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Forward in situ combustion in fractured heavy oil reservoirsJavanmardi, Gholam Reza January 1992 (has links)
No description available.
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The separation and immobilisation of a yeast intracellular enzymeSadler, Andrew Michael January 1988 (has links)
The aim of this work was to investigate the problems involved in production and separation of a yeast microsomal enzyme, cytochrome P450. Immobilisation of the microsomal preparation, and utilisation of the immobilised system for the removal of polycyclic aromatic hydrocarbons, particularly the carcinogen benzo(a)pyrene [B(a)P], from aqueous systems was also investigated. High recoveries of the microsomal enzyme were obtained using rapid, low-speed centrifugation (5 minutes, 3000xg) by prior precipitation with a non-ionic polymer, polyethylene glycol (PEG). PEG was found to effectively replace centrifugal acceleration. A semi-empirical mathematical model of the process based on the size distribution of the agglomerates formed and the proportion of the agglomerates sedimented by centrfugation was developed. The effect of PEG was consistent with its increasing the mean effective diameter of protein agglomerates in proportion to PEG concentration to an exponent of 0.619 and with its increasing the spread of the size distribution in proportion to the mean effective agglomerate diameter. Binding spectra studies established that B(a)P binds to the active site of yeast cytochrome P450 and is unaffected by PEG. The B(a)P assay by fluorescence following hexane extraction was also unaffected by PEG. The stability of the microsomal cytochrome P450 preparation at different temperatures was investigated. The enzyme half-life was 66 minutes at 37° and was also unaffected by PEG. The enzyme preparation was satisfactorily immoblilsed by encapsulation in calcium alginate gel and enzyme distribution profiles were determined in sections of alginate stained with coomasie blue by a novel technique using a scanning optical densitometer, Diffusivity coefficients of B(a)P and NADP in alginate gel beads were determined as 7.5 and 2.5 x 10[-10] m[2]/S, respectively by the Tanaka method, fitting solute depletion profiles to Crank's theoretical model. The microsomal enzyme preparation immobilised in alginate beads was used to remove B(a)P from aqueous solution. B(a)P removal was shown to be by a non-specific affinity absorption mechanism and the removal profile was found to correspond well to a theoretical model of a diffusion-reaction system, for an affinity ligand system. The activaiton energy for deactivation of microsomal P450 was measured as 33.56kJ/mole.
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Observer Retaliation: How Apology Components Affect Observing Customers' Negative Word-of-Mouth and Patronage IntentionsMcClure, Todd 01 December 2016 (has links)
An apology is a standard expression often articulated by someone who has wronged another. Prior service failure and recovery literature has explored the impact uncivil acts and subsequent recovery efforts in a service environment, although this research has been focused on the involved customer’s perceptions and retaliatory intentions. In a service environment, third party customers are often able to observe the interactions (both positive and negative) of others. Prior literature has yet to examine the influence of each characteristic of an apology on an observing customer’s retaliatory intentions. To address this gap in the literature, the present research examines how apologies influence observing customers’ negative word-of-mouth and return intentions. Four apology components (timeliness, accepting responsibility, initiation, and remorse) were examined. In addition, three blocking variables (gender, moral identity, and self-construal) are included in order to empirically examine whether any of the apology components had a unique effect on specific groups of individuals compared to others.
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Development and mathematical modelling of affinity system based on novel matrixOnwuasoanya, Daniel I. January 1987 (has links)
No description available.
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Chemical and Microbial Processes for Rhodium RecoveryZhu, Kechen, Zhu, Kechen January 2017 (has links)
This is the first report that demonstrates the ability of anaerobic methanogenic granular sludge to reduce Rh(III) to Rh(0). Recovery of rhodium(Rh) during anaerobic incubations under abiotic and biotic condition with different electron donors was studied. H2 and formate reduced Rh(III) to Rh(0) nanoparticles(NPs) in the absence of microorganisms. However, the presence of microorganism was crucial for Rh(III) reduction with ethanol. Results of X-ray powder diffraction (XRD) and transmission electron microscopy (TEM) confirmed the formation of Rh(0) NPs and indicated the localization and morphology of the formed Rh(0) NPs varied with electron donor utilized. Rh(III) reduction with H2 and ethanol obeyed 1st order kinetics. Rh(III) caused a moderate inhibition to methanogenesis. Rh(III) reduction often ceased before coming to completion but this effect is not due to unfavorable thermodynamics. A hypothesis was developed which ascribes the biological reduction of Rh(III) with ethanol as being due to the biological formation of H2 (that subsequently chemically reacts with Rh). The results obtained indicate the potential of utilizing anaerobic granular sludge bioreactor technology as a practical and promising option in Rh(III) recovery.
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Experimental observation and measurement of the flow of water and oil through polymer gelsAl-Sharji, Hamed Hamoud January 2000 (has links)
No description available.
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Multiphase flow of oil, water and gas in horizontal pipesHall, Andrew Robert William January 1992 (has links)
No description available.
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Evaluating the Functional Role of Enhancing Progenitor Cell Survival Following Stroke RecoveryCeizar, Maheen January 2017 (has links)
Stroke is the leading cause of long-term neurological disability worldwide, signifying the need for viable therapeutic options. Pre-clinical and post-mortem stroke studies have demonstrated that stroke increases the number of newborn progenitor cells (PCs) in the adult brain that can migrate to the site of injury. While there is a positive correlation between increasing neurogenesis and improvements in stroke recovery, methods used to increase PCs and neurogenesis also alter many other forms of plasticity, making it difficult to determine the function of PCs per se. To investigate whether specifically enhancing PC survival is sufficient to improve recovery, the iBax transgenic mouse model was used to remove the pro-apoptotic gene Bax inducibly from nestin-expressing PCs either before or after focal strokes induced by photothrombosis. Increasing PC survival before or after stroke in the iBax mice increased the number of PCs in the peri-infarct region. Interestingly, the majority of the cells that migrated to the peri-infarct region expressed the glial fibrillary acidic protein (GFAP) which is found in astrocytes when Bax was removed prior to stroke, yet when Bax was removed after stroke the majority of the cells expressed doublecortin (DCX) which is expressed in neuroblasts. Irrespective of this significant increase in the different populations of surviving PCs following stroke, there was no change in long-term behavioural deficits on the adhesive removal, horizontal ladder, and cylinder tasks up to 90 days post stroke. Additionally, enhancing PC survival before or after stroke resulted in a significant increase in adult-generated neurons within the dentate gyrus, which was associated with a modest change in spatial learning on the Barnes maze. Together, these experiments suggest strategies that enhance the survival of the PCs by preventing cell death will, by themselves, be insufficient to promote sensorimotor recovery following stroke.
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Understanding recovery in psychosisLaw, Heather Louise January 2014 (has links)
This thesis explored conceptualisations of recovery, associated psychological factors and predictors, measurement of subjective recovery, and attitudes towards recovery. A multi-method approach was utilised, including reviewing evidence from the existing literature, cross-sectional, survey and longitudinal designs, and a computer based implicit association task. Chapter 1 provided a review of the literature, followed by an overview of the methodology employed throughout this thesis in chapter 2. Chapter 3 (study 1) included a user informed review of existing recovery measures. The Recovery Assessment Scale appeared to be the most valid and acceptable measure currently in use, although the Questionnaire about the Process of Recovery (QPR) received particularly positive feedback from service users, but lacked further psychometric validation. Consequently, chapter 4 (study 2, N=335) went on to explore the psychometric properties of the QPR. Exploratory factor analysis suggested a one factor model with high internal consistency, test re-test reliability and convergent validity. Recommendations for the use of the QPR in routine clinical practice was discussed. Chapter 5 (study 3, N=381) utilised the Delphi method to consult a large sample of service users about their views on recovery. A high level of consensus (>80%) was reached for a number of items on defining recovery, factors which help and hinder recovery and factors which show recovery. Implications for clinical practice and future research are discussed. Chapter 6 (study 4, N=110) examined longitudinal predictors of recovery. Negative emotion, positive self-esteem, hopelessness, and to a lesser extent symptoms and functioning predicted subjective recovery. Psychosocial factors and negative emotion appear to be the strongest longitudinal predictors of subjective recovery. Chapter 7 (study 5, N=146) used an online survey and computer task to explore attitudes towards recovery in health professionals and the general public. Explicit attitudes towards recovery were generally positive, with health professionals having significantly more positive attitudes than the general public group. Positive attitudes towards recovery were predicted by greater knowledge of recovery and a preference for psychosocial causal models of psychosis. Implications for focussing on psychosocial causal explanations in recovery training and awareness programmes for health professionals and the general public are discussed. This thesis has advanced our understanding of recovery by reaching consensus about what recovery means to individuals with experiences of psychosis, evaluating tools for measuring recovery and determining some of the key psychological processes and predictors of recovery, including causal beliefs, locus of control and negative emotion. These findings appear to fall into four main themes: conceptualising and defining recovery, measurement of recovery, relationships between psychological processes and recovery, and facilitating recovery. Further research is needed to explore recovery across the continuum of psychosis and investigate recovery focussed interventions which target the key psychological processes identified throughout this thesis.
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The Effects of Remote Post-Exercise Ischemic Conditioning on Recovery from Strenuous ExerciseLillquist, Thomas Jonathan January 2020 (has links)
BACKGROUND: Strategic limb occlusion applied after exercise (PEIC) may expedite recovery, not just in directly affected tissue, but over the entire body via circulating factors. METHODS: Twenty active college-age males took part in a single-blind randomized crossover design. Participants underwent intervention and SHAM treatments after strenuous exercise sessions. Peak Torque production and soreness measures were gathered directly before and 24-hours after two exercise sessions. STATISTICAL ANALYSES: A 2 x 2 repeated measures analysis of variance with sidak corrections (significance of p<0.05) was used to analyze peak torque and VAS scores. RESULTS: Significance was not observed between any associated pre- and post-peak torque test (p > 0.05). Post-treatment VAS scores were statistically higher than pre-treatment for all conditions except pre-and post-intervention in the direct leg (P = 0.096). DISCUSSION: The application of PEIC was not associated with any significant differences in peak torque production or soreness measures.
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