327 research outputs found
Reuse of hybrid car power systems
No full textThesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.Cataloged from PDF version of thesis.Includes bibliographical references (page 37).Used hybrid car power systems are inexpensive and capable of tens of kilowatts of power throughput. This paper documents a process for using the second generation Toyota Prius inverter module to drive a three phase permanent magnet synchronous motor/generator from Ford hybrid vehicle. A lightweight housing and a rotor position sensor for the motor/generator are constructed to allow it to be used outside of the original bulky transaxle. Field oriented control is implemented on a microcontroller which interfaces with the motor/generator and the Prius inverter module. The motor, inverter, and controller are installed on a demonstration vehicle for the purpose of load testing.by Nicholas Kirkby.S.B
The clergy of the deaneries of Rochester and mailing in the diocese of Rochester, c. 1770 – 1870
No full textThis is a study of the concerns and life - style of the clergy of the established Church in two Kent Deaneries throughout the hundred year period, 1770 -1870. How far, it is considered, were episcopal hopes, which were expressed in the Charges of Bishop and Archdeacon, fulfilled in the parishes, especially in the matters of residence and education. The extent of non-residence is deduced from. such evidence as is available for the earlier part of the period and after 1830 from Visitation and other returns. The provision of Sunday Schools is used as an example of clerical response to a diocesan policy in the field of education. The exercise of patronage, residence, plurality, the length ofincumbencies, the employment of curates and their prospects, are looked at throughout the period. The provision of new churches, agrarian unrest, tithe and clerical emoluments, church rate, relationship with dissent, worship provision , the visitation process, the clergyman's role in society, the differing demands of town ministry and rural ministry are examined as events bring them to the fore . The priorities of successive bishops are noted and the lives of sample clergymen are taken for each period, both to flesh-out the statistics and to illustrate the evolving pattern of ministry
Investigating the role of endothelin receptor subtypes in the response to vascular injury
No full textNeointimal hyperplasia, the proliferative growth of the innermost layer of the blood
vessel wall, is a key process in the response to vascular injury, underlying conditions
such as post-interventional restenosis and vein/arterial graft disease. One of the many
mediators implicated in this process is endothelin-1 (ET-1), a potent vasoconstrictor
with pro-inflammatory and pro-mitogenic actions, which acts through ETA and ETB
receptor subtypes. It is well established that ET-1 increases, and ETA blockade
reduces, neointima formation following vascular injury. The role of ETB is less clear
because these receptors mediate potentially beneficial actions in endothelial cells
(EC; such as nitric oxide production, and ET-1 clearance) but detrimental effects
elsewhere (such as vascular smooth muscle) and it has been recently reported that
non-cell-specific ETB deficiency is associated with increased neointimal lesion size
following injury. The work described in this thesis addressed the hypothesis that
endogenous ET-1 contributes to neointimal hyperplasia by activation of the ETA
receptor, and that this action is moderated by concurrent activation of the ETB
receptor expressed in EC.
The role of ET receptors in neointimal lesion development was assessed using two
models of femoral arterial injury in the mouse: (i) an established method of intraluminal
wire-injury, and (ii) adaptation of a model of ligation injury that induces
robust neointimal lesion formation without physical damage to the endothelium.
Lesion development was assessed using standard histological techniques and this
was augmented by development of quantitative optical projection tomography (OPT)
to allow three-dimensional analysis of lesions.
The role of ETA and ETB receptors in these models was addressed using suitable
pharmacological ET receptor antagonists. Following wire-injury, selective ETB
blockade (A192621; 30mg.kg-1.day-1; 35 days) increased lesion size and blood
pressure without significant altering lesion composition. In contrast, selective ETA
blockade (atrasentan; 10mg.kg-1.day-1; 35 days) reduced lesion size and blood
pressure. Combined ETA+ETB antagonism had no effect on lesion size, despite reducing blood pressure, and reducing collagen content of the lesions. In the ligation
model, neither ETA selective, ETB selective nor ETA+ETB blockade altered lesion
size as assessed by standard histology but analysis by OPT indicated that ETA
blockade, with or without concurrent ETB blockade, reduced lesion volume.
The influence of ETB receptors expressed by ECs on lesion formation was addressed
using EC-specific ETB knockout mice. Small vessel myography indicated that
endothelium-dependent relaxation was unaltered in femoral arteries from these mice.
In addition, no effect on lesion size or rate of development was observed in either
wire- or ligation-injury models of neointima formation (although subtle effects on
lesion and medial composition were apparent after intra-luminal injury).
These results indicate that ETB receptor activation can moderate the detrimental
actions of the ETA receptor on neointimal lesion progression, and that this role is
dependent on the mode of vascular injury. Furthermore, in this setting, this beneficial
action is not primarily mediated by ETB expressed by EC, suggesting that ETB in
other cell types can reduce lesion development through another, unidentified
mechanism. Therefore, while both ETA selective and non-selective ETA/B
antagonists are currently in clinical use, in conditions where similar arterial
remodelling processes occur, selective ETA receptor antagonists might be preferred
minpot-toolkit
No full textMaintenance and Update Frequency: unknownStatement: <div>A Python repository adapted from an earlier "mineral-stats-toolkit" (Kirkby, 2022) to generalize analysis and enable mineral potential mapping.</div><b>Purpose</b><br/>A software repository to facilitate mineral systems inference and support mineral potential mapping.<div>The mineral potential toolkit (aka minpot-toolkit) provides tools to facilitate mineral potential analysis, from spatial associations to feature engineering and fully integrated mineral potential mapping.</div>
Subclinical hyperthyroidism in cats: A spontaneous model of subclinical toxic nodular goiter in humans?
No full textIntroduction and Objectives: Hyperthyroidism in cats, caused by nodular hyperplasia or adenomas, is clinically and histologically similar to toxic nodular goiter in humans. Subclinical hyperthyroidism in humans is defined as low thyrotropin (TSH) in conjunction with within-reference-range thyroid hormone concentrations, but has not previously been defined in cats. The objective of this study was to test the hypothesis that euthyroid senior cats with low TSH have histological evidence of thyroid nodular hyperplasia and/or adenoma. Design: Thyroid glands removed postmortem from four groups of cats (n = 73) were examined histologically and scored in a blinded fashion. Clinically euthyroid senior (> 7 years) cats were divided into two groups dependent on their TSH concentration-TSH below the limit of quantification (LOQ) of the assay (= 0.03 ng/mL; n = 31; DetectableTSH group)-using archived plasma samples, collected 0-6 months antemortem. Thyroids were also scored for two control groups: Young group (cats < 6 years old; n = 13) and Hyperthyroid group (clinically and biochemically hyperthyroid cats; n = 14). Main outcome: Cats in the UndetectableTSH group had a higher frequency of nodules, a greater percentage of abnormal thyroid tissue, and a higher overall histopathological grade than cats with detectable TSH had. Conclusion: Euthyroid (as defined by total thyroxine) senior cats with low TSH are likely to have histological evidence of nodular thyroid disease, and such cats could be considered to be subclinically hyperthyroid
Studying COX-2 in the cardiovascular system using a transcriptomic approach
No full textAt the time of starting my thesis there were no agreed mechanisms that could explain how cyclooxygenase (COX)-2 protects the cardiovascular system and no ‘hypothesis generating’ approaches done to try to find new answers. I have used transcriptomics, to come up with targets for this problem. I used microarray and RNA-seq on the following experimental models; (i) tissue from COX-1/COX-2 knockout mice, (ii) wildtype mice treated with the COX-2 inhibitor paracoxib and (iii) whole blood from healthy male volunteers after taking the COX-2 inhibitor celecoxib. Transcriptomic data was also analysed from online databases including (i) Open TG-GATEs and (ii) Human Protein Atlas. Altered transcriprt lists generated using GeneSpring and StrandNGS where analysed using manual curation, g:Profiler and GeneOntology.org databases and using Gene Set Enrichment Analysis. No transcripts were altered in aorta, heart, kidney, blood or brain from COX-1 knock out mice but >260 transcripts were altered (>1.5 fold) in the renal medulla of COX-2 knockout mice or wildtype mice where COX-2 was blocked with paracoxib with expression of four cardiovascular genes, namely, Agxt2, Edn1, Cd34 and Ptgds being similarly altered in both approaches. Transcripts were also altered in blood of humans taking celecoxib or COX-2 knockout mice, although in blood it was transcripts associated with inflammation and interferon pathways that came up. As an unexpected observation, it was found that expression of the oncogene Rgl1 was down regulated in all tissues from the COX-2 knockout mice. Since drugs that block COX-2 also prevent cancer the Rgl1 hit was explored using human cancer cells.
This work helps us understand new ways that COX-2 protects the cardiovascular system and causes cancer. Finally, after more tests, the pathways I found could be used to help identify and treat people at risk of having heart attacks when they take pain killers that work by blocking COX-2.Open Acces
Online exposure for spider fear: Treatment completion and habituation outcomes
No full textThis research aimed to investigate habituation to spider images during an online exposure treatment (www.feardrop.com) among participants with a high fear of spiders. Participants (N = 392) undertook a 10-stage online exposure treatment with a stage length of either 180 or 360 seconds. Four Subjective Units of Distress Scale (SUDS) ratings were taken throughout each stage. Treatment completion was found to be a significant challenge, with less than one-third (30%) completing at least one stage of the program. Those in the shorter stage length condition were significantly more likely to complete the first stage relative to those in the longer stage length condition (43% vs. 16%). SUDS ratings decreased significantly across time at Stage 1, suggesting habituation of self-reported anxiety and there was an overall reduction in SUDS ratings at the second relative to the first stage, suggesting generalisation of habituation. The greatest habituation was observed among those with high anticipatory anxiety (pre-exposure SUDS rating), high total exposure time, and younger age. There was preliminary evidence for improvement in symptoms of spider fear at post-treatment. Directions for future research include strategies to facilitate treatment completion, evaluation of treatment outcomes, and expansion to include a range of specific fears. Author(s): Allison J. Matthews 1 * | Joel D. Scanlan 2 | Ken C. Kirkby
- …
