario. The Cataract Group provides a significant amount of Ontario's gas production primarily from wells located on Lake Erie. The Grimsby - Thorold formations are the result of nearshore estuarine processes influenced by tides on a prograding shelf and are composed of subtidal channel complexes, discrete tidal channels, mud flats and non-marine deposits. Deposition was related to a regressive - transgressive cycle associated with eustatic sea level changes caused by the melting and resurgence of continental glaciation centred in Africa in the Late Ordovician/Early Silurian. Grimsby deposition began during a regression with the deposition of subtidal channel complexes incised into the marine deposits of the Cabot Head Formation. The presence of mud drapes and mud couplets suggest that these deposits were influenced by tides. These deposits dominate the lower half of the Grimsby. Deposition continued with a change from these subtidal channel complexes to laterally migrating, discrete, shallow tidal channels and mud flats. These were in turn overlain by the non-marine deposits of the Thorold Formation. Grimsby - Thorold deposition ended with a major transgression replacing siliciclastic deposition with primarily carbonate deposition. Sediment was sourced from the east and southeast and associated with a continuation of the Taconic Orogeny into the Early Silurian. The fluvial head of the estuary prograded from a shoreline that was located in western New York and western Pennsylvania running NNE-SSW and then turning NW-SE and paralleling the present day Lake Erie shoreline. iii The facies attributed to the Grimsby - Thorold formations can be ascribed to the three zones within the tripartite zonation suggested by Dalrymple et ale (1992) for estuaries, that is, a marine-dominated facies, a mixed energy facies, and a facies that is dominated by fluvial processes. Also, sediments within the Grimsby - Thorold are commonly fining upwards sequences which are common in estuarine settings whereas deltaic deposits are normally composed of coarsening upwards sequences in a vertical wedge shape with coarser material near the head. The only coarsening observed was in the Thorold Formation and attributed to non-marine deposition by palynological evidence. The presence of a lag deposit at the base of the sediments of the Grimsby Thorold formations suggests that they were incised into the Cabot Head Formation. Further, the thickness of Early Silurian sediments located between the top of the Queenston Formation, where Early Silurian sedimentation began, to the top of the Reynales - Irondequoit formation are constant whether the Grimsby - Thorold formations are present or not. Also, cross-sections using a sand body located in the Cabot Head Formation for correlation further imply that the Grimsby Formation has been incised into the previous deposits of the Cabot Head.

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The optical cross section of PS I in whole cells of Porphyridium cruentum (UTEX 161), held in either state 1 or state 2, was determined by measuring the change in absorbance at 820nm, an indication of P700+; the X-section of PS2 was determined by measuring the variable fluorescence, (Fv-Fo)/Fo, from PS2. Both cross-sections were 7 determined by fitting Poisson distribution equations to the light saturation curves obtained with single turnover laser flashes which varied in intensity from zero to a level where maximum yield occurred. Flash wavelengths of 574nm, 626nm, and 668nm were used, energy absorbed by PBS, by PBS and chla, and by chla respectively. There were two populations of both PSi and PS2. A fraction of PSi is associated with PBS, and a fraction of PS2 is free from PBS. On the transition S1->S2, only with PBS-absorbed energy (574nm) did the average X-section of PSi increase (27%), and that of PS2 decrease (40%). The fraction of PSi associated with PBS decreased, from 0.65 to 0.35, and the Xsection of this associated PS 1 increased, from 135±65 A2 to 400±300A2. The cross section of PS2 associated with PBS decreased from 150±50 A2 to 85±45 A2, but the fraction of PS2 associated with PBS, approximately 0.75, did not change significantly. The increase in PSi cross section could not be completely accounted for by postulating that several PSi are associated with a single PBS and that in the transition to state2, fewer PSi share the same number of PBS, resulting in a larger X-section. It is postulated that small changes occur in the attachment of PS2 to PBS causing energy to be diverted to the attached PSi. These experiments support neither the mobile-PBS model of state transitions nor that of spillover. From cross section changes there was no evidence of energy transfer from PS2 to PSi with 668nm light. The decrease in PS2 fluorescence which occurred at this wavelength cannot be explained by energy transfer; another explanation must be sought. No explanation was found for an observed decrease in PSi yield at high flash intensities.

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The Dummer Complex extends 180 km along the Precambrian - Paleozoic contact from Tamworth to Lake Simcoe. It is composed of coarse, angular Paleozoic clasts in discontinuous, pitted, hummocky deposits. Deposits are usually separated by bare or boulder strewn bedrock, but have been found in the southern drumlinized till sheet. Dummer Complex deposits show rough alignment with ice-flow. Eskers cross-cut many of the deposits. Dummer sediment subfacies are defined on the basis of dominant coarse grain size and lithology, which relate directly to the underlying Paleozoic formation. Three subglacial tills are identified based on the degree of comminution and distance of transport; the immature facies of the Dummer Complex; the mature facies of the drumlinized till sheet and; the submature facies which is transitional. Carbonate geochemistry was used for till-bedrock correlation in various grain sizes. Of the 3 Paleozoic formations underlying the Dummer Complex, the Gull River Fm. is geochemically distinctive from the Bobcaygeon and Verulam Formations using Ca, Mg, Sr, Cu, Mn, Fe and Na. The Bobcaygeon Fm. and Verulam Fm. can be differentiated using Ca and the Sr/Ca ratio. The immature facies from 1.0 phi and finer is dominated by the non-carbonate, long distance transported component which decreases slightly downice. The submature till facies contains more long distance material than the immature facies. Sr and Mn can be used to correlate the Gull River immature till facies to the underlying bedrock the other subfacies could not be distinguished from each other or their respective source formation. This method proved to be ineffective for sediments with greater than 35% non-carbonate component, due to leaching of elements by the dissolving acid.The Dummer Complex is produced subglacially , as the compressional ice encounters the permeable Paleozoic carbonates. The increased shear strength of the ice and pore pressures in the carbonates results in the basal ice zones becoming debris ladden. Cleaner ice overrides the basal debris . laden dead ice which then acts as the glacier bed. During retreat, the Simcoe lobe stagnates as flow is cut-off by the Algonquin Highlands.

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This study examined students considered at risk of non-completion of their Ontario Secondary School Diploma and aimed to offer insight into the questions, "What factors currently lead to school disconnect" and "How can these factors be addressed?" Eight students currently enrolled in an alternative learning environment participated in the study. Each was asked to take part in two, digitally recorded interviews that were subsequently transcribed by the researcher. The data were then coded and analysed according to specific themes: obstacles, empowerment, goals, views about success, opinions of school, and power of the teacher. From these themes, three broad focus areas emerged that were used to keep the data analysis focused: worldview, school effects, and self-image. Variances between the data collected and ideas presented in the current literature were highlighted as a reminder that when dealing with a human population, we cannot rely on textbook definitions and theory alone.

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The CATCH Kids Club (CKC) is an after-school intervention that has attempted to address the growing obesity and physical inactivity concerns publicized in current literature. Using Self-Determination Theory (SDT: Deci & Ryan, 1985) perspective, this study's main research objective was to assess, while controlling for gender and age, i f there were significant differences between the treatment (CKC program participants) and control (non- eKC) groups on their perceptions of need satisfaction, intrinsic motivation and optimal challenge after four months of participation and after eight months of participation. For this study, data were collected from 79 participants with a mean age of9.3, using the Situational Affective State Questionnaire (SASQ: Mandigo et aI., 2008). In order to determine the common factors present in the data, a principal component analysis was conducted. The analysis resulted in an appropriate three-factor solution, with 14 items loading onto the three factors identified as autonomy, competence and intrinsic motivation. Initially, a multiple analysis of co-variance (MANCOY A) was conducted and found no significant differences or effects (p> 0.05). To further assess the differences between groups, six analyses of co-variance (ANeOY As) were conducted, which also found no significant differences (p >0 .025). These findings suggest that the eKC program is able to maintain the se1fdetermined motivational experiences of its participants, and does not thwart need satisfaction or self-determined motivation through its programming. However, the literature suggests that the CKe program and other P A interventions could be further improved by fostering participants' self-determined motivational experiences, which can lead to the persistence of healthy PA behaviours (Kilpatrick, Hebert & Jacobsen, 2002).

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A substantial research literature exists regarding the psychopathy construct in forensic populations, but more recently, the construct has been extended to non-clinical populations. The purpose of the present dissertation was to investigate the content and the correlates of the psychopathy construct, with a particular focus on addressing gaps and controversies in the literature. In Study 1, the role of low anxiety in psychopathy was investigated, as some authors have proposed that low anxiety is integral to the psychopathy construct. Participants (n = 346) responded to two self-report psychopathy scales, the SRP-III and the PPI-R, as well as measures of temperament, personality, and antisociality. Of particular interest was the PPI-R Stress Immunity sub scale, which represents low anxiety content. I t was found that Stress Immunity was not correlated with SRP-III psychopathy, nor did it share common personality or temperament correlates or contribute to the prediction of anti sociality. From Study 1, it was concluded that it was unlikely that low anxiety is a central feature of the psychopathy construct. In Study 2, the relationship between SRP-III psychopathy and Ability Emotional Intelligence (Le., Emotional Intelligence measured as an ability, rather than as a self-report personality trait-like characteristic) was investigated, to determine whether psychopathy is be s t seen as a syndrome characterized by emotional deficits or by the ability to skillfully manipulate and prey upon the others' emotions. A negative correlation between the two constructs was found, suggesting that psychopathy is best characterized by deficits in perceiving, facilitating, managing, and understanding emotions. In Study 3, sex differences in the sexual behavior (i.e., promiscuity, age of first sexual behaviors, extradyadic sexual relations) and appearance-related esteem (i.e., body shame,appearance anxiety, self-esteem) correlates of SRP-III psychopathy were investigated. The sexual behavior correlates of psychopathy were quite similar for men and women, but the esteem correlates were very different, such that high psychopathy in men was related to high esteem, whereas high psychopathy in women was generally related to low esteem. This sex difference was difficult to interpret in that it was not mediated by sexual behavior, suggesting that further exploration of this topic is warranted. Together, these three studies contribute to our understanding of non-clinical psychopathy, indicating that low anxiety is likely not part of the construct, that psychopathy is related to low levels of ability in Emotional Intelligence, and that psychopathy is an important predictor of behavior, ability, and beliefs and feelings about the self

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The current set of studies was conducted to examine the cross-race effect (CRE), a phenomenon commonly found in the face perception literature. The CRE is evident when participants display better own-race face recognition accuracy than other-race recognition accuracy (e.g. Ackerman et al., 2006). Typically the cross-race effect is attributed to perceptual expertise, (i.e., other-race faces are processed less holistically; Michel, Rossion, Han, Chung & Caldara, 2006), and the social cognitive model (i.e., other-race faces are processed at the categorical level by virtue of being an out-group member; Hugenberg, Young, Bernstein, & Sacco, 2010). These effects may be mediated by differential attention. I investigated whether other-race faces are disregarded and, consequently, not remembered as accurately as own-race (in-group) faces. In Experiment 1, I examined how the magnitude of the CRE differed when participants learned individual faces sequentially versus when they learned multiple faces simultaneously in arrays comprising faces and objects. I also examined how the CRE differed when participants recognized individual faces presented sequentially versus in arrays of eight faces. Participants’ recognition accuracy was better for own-race faces than other-race faces regardless of familiarization method. However, the difference between own- and other-race accuracy was larger when faces were familiarized sequentially in comparison to familiarization with arrays. Participants’ response patterns during testing differed depending on the combination of familiarization and testing method. Participants had more false alarms for other-race faces than own-race faces if they learned faces sequentially (regardless of testing strategy); if participants learned faces in arrays, they had more false alarms for other-race faces than own-races faces if ii i they were tested with sequentially presented faces. These results are consistent with the perceptual expertise model in that participants were better able to use the full two seconds in the sequential task for own-race faces, but not for other-race faces. The purpose of Experiment 2 was to examine participants’ attentional allocation in complex scenes. Participants were shown scenes comprising people in real places, but the head stimuli used in Experiment 1 were superimposed onto the bodies in each scene. Using a Tobii eyetracker, participants’ looking time for both own- and other-race faces was evaluated to determine whether participants looked longer at own-race faces and whether individual differences in looking time correlated with individual differences in recognition accuracy. The results of this experiment demonstrated that although own-race faces were preferentially attended to in comparison to other-race faces, individual differences in looking time biases towards own-race faces did not correlate with individual differences in own-race recognition advantages. These results are also consistent with perceptual expertise, as it seems that the role of attentional biases towards own-race faces is independent of the cognitive processing that occurs for own-race faces. All together, these results have implications for face perception tasks that are performed in the lab, how accurate people may be when remembering faces in the real world, and the accuracy and patterns of errors in eyewitness testimony.

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The King’s Royal Regiment of New York was a Loyalist regiment that served on the Canadian frontier during the American Revolutionary War. The regiment was commanded by Sir John Johnson, who recruited members from the settlers on his estates in the Mohawk Valley. After the War, the two battalions of the regiment were disbanded. The First Battalion settled on the north shore of the St. Lawrence, while the Second Battalion settled by the Bay of Quinte.

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The goal of most clustering algorithms is to find the optimal number of clusters (i.e. fewest number of clusters). However, analysis of molecular conformations of biological macromolecules obtained from computer simulations may benefit from a larger array of clusters. The Self-Organizing Map (SOM) clustering method has the advantage of generating large numbers of clusters, but often gives ambiguous results. In this work, SOMs have been shown to be reproducible when the same conformational dataset is independently clustered multiple times (~100), with the help of the Cramérs V-index (C_v). The ability of C_v to determine which SOMs are reproduced is generalizable across different SOM source codes. The conformational ensembles produced from MD (molecular dynamics) and REMD (replica exchange molecular dynamics) simulations of the penta peptide Met-enkephalin (MET) and the 34 amino acid protein human Parathyroid Hormone (hPTH) were used to evaluate SOM reproducibility. The training length for the SOM has a huge impact on the reproducibility. Analysis of MET conformational data definitively determined that toroidal SOMs cluster data better than bordered maps due to the fact that toroidal maps do not have an edge effect. For the source code from MATLAB, it was determined that the learning rate function should be LINEAR with an initial learning rate factor of 0.05 and the SOM should be trained by a sequential algorithm. The trained SOMs can be used as a supervised classification for another dataset. The toroidal 10×10 hexagonal SOMs produced from the MATLAB program for hPTH conformational data produced three sets of reproducible clusters (27%, 15%, and 13% of 100 independent runs) which find similar partitionings to those of smaller 6×6 SOMs. The χ^2 values produced as part of the C_v calculation were used to locate clusters with identical conformational memberships on independently trained SOMs, even those with different dimensions. The χ^2 values could relate the different SOM partitionings to each other.