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1
Hand, C. W. "Studies on the human pharmacology of opiates." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379946.
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Blackburn, Thomas P. "Renal, vascular and endocrine effects of Kappa opioid agonists." Thesis, University of Manchester, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.237570.
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Park, Sung Jun. "Social facilitation effects of virtual humans." Thesis, Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-07102006-132005/.
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Gold, Ann Elizabeth. "Cerebral effects of hypoglycaemia in humans." Thesis, University of Edinburgh, 1994. http://hdl.handle.net/1842/19801.
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The effect of acute insulin-induced hypoglycaemia on cognitive function in humans was examined. The principal studies were performed: i) - to examine whether cerebral adaptation to acute neuroglycopenia occurs in normal subjects, ii) - to examine whether the degree of impairment of cognitive function during acute neuroglycopenia is related to the level of cognitive ability of the subject and iii) - to establish whether patients with insulin-treated diabetes, who have impaired awareness of hypoglycaemia exhibit a more severe degree of cognitive impairment during modest hypoglycaemia. In addition to cognitive function testing in patients with impaired awareness, studies of cerebral blood flow during hypoglycaemia were undertaken using Single Photon Emission Tomography (SPET). Mood changes during acute hypoglycaemia were also examined in non-diabetic subjects. During 60 minutes of exposure to moderate hypoglycaemia there was no evidence of short term cerebral adaptation to neuroglycopenia in normal subjects. Cognitive ability did appear to have some influence on cognitive dysfunction during hypoglycaemia: those subjects of lower cognitive ability appeared to suffer a smaller degree of cognitive dysfunction during hypoglycaemia. During acute hypoglycaemia subjects were observed to have marked changes in mood: there was a decrease in hedonic tone, an increase in tense arousal and a decrease in energetic arousal. Diabetic patients with impaired awareness of hypoglycaemia suffered greater and more prolonged cognitive dysfunction during hypoglycaemia than patients with normal awareness.
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Hall, Chris. "An investigation of the effects of opiate withdrawal syndrome on interrogative suggestibility." Thesis, University of Surrey, 1998. http://epubs.surrey.ac.uk/901/.
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Yubero, Lahoz Samanta 1985. "MDMA pharmacology in humans and serotonergic effects." Doctoral thesis, Universitat Pompeu Fabra, 2013. http://hdl.handle.net/10803/145481.
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3,4-methylenedioxymethamphetamine (MDMA, ecstasy) is one of the most abused recreational
drugs in the world. It has been extensively reported that this drug inhibits its own metabolism by
inhibiting a polymorphic liver enzyme, CYP2D6, which is responsible for the clearance of one
quarter of drugs used in therapeutics. This phenomenon has important clinical implications,
since MDMA users display a higher prevalence of psychopathology, particularly of mood
disorders, compared to control population. Importantly, these psychiatric diseases are treated
with drugs most of them substrate of this enzyme. In addition, it is not elucidated how MDMA
is still metabolically cleared even after repeated drug doses. Therefore, the first part of this
thesis was focused on studying the metabolic autoinhibition by MDMA assessing several liver
enzyme activities in men and women.
Although MDMA pharmacology is well established, is it still not clear which is the mechanism
of action of the drug. MDMA interacts with the serotonergic system at several levels, but
nowadays is technically difficult to study the serotonergic function in living human brain.
Imaging methods are limited by a number of factors. Thus, it would be advantageous to have a
reliable peripheral index of the serotonergic activity in the blood. The second part of this thesis
presents the development of several approaches aimed to assess whether the serotonin
transporter in platelets can be used as a peripheral biomarker for central serotonergic activity,
and determine if it plays any role in drug mechanism of action.La 3,4-metilendioximetanfetamina (MDMA, èxtasi) és una de les drogues més consumides al món. Aquesta droga inhibeix el seu propi metabolisme, inhibint un enzim polimòrfic del fetge, el CYP2D6, que és el responsable de l’eliminació d’una quarta part dels medicaments. Aquest fet té implicacions clíniques rellevants, ja que els consumidors de MDMA presenten una prevalença de psicopatologia més alta respecte a la població no consumidora, i moltes de la patologies psiquiàtriques es tracten amb fàrmacs substrats d’aquest enzim. A més, encara no s’ha discernit com aquesta droga pot ser eliminada de l’organisme, inclús després d’haver-ne consumit dosis de manera repetida. Així doncs, la primera part d’aquesta tesi es centra en estudiar l’autoinhibició de la MDMA determinant l’activitat de diferents enzims del fetge, en homes i dones. Encara que la farmacologia de la MDMA està descrita a fons, no està del tot clar quin és el seu mecanisme d’acció. La MDMA interactua amb el sistema serotonèrgic de diverses maneres, però avui en dia és molt difícil estudiar tècnicament el sistema serotonèrgic en el cervell humà. Les tècniques d’imatge estan limitades per molts factors, i per tant, seria molt útil tenir un índex perifèric a la sang de l’activitat serotonèrgica al sistema nerviós central. La segona part d’aquest tesi s’enfoca en el desenvolupament de tècniques per determinar a diferents nivells si el transportador de la serotonina a les plaquetes podria ser un bon biomarcador perifèric de la seva activitat al cervell, i d’aquesta manera veure si el sistema serotonèrgic està implicat en el mecanisme d’acció de la MDMA.
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Kingsley, Michael Ian Charles. "Effects of phosphatidylserine supplementation on exercising humans." Thesis, Swansea University, 2006. https://cronfa.swan.ac.uk/Record/cronfa42268.
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The aim of this research was to investigate the effects of oral soy-derived phosphatidylserine (S-PtdSer) supplementation on the physiological responses to exercise, exercise performance/capacity and recovery following exercise. The results from this research provide evidence that short-term supplementation with 750 mg.d-1 S-PtdSer: 1. does not influence concentrations of cortisol or adrenocorticosteroid hormone in the circulation in young active male subjects. These data suggest that the current supplementation regime does not affect exercise-induced changes in the hypothalamo-pituitary-adrenal (HPA) axis. 2. is ineffective in attenuating the deleterious effects of exercise on perceived soreness, muscle damage, inflammation and oxidative stress in young active male subjects following eccentric exercise with a relatively low metabolic demand. 3. improved exercise capacity following intermittent cycling and tended to improve performance during prolonged intermittent running. These findings suggest that S-PtdSer might possess potential ergogenic properties. However, the mechanism(s) responsible for these findings remain to be determined.
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Spreekmeester, Emma S. "The effects of specific opiate receptor antagonists on the habituation of novelty-induced analgesia." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ29791.pdf.
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Watson, Anthony. "The psychopharmacological effects of blackcurrant phytochemicals in humans." Thesis, Northumbria University, 2014. http://nrl.northumbria.ac.uk/34139/.
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Self-medication of plant based foods and food extracts which have ostensible therapeutic benefits has considerably increased within non-clinical populations over the last two decades. The overarching reason for this rise in consumption is to improve health and cognitive performance. One such group of foods are flavonoid-rich berry fruits. In the literature, there has been a recent rise in evidence showing that the consumption of flavonoid-rich berries can modulate aspects of behaviour, especially memory, in animal models and in aged humans. Physiological parameters such as blood-flow and glucose levels; and biological mechanisms such as monoamine oxidase (MAO) activity and nitric oxide (NO) synthesis, which have the potential to impact human behaviour, are also shown to be manipulated by flavonoid compounds. The dark purple fruits of the blackcurrant (Ribes nigrum) are naturally high in flavonoids, however no literature assessing cognitive effects of their consumption is available. The main focus of this thesis was to assess the impact of standardised flavonoid-rich blackcurrant extracts upon cognitive performance and mood in healthy human participants. Two extracts were examined within the thesis, a freeze dried powder extract fortified to contain 30% anthocyanins (DelcyanTM) and a fresh from frozen cold pressed juice extract (Blackadder cultivar, Plant and Food Research Ltd). Utilising a series of randomised, between subjects, double bind studies, measures of memory, attention, executive function and psychomotor performance were implemented during the course of the thesis at various post-dose time points. Throughout the investigational chapters of the thesis, physiological parameters and potential mechanisms driving any behavioural changes were measured. Such measures included measures of central and peripheral haemodynamics, MAO inhibition, monoaminergic tone, prolactin secretion and post-prandial glucose profiles. Single doses of each of the blackcurrant extracts used in this thesis yielded positive results with effects of post-harvest extraction technique evident. Although no clear pattern of behavioural modulation was found after consumption of the blackcurrant extracts, there was some evidence to show increases in attention processes during cognitively demanding paradigms in young participants. No positive effects were evident upon any other cognitive paradigm. Physiological effects of acute blackcurrant supplementation included a modulation of post-prandial glucose profile and hemispheric dependent modulations of cerebral blood flow. Most strikingly, a pharmaceutical level inhibition of both monoamine oxidase isoforms and reductions in blood plasma prolactin were found. The findings of this thesis may have implications for enhancement of cognitive performance, attenuation in natural cognitive decline over the lifespan, and potentially, clinical applications in the treatment of neurological diseases.
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Upreti, Rita. "Metabolic effects of 5α-reductase inhibition in humans." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/11745.
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5α-reductases (5αRs) catalyse reduction of 4-pregnene steroids, most notably the androgen testosterone to its more potent metabolite dihydrotestosterone (DHT). Well-characterised isozymes of 5αR are designated 5αR1 and 5αR2. Inhibitors of 5αR, finasteride (a 5αR2 inhibitor) and dutasteride (a dual 5αR1 and 5αR2 inhibitor), are utilised in conditions where a reduction in androgen action is desired, including benign prostatic hyperplasia. Although 5αR2 is predominantly expressed in reproductive tissues, both isozymes, but particularly 5αR1, are expressed in metabolic tissues including liver and adipose and both metabolise glucocorticoids as well as androgens; therefore inhibition of 5αR may have consequences for metabolic health. This thesis addresses the hypotheses that 5αR1 inhibition with dutasteride decreases insulin sensitivity and causes dysregulation of the HPA axis in humans. Metabolism and the HPA axis were studied in men prior to and following 3 months of dutasteride (0.5 mg daily; n=16), finasteride (5 mg daily; n=16) or control (tamsulosin MR; 0.4 mg daily; n=14). Glucose disposal during hyperinsulinaemia was the primary endpoint, measured during a hyperinsulinaemic euglycaemic clamp, with d2-glucose and d5-glycerol tracers. Peripheral insulin sensitivity for both glucose uptake and NEFA suppression decreased with dutasteride versus both finasteride and control, while hepatic insulin sensitivity was preserved. Body fat increased with dutasteride, though was not accompanied by changes in metabolic or inflammatory gene transcript abundance in subcutaneous adipose biopsies, nor any differences in abdominal adipose depots on post-treatment MRI. Subtle dysregulation of the HPA axis was evident with both 5αR inhibitors, though to a greater degree with dutasteride and changes were largely compensated for. In support of this study, this thesis also describes the development, validation and application of two novel liquid chromatography tandem mass spectrometry assays; establishing compliance by measuring serum drug levels, and demonstrating effects of 5αR inhibitors on androgen metabolism and adrenal steroidogenesis by measurement of testosterone, DHT and androstenedione. In conclusion, 5αR1 inhibition with dutasteride, but not finasteride, induces peripheral insulin resistance and increases body fat. Findings presented may have important implications for patients prescribed dutasteride for benign prostatic hyperplasia.
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Bykov, Vladimir J. "UV-induced DNA damage in humans /." Stockholm, 1999. http://diss.kib.ki.se/1999/91-628-3345-6/.
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Jones, Gareth Elfed. "The physiological effects of massage post exercise in humans." Thesis, University of Liverpool, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.506443.
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Maidment, Graeme. "Effects of regional cooling on thermal balance in humans." Thesis, St George's, University of London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338862.
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Attwood, Angela Suzanne. "Conditioned cognitive and mood effects of caffeine in humans." Thesis, University of Birmingham, 2007. http://etheses.bham.ac.uk//id/eprint/6203/.
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Findings from animal studies suggest that stimuli present during the administration of psycho stimulant drugs can acquire the ability to elicit drug-like conditioned increases in locomotor activity. Human pharmacological drug-like conditioned responses are less well researched. There is evidence suggesting that stimuli paired with psycho stimulant administration can elicit drug-like physiological and subjective changes, as well as increases in drug craving. However, to date, no study has explicitly examined whether drug-induced facilitation of cognitive performance can be conditioned to drug-associated stimuli. The studies in the present thesis set out to test this and examine the extent to which the pattern of results conformed to the principles of Pavlovian classical conditioning. Caffeine was used as a model psycho stimulant drug, due to its well-reported ability to facilitate various aspects of cognitive performance. However, due to difficulties obtaining reliable effects of caffeine, the factors that may influence the effects of caffeine in a caffeine consumer sample were also investigated and reviewed. These factors included dose, expectancy, absorption interval, type of task, withdrawal and level of habitual consumption. It was concluded that caffeine can enhance cognitive performance, however these effects are inconsistent and may be influenced by individual differences. In addition, findings from a screening procedure indicated that responses to caffeine differ even within an overnight-deprived caffeine consumer population, an effect that appears to be dependent on the level of habitual caffeine intake. Due to such individual variation in the responses to caffeine, the conditioned effects were examined using a differential (i.e. within-subjects) conditioning procedure in which one set of environmental stimuli were paired with caffeine, and another set were paired with placebo. When subsequently tested free of drug, there were no differences in performance or mood responses at the conditioning test. However, there was evidence of caffeine facilitation on performance and mood during early conditioning trials that was lost on later conditioning trials due to a systematic improvement in the placebo condition. It was argued that this may be due to a conditioned response being acquired in the caffeine paired context which generalised to the placebo paired context. To test this hypothesis a second differential conditioning paradigm was conducted with fewer trials to establish whether evidence of a conditioned response could be observed in the caffeine-paired context during a placebo challenge. Evidence of a conditioned facilitation of reaction time was found, suggesting that the environment in which caffeine is ingested can acquire drug-like facilitations of cognitive performance.
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Bowin, Beth Marie. "Effects of Canines on Humans' Physiological and Perceived Stress." ScholarWorks, 2019. https://scholarworks.waldenu.edu/dissertations/7368.
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The bond between pet and owner has been shown to decrease stress-related physical, mental, and emotional disorders by lowering blood pressure and heart rate. The purpose of this study was to examine whether a nonpet canine would have the same effect in reducing physical symptoms of stress as a known dog. Human-animal bond theory, Human pressor test. Data were analyzed using repeated measures, analyses of variance, and t tests. Results indicated that interaction with a strange dog lowered heart rate and blood pressure significantly faster in the experimental group than in the control group. The positive social change implications of this research include policy and procedural accommodations for the use of canines as comfort animals for individuals in stressful conditions.
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Chen, Chung-Yen. "The Effects of Isoflavone Supplementation on Rats and Humans." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/28676.
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Isoflavones have antioxidant activities in vivo, however, their antioxidative potential against oxidative stress initiated by exercise was not explored. The first study investigated the effect of high-genistin isoflavone (HGI) supplementation on erythrocyte antioxidant enzymes and tissues' thiobarbituric reactive substances (TBARS) in acutely exercised one-year old rats. All tissue genistein concentrations increased after exercise. Ingestion of HGI seemingly enhanced running time to exhaustion, and maintained glutathione peroxidase (GPx) and catalase (CAT) activities decreased due to exercise. The second study investigated the dose effect of HGI supplementation. Genistein concentrations were significantly higher (P<0.05) in tissues of rats fed the 1045 PPM HGI diet than in rats fed 522 or 209 PPM HGI diets and increased the glutathione (GSH)/total glutathione (TGSH) ratio (P<0.03). Reductions of the in vivo MDA concentrations (P<0.05) were observed only in the plasma of rats fed 522 and 1045 PPM HGI diets compared to those fed 0 PPM (-1.08, -0.82, and 0.03 mM, respectively). Therefore, isoflavones at 522-1045 PPM HGI diet have antioxidative effects in rats.
The last two studies investigated the effect of isoflavone supplementation on the modulation of erythrocyte antioxidant enzyme activities, glutathione homeostasis, and other oxidative biomolecules in healthy young men undergoing 80%VO2pk exercise. In Study 3 exercise at 80%VO2pk increased oxidative stress which was best demonstrated by increased superoxide dismutase (SOD) activity (16.5%), GSH/TGSH ratio, in vivo MDA (12.6%), plasma uric acid (4.9%) and ferric reducing/antioxidant ability (FRAP) ( 7.8%). Therefore, 30 minutes 80% VO2pk exercise induced oxidative stress in moderately active college men. In study 4, four-week HGI supplementation produced plasma genistein and daidzein concentrations of 499 and 415 ng/ml, which were significantly increased to 633 and 539 ng/ml by exercise (P=0.04 and P=0.05). Isoflavones significantly decreased in vivo pre-exercise plasma MDA (P<0.05), increased pre-exercise blood TGSH (P=0.01) and pre-exercise erythrocyte SOD activity (P=0.0006), and maintained the decreased activities of GPx due to exercise at pre-exercise levels. Results demonstrated that isoflavones had antioxidant activity in vivo under normal physiological conditions in healthy young men. They also maintaining GPx activity which was decreased due to exercise, however, isoflavones may not overcome all oxidative stress initiated by intense exercise.Ph. D.
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Scott, Jessica. "The effects of acute exercise on cardiovascular function in humans." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/11172.
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In spite of numerous studies examining cardiac fatigue following acute exercise, there is a significant need for descriptive research that documents the nature and magnitude of this phenomenon in various populations. Accordingly, the aim of this series of studies was to comprehensively investigate the cardiovascular consequences of acute exercise in endurance trained (ET) individuals, normally active (NA) individuals, and heart transplant recipients (HTR). In the first investigation, 25 ET athletes were examined before a 160 km ultra-marathon and were re-assessed immediately following the race using traditional echocardiography, speckle tracking imaging, and cardiac biomarkers. Significant pre to post-race changes in systolic function (ejection fraction (EF): 66.8 ± 3.8 vs. 61.2 ± 4.0 %, p < 0.05), and diastolic function (E:A ratio: 1.62 ± 0.37 vs. 1.35 ± 0.33, p < 0.05) were observed. The second investigation used cardiac magnetic resonance imaging with tagging to study the impact of interval exercise on biventricular function in nine ET (VO₂max: 69 ± 7 mL/kg/min) and nine NA (VO₂max: 44 ± 9 mL/kg/min) males. There were no significant changes in RV and LV EF, torsion, rotation rate, strain, or strain rate post-exercise in the NA group. In the ET group, RV and LV EF, untwisting rate, apical rotation rate and circumferential strain were significantly decreased post-exercise. These results suggest that biventricular systolic and diastolic dysfunction occur following 14 min of high intensity exercise in ET athletes, a phenomenon which is not observed in NA individuals. The final investigation examined the cardiovascular responses during incremental and sustained (1 hr) sub-maximal aerobic exercise in 9 clinically stable HTR (age: 63 ± 10 yr; VO₂peak: 24.2 ± 10.9 mL/kg/min) and 11 healthy age-matched controls (6 recipient age-matched, RM; age: 60 ± 11 yr; VO₂peak: 36.3 ± 10.7 mL/kg/min, and 5 donor age-matched, DM; age: 35 ± 8 yr; VO₂peak: 51.1 ± 10.4 mL/kg/min) using traditional echocardiography. Despite maintained systolic function during incremental exercise, HTR had significantly reduced peak cardiac output, secondary to blunted heart rate and preload during exercise conditions. These findings provide the basis for future work examining the underlying mechanisms contributing to exercise-induced cardiac fatigue.
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Cook, Stephanie Lynne. "Effects of palmitic acid on endogenous cholesterol synthesis in humans." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq21160.pdf.
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Gunnare, Sara. "Fluorinated hydrocarbons used as refrigerants : toxicokinetics and effects in humans /." Stockholm, 2007. http://diss.kib.ki.se/2007/978-91-7357-231-6/.
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Nihlén, Annsofi. "Ethers as gasoline additives : toxicokinetics and acute effects in humans /." Solna : National Institute for Working Life (Arbetslivsinstitutet), 1998. http://diss.kib.ki.se/1999/91-7045-504-X/.
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Platt, Tyson Ladig. "The effects of static magnetic fields on directionality in humans." Auburn, Ala., 2007. http://repo.lib.auburn.edu/2007%20Spring%20Dissertations/PLATT_TYSON_9.pdf.
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Wood, Steven Matley. "Effects of β-carotene and selenium supplementation in aged humans." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186598.
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Aging is progressive deterioration of biological functions causing increased susceptibility to disease. This increased risk of disease is associated with a concomitant decrease in immune "responsiveness." Antioxidants are a group of compounds that prevent oxidative damage and disease. Researchers have focused on anti-oxidizing factors in disease prevention; however, nutrients which prevent oxidative damage may also have immunomodulating properties. βeta-carotene (BC), an antioxidant, has been shown to prevent cancer; while selenium, a key component of glutathione peroxidase, has shown promise in disease and cancer prevention. The objective was to determine if supplemental BC and selenium could enhance the immune response in elderly individuals. We investigated the functional responsiveness of lymphocytes that had been incubated with various concentrations of β-carotene and/or selenium. β-carotene enhanced natural killer (NK) cytotoxicity while selenium caused an immuno-suppressive effect. Interleukin-6 (IL-6) (a major factor in the acute phase immune response and B-cell differentiation) and IL-8 (a chemotactic factor) production was evaluated after short-term incubation with β-carotene or selenium. Selenium (0. 16 μg/ml) enhanced IL-6 production by 46 percent (P < 0.05) while the other concentrations of selenium or β-carotene did not significantly enhance IL-6 or IL-8 production. To further investigate selenium's and β-carotene's immunological effects, healthy elderly people (at least 60 years of age), were supplemented with high levels of BC and selenium. Participants were randomly assigned to receive a daily placebo, 45 mg β-carotene, 400 μg selenium, or 45 mg β-carotene plus 400 μg selenium for six months. NK cell activity and lymphocyte subpopulations were compared to pretreatment levels. Selenium and β-carotene supplementation for three months caused a statistically significant increase of 59% and 32% for NK cell activity respectively. At six months, NK cell activity returned to pretreatment levels. Selenium supplementation caused an increase in total T cells and CD4⁺ T cells. Selenium plus β-carotene supplementation increased the population of NK cells whereas β-carotene had little effect on phenotypic expression of lymphocytes. In conclusion, supplemental selenium and β-carotene enhanced immune function in healthy aged participants and their immunolomodulatory effects may partially explain their disease preventive properties.
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Nightingale, Julia Anne. "Inflamatory effects of inhaled pollutants : non-invasive assessment in humans." Thesis, University of London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391471.
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Venkatasubramanian, Sowmya. "Cardiovascular effects of the sirtuin and urocortin systems in humans." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/22919.
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Background: Cardiovascular disease continues to remain a leading cause of morbidity and mortality in both developing and developed worlds. The sirtuin and urocortin systems are novel hormone systems in humans with an emerging role in cardiovascular physiology and pathophysiology. Through a series of studies, this thesis examines the cardiovascular effects of SRT2104 (a novel small molecule SIRT1 activator) in otherwise healthy cigarette smokers and in patients with type 2 diabetes mellitus, and of urocortins 2 and 3 in healthy volunteers and in patients with heart failure. Methods: Twenty-four otherwise healthy cigarette smokers and 15 subjects with stable type 2 diabetes participated in a randomised, double blind, placebo controlled, crossover trial and received 28 days of oral SRT2104 (2.0 g/day) or matched placebo. Plasma SRT2104 concentrations, serum lipid profile, plasma fibrinolytic factors, markers of platelet and monocyte activation and pulse wave analysis and velocity were measured at baseline and the end of each treatment period together with an assessment of forearm blood flow during intra-arterial bradykinin, acetylcholine and sodium nitroprusside infusions. The pharmacodynamic profile of urocortins 2 and 3 were assessed in 18 healthy male volunteers recruited into a series of randomised, double blind, placebo controlled, crossover studies. Bilateral forearm venous occlusion plethysmography was performed during incremental intra-arterial infusions of urocortin 2 (3.6-120 pmol/min), urocortin 3 (1.2-36 nmol/min) and substance P (2-8 pmol/min) in the presence or absence of inhibitors of cyclooxygenase (aspirin), cytochrome P450 metabolites of arachidonic acid (fluconazole) and nitric oxide synthase (L-NG-monomethyl-arginine (L-NMMA)). Finally, 12 patients with stable heart failure (New York Heart Association (NYHA) II-IV) and 10 age- and sex-matched healthy volunteers were recruited to attend once each. Bilateral forearm arterial blood flow was measured using forearm venous occlusion plethysmography during incremental intra-arterial infusions of urocortin 2 (3.6-36 pmol/min), urocortin 3 (360-3600 pmol/min) and substance P (2-8 pmol/min). Results: SRT2104 was safe and well tolerated in otherwise healthy cigarette smokers and subjects with type 2 diabetes mellitus. There were no significant differences in fibrinolytic or blood flow parameters between placebo and SRT2014. Treatment with SRT2104 was associated with a significant reduction in augmentation pressure (P=0.0273) and a trend towards improvement in the augmentation index (AIx) and corrected augmentation index (0.10 > P > 0.05 for both) without significant changes in pulse wave velocity (PWV) and time to wave reflection (Tr) (P > 0.05). Administration of SRT2104 had a favourable effect on lipid profile in otherwise healthy cigarette smokers in comparison to placebo. Urocortins 2 and 3 evoked arterial vasodilatation (P < 0.0001) without tachyphylaxis but with a slow onset and offset of action. Inhibition of nitric oxide synthase with L-NMMA reduced vasodilatation to substance P and urocortin 2 (P≤0.001 for both) but had little effect on urocortin 3 (P > 0.05). Neither aspirin nor fluconazole affected vasodilatation induced by any of the infusions (P > 0.05 for all). In the presence of all three inhibitors, urocortin 2- and urocortin 3-induced vasodilatation were attenuated (P < 0.001 for all) to a greater extent than with L-NMMA alone (P≤0.005). The vasodilatory effects of urocortins 2 and 3 were preserved in patients with heart failure. Conclusion: Activation of SIRT1 through SRT2104 improved lipid profile but did not produce demonstrable differences in vascular or platelet function with some effect on measures of arterial stiffness. Urocortins 2 and 3 appear to be potent arterial vasodilators whose vasomotor responses remained preserved in patients with heart failure and were at least partly mediated via the endothelium. Both hormone systems hold potential in their role in cardiovascular disease in man but require further studies to help translate findings of this thesis to clinical practice.
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Sundlöf, Sebastian. "Light and Paint:perceptual and emotional effects on space and humans." Thesis, KTH, Ljusdesign, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-280082.
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In 21st century Scandinavia, the use of colored paint in the built environment has decreasedconsiderably. Instead, color changing LEDs can be found in many homes. In this thesis, an experimentwas set up to investigate how these two coloring methods differ and coincide with regards toemotional response and perception of materiality. Four cubicles, two painted and two colored bylight, were evaluated by ten participants. The painted cubicles were perceived as more material intheir appearance with regards to texture and color than their counterparts. A greater feeling ofnervousness, stress, and disorientation was felt in the light-colored cubicles as opposed to aheightened feeling of inspiration, excitement and calmness in the painted cubicles. Though it isimportant to remember the difference was not significant. In addition, preconceived connotations tothe color tone could be an influencing factor and so further studies on additional tones should beconducted. Lastly, benefits and drawbacks with the coloring methods were discussed.
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Reilly, Mark P. (Mark Peter). "The Effects of Interresponse Intervals on Behavioral Variability in Humans." Thesis, University of North Texas, 1993. https://digital.library.unt.edu/ark:/67531/metadc501037/.
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The present experiment studied the relationship between interresponse intervals and behavioral variability. Subjects emitted sequences of 4 keypresses on two keys on a variability schedule that delivered points when the current 4-response sequence differed from the previous 5 sequences. Three experimental conditions were studied; no interresponse interval, 4-s interresponse interval and 8-s interresponse interval. Interresponse intervals followed each of the first three responses in each sequence. Two groups were used to study initial training histories. Group 1 was first exposed to the no-interresponse interval condition. Group 2 was first exposed to the 4-s interresponse interval condition. Subjects were then exposed to the different interresponse interval conditions. There was little change in variability across conditions. However, the variability observed in the subjects first exposed to the 4-s interresponse interval was greater than the variability observed in subjects first exposed to no-interresponse interval. There was higher-order response patterning in both groups, but it was more pronounced in the no-interresponse interval group.
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Hanifin, John P. "Circadian, neuroendocrine and neurobehavioral effects of polychromatic light in humans." Thesis, University of Surrey, 2015. http://epubs.surrey.ac.uk/807999/.
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In the last eighteen years there has been the identification of a novel photopigment, melanopsin, and its subsequent localization to human intrinsically photosensitive retinal ganglion cells (ipRGCs). Since melanopsin’s peak sensitivity is in the short wavelength portion of the visible spectrum (from 447 nm to 484 nm), there has been a steady increase in studies investigating the physiological effects of blue light. This thesis examines polychromatic light mixtures of blue light for circadian, neuroendocrine and neurobehavioral effects in humans. White blue-enriched fluorescent lamps were tested at equal photon densities for increased efficacy for melatonin suppression, increased alertness, and circadian phase shifting. Results demonstrated that compared to white fluorescent light, blue-enriched fluorescent light was significantly stronger for suppressing melatonin and resulted in significantly reduced subjective sleepiness. Blue-enriched light, however, was not significantly stronger in eliciting circadian phase-delay or increasing objective measures of alertness. Next, blue-appearing narrowband solid-state light was examined for its ability to acutely suppress nocturnal melatonin as well as enhance cognitive performance and alertness in healthy men and women when compared to dim white lighting. The results demonstrated that narrowband blue solid-state light was significantly stronger for melatonin suppression compared to dim white light. Subjective and objective assessments of alertness, however, were not significantly increased by blue-enriched light exposure. The final study tested the hypothesis that certain combinations of light wavelengths are additive or opponent to the photoreceptor system that mediates the melatonin suppression. The results demonstrated that the melatonin suppression responses to dual narrow bandwidth light combinations were not significantly different from single wavelength exposures. Taken together, the results suggest that melanopsin sensitivity is not the sole consideration for predicting the efficacy of white polychromatic lighting. The different effects of blue light on alertness, circadian phase-shifting and melatonin suppression imply a either a context dependent sensitivity and/or differential involvement of the classical photoreceptors in these light responses.
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Friswell, J. "The effects of morphine and oxycodone on memory in humans." Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1444683/.
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The side effects of opiates are an important area of study as detriments to activities of daily living and to quality of life might outweigh detriments caused by untreated pain. Furthermore there has been relatively little research into the cognitive effects of opiates. This thesis aims to explore the effects of morphine and oxycodone on memory. Part one of the thesis comprises a literature review of the cognitive effects of opiates. It presents an overview of the current levels of understanding as well as highlighting the clinical importance of furthering our understanding. It also briefly raises the question of how gender may interact with the drug effects. Part 2 comprises the empirical paper. It reports a randomised, placebo-controlled, double-blind study comparing the effects of 10 mg morphine, 5 mg oxycodone and placebo on 18 healthy volunteers. The findings were that these doses did not produce significant impairments in most cognitive measures, and there was no retrograde memory impairment as was seen in a previous similar study involving cancer patients. It found some subtle drug effects on working memory, episodic memory and subjective experiences. More importantly, it revealed some subtle interactions of gender and weight with drug implying that the current practice of prescribing doses of oral opiates that are not determined by weight and gender may be inappropriate. Part 3 comprises a critical appraisal of the research. It includes a description of my personal experience during the research process as well as exploring further issues of validity within the study.
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Le, Merrer Julie. "Opium, opiacés, opioi͏̈des : du remède millénaire à la physiologie des morphines endogènes." Bordeaux 2, 2000. http://www.theses.fr/2000BOR2P106.
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Schwartz, Alexander. "Examining the Effects of Weight Loss on Energy Expenditure in Humans." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20455.
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Being able to effectively match energy intake to energy expenditure (EE) is an important aspect in preventing weight re-gain in the post-obese. Although it is generally agreed upon that resting EE decreases concomitantly with weight loss, there is no set standard comparing the deviations with differing weight loss protocols and additionally, controversy remains as to whether this decrease is greater than can predicted. In order to address these issues 2977 subjects were analyzed using a systematic review and the differences of both the protocol and length of various interventions in addition to sex were compared. Next, data was selected from this systematic review and 815 subjects were analyzed for weight loss-induced changes in resting EE, FM and FFM. Another subgroup of studies (n = 1450) was analyzed and compared against the Harris-Benedict prediction equation to determine whether the changes in resting EE were greater than what was expected. Finally, in order to determine which factors may be involved in regulating changes in resting EE during weight loss, a secondary analysis was performed on 28 post-menopausal women (age= 50.4 ± 2.0 yrs; BMI= 32.4 ± 5.2 kg/m²) who were submitted to a 6-month caloric restriction. Body composition (DXA), resting EE (indirect calorimetry), physical activity EE (PAEE) and total EE (TEE) (doubly-labelled water) were measured before and after the 6 month weight loss. Blood samples were collected before and after to measure leptin and peptide YY. The results indicate that there was indeed a depression in resting EE during weight loss regardless of the type of intervention utilized. Furthermore, these findings suggest that the changes could not fully be explained by changes of FM and FFM alone and that leptin may be an important contributor to the changes of resting EE during weight loss.
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Coté, Anita Theresa. "The effects of strenuous exercise on cardiovascular function in healthy humans." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44040.
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Araghi-Niknam, Moshen 1960. "Effects of dehydroepiandrosterone supplementation in aged humans and C57BL/6 mice." Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/282417.
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DHEA (dehydroepiandrosterone) is a major adrenal hormone, with known accepted function. In both animals and humans low DHEA and DHEA-sulfate levels are associated with a number of problems in the aging: immunosenescence, increased mortality, increased incidence of several cancers, loss of sleep, decreased feelings of well-being, osteoporosis, atherosclerosis and premature death. DHEA hormone replacement in aged mice significantly normalized immunosenescence suggesting that this hormone plays a key role in aging and stimulating immune regulation in mice. Similarly osteoclasts and lymphoid cells, were stimulated by DHEA replacement which should delay osteoporosis. Recent studies do not support the original suggestion that low serum DHEA levels were associated with Alzheimer's and other losses of mental function in aged people. As DHEA modulates energy metabolism low levels should affect lipogenesis and gluconeogenesis, increasing the risk of diabetes and heart disease. Most of the actions of DHEA restoration are hypothesized from epidemiological or animal model studies and need to be tested in human trials. Those conducted in humans show essentially no toxicity of DHEA treatment at levels restoring serum DHEAS levels without evidence of altering some aging physiological systems. Thus DHEA is a steroid whose deficiency could facilitate development of some diseases common to the aged. Dehydroepiandrosterone (DHEA) and DHEA-sulfate (DHEAS) are steroids, synthesized from cholesterol (Fig. 1.1). While DHEA is secreted primarily by the adrenal gland in larger quantities than any other adrenal steroid including cortisol, the precise functions of DHEA and DHEAS in humans are not known (1-5). The decline of DHEAS levels during aging is parallel to development of immunosensecence, an inability to conserve protein, a physical frailty, decreased muscle mass, an increased fat mass, decreased ability to cope, disrupted sleep patterns and increased incidence of disease. Thus DHEAS serves as a marker of aging in humans. While the precise biological functions of DHEA and DHEAS are not known, both animal and human studies suggest some hypotheses while dispelling others. Therefore key physiological dysfunctions are investigated here to determine biological relationships which participate in the declining blood levels of DHEA with age.
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Gil, Lostes J. "A study of chemosensory effects of volatile organic compounds on humans." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/19202/.
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Indoor air quality is closely associated with human health since most people spend approximately ninety per cent of their time indoors. Environmental tobacco smoke, which is a very complex mixture, is one of the most important contributors to indoor air pollution, especially significant is its contribution to indoor concentrations of volatile organic compounds (VOCs). Evaluation of chemosensory irritation (eye irritation and nasal irritation) caused by VOCs uses human subjects as panelists, and is very time consuming and costly. Thus prediction of chemosensory irritation, e.g. by quantitative structure-activity relationships (QSARs) involving the use of VOC physicochemical parameters (descriptors), is highly desirable. The prediction of sensory responses on humans by QSARs requires the use of experimentally determined descriptors in the QSARs, at least for the most successful methods to date. In this work descriptors for more than 100 VOCs have been determined, using experimental gas chromatographic data, gas-liquid and liquid-liquid partition coefficients. A number of gas chromatographic columns were characterized in this work; these columns cover a large range of polarities. VOC descriptors were then introduced into QSARs to fit and then to predict eye irritation thresholds (EITs) and nasal irritation thresholds (NPTs). Furthermore, this project established a general connection between EITs and other chemosensory responses in humans. If there were a connection between those values, this would enable inter-conversion to be made, and would provide a method of estimating one threshold from the other. An attempt was made to demonstrate the suitability of using experimental Draize eye test scores and NPT values to calculate EIT values. A new equation to predict EIT values was proposed that includes a very much larger set of experimental values from other biological endpoints than just EIT, and hence should be statistically more sound than an equation based on a limited number of EIT values only. Psychometric functions are used in chemosensory studies to describe the probability of chemosensory detection as a function of concentration. These functions are experimentally determined, again using human subjects, so function prediction is desirable. Psychometric functions have been predicted for several VOCs for odour, eye and nasal irritation, and nasal lateralization. A physicochemical model for delivery of VOCs to eye receptor neurons has been developed based on the two-stage model. In this model the complexity of the VOC delivery to the cornea throughout the different layers of the pre-corneal tear film leading to a succession of equilibrium processes is reduced to a much more simple overall equilibrium process. Finally, it is known that there is a critical molecular dimension along a given homologous series, e.g. n-alkylbenzenes and 2-ketones, beyond which eye irritation is not evoked (at the cut-off point). This work has been continued by investigating several homologous series of compounds that are found in tobacco smoke, and it seems possible to predict the ‘cut-off’ point by using energy minimization of the system and molecular dynamics in aqueous phase. Software packages such as Molecular Operating Environment 2007.09 (Chemical Computing Group) and Hyperchem version 7.5 (Hypercube Inc.) were used to perform molecular dynamics and energy minimization.
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Cot??, Anita Theresa. "The effects of strenuous exercise on cardiovascular function in healthy humans." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44040.
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RATIONALE: Strenuous exercise has been shown to elicit transient reductions in ventricular systolic and diastolic function, as well as impaired autonomic function. The effects of training status and sex on the development of these acute alterations are not known. The aim of these studies was to examine vascular adjustments, cardiac mechanics and autonomic function as the result of strenuous exercise in healthy, endurance-trained (ET) and normally active (NA), males and females. Statistical significance was set at p < 0.05. The first investigation explored sex differences in the cardiovascular response to an ultra-marathon in 25 runners. Ventricular function was reduced similarly in men and women. Novel associations of life-time ultra-marathons and degree of longitudinal strain were found, demonstrating the absence of cumulative stress on the heart with long-term prolonged strenuous exercise. The second investigation assessed ventricular function following high-intensity interval exercise (HIT) in 39 men and women. Changes in cardiac mechanics were not differentiated by training status, however, lower baseline arterial stiffness was associated with twist augmentation. Men demonstrated greater reductions in contractility and higher arterial elastance post-exercise than women. The third investigation assessed autonomic function following HIT and orthostatic stress in 33 men and women. Throughout the intervention, women displayed greater strain, strain rate, and baroreflex sensitivity, but there were no interactions of condition by sex. Autonomic function decreased to a greater degree in ET, but also improved most rapidly in recovery. Thus, it would appear that the cardiac and autonomic stability of ET and women during an orthostatic challenge is not compromised in the face of HIT. The fourth investigation analyzed post-exercise hypotension (PEH) following HIT in 21 individuals. Hypotension occurred similarly in all individuals however, men experienced greater reductions in stroke volume. These findings suggest men engage a different mechanism of PEH compared to women. The fifth investigation explored cognitive function in recovery from HIT. Cognition was improved post-exercise and persisted for four hours post-exercise. SUMMARY: Together, these studies provide novel findings pertaining to the effects of sex and training status on the cardiovascular responses to strenuous exercise.
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Boonsong, Tantip. "Effects of diets and exercise upon metabolic gene expression in humans." Thesis, University of Nottingham, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.478953.
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Gola, Joëlle Muriel Rachel. "The prediction of chemosensory effects of volatile organic compounds in humans." Thesis, University College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252180.
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Wang, Jian Ping. "Health effects of chronic arsenic toxicity in humans and laboratory animals /." St. Lucia, Qld, 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16894.pdf.
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Azarnoush, Kian. "The Effects of Amixicile on Sub-gingival Biofilm Cultured from Humans." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5349.
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Periodontitis is an inflammatory disease of the oral cavity induced by anaerobic bacteria, that remains to be the primary cause of tooth loss in adults worldwide. Finding an anti-microbial therapeutic to selectively target periodontal pathogens has proven to be difficult, and current treatment modalities only provide a transient benefit. Amixicile is a non-toxic, readily bioavailable novel antimicrobial that targets strict anaerobes through inhibition of the activity of Pyruvate Ferredoxin Oxidoreductase (PFOR), a major enzyme mediating oxidative decarboxylation of pyruvate, a critical step in metabolism. Our study aimed to evaluate the efficacy of amixicile in inhibiting the growth of bacteria harvested from the complex sub-gingival biofilm of patients with chronic periodontitis. We hypothesize that amixicile will selectively inhibit pathogenic anaerobic bacteria collected from patients, with the same efficacy as metronidazole, the current accepted treatment modality.
Plaque samples were harvested from patients with severe chronic periodontitis and cultured under anaerobic conditions. The microbiomes were grown in the presence of amixicile and metronidazole and the growth was compared to that of bacteria grown in the absence of the antimicrobials. Following 24 hour incubation, bacterial DNA was isolated and bacterial quantity was evaluated by quantitative PCR (qPCR) using primers specific for 12 bacterial species: P. gingivalis (Pg), P. intermedia (Pi), F.nucleatum (Fn), S.gordonii (Sg), S. anginosus (Sa), V. atypical (Va), L. acidophilus (La), A.actinomycetemcomitans (Aa), T.denticola (Td), S.mutans (Sm), S.sanguis (Ss), and 16s. Individual qPCR runs were combined to represent an overall average of CT value differences.
Amixicile treatment groups exhibited statistical significant reductions (PP. intermedia, F. nucleatum and Veillonella atypical. When comparing amixicile to metronidazole, amixicile performed with similar efficacy with the largest effect seen for PFOR bacteria. Our conclusion supports amixicile as a potent inhibitor of anaerobic bacteria, and could be a potential new therapeutic antimicrobial in the treatment of periodontal disease
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HUI, WINNIE K. "HISTORY OF THE EVOLUTION OF HUMANS AND THEIR EFFECTS ON WILDLIFE." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1108950402.
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Becker, James N. M. 1979. "Effects of Two Marker Placement and Data Analysis Methods on Running Gait Analysis." Thesis, University of Oregon, 2010. http://hdl.handle.net/1794/10470.
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xiii, 143 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.This study evaluated the effects of two marker placement methods and two data analysis methods on running gait analysis. Markers placed on the shoe heel counter were compared with markers placed directly on the calcaneous and visible through heel windows cut into the shoe. When analyzed using a traditional group design no significant differences were found between marker conditions for rear foot eversion excursion, percent stance at which peak eversion occurred, maximal instantaneous eversion velocity, or maximal instantaneous vertical loading rate. Ankle frontal plane variability was significantly different between conditions. When analyzed with a single subject design some individuals demonstrated significant differences between conditions while others did not. In some individuals the heel windows condition revealed previously masked coupling parameters thought to be related to injury. The results of this study suggest the heel windows method and single subject analysis should be used for a longitudinal study of runners.
Committee in Charge: Dr. Li-Shan Chou, Chair; Dr. Louis Ostemig; Dr. Stanley James
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IWASE, Satoshi, Qi FU, Kenichi NARITA, Eiichi MORIMOTO, Hiroki TAKADA, and Tadaaki MANO. "Effects of Graded Load of Artificial Gravity on Cardiovascular Functions in Humans." Research Institute of Environmental Medicine, Nagoya University, 2002. http://hdl.handle.net/2237/2775.
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Woodcock, Elizabeth Ann Psychology Faculty of Science UNSW. "Effects of environmental enrichment on fundamental cognitive processes in rats and humans." Awarded by:University of New South Wales. Psychology, 2004. http://handle.unsw.edu.au/1959.4/20488.
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This thesis examined whether it is possible to enhance core elements of the information processing system with specific forms of environmental stimulation. The first series of experiments demonstrated that a preweaning environmental enrichment procedure that provided 60 minutes of daily multisensory stimulation accelerated the development of long-term contextual memory and enhanced inhibitory processing in young rats. That is, whilst stimulated and non-stimulated rats exhibited long-term memory of a context at 26 days of age, only stimulated rats showed this ability at 18 days of age. In addition, stimulated rats showed a faster rate of extinction of long-term contextual memory at 21 days of age, which was taken as evidence of enhanced inhibitory learning (i.e., context ??? no US) in these rats. Subsequent experiments with adult rats demonstrated that a combination of preweaning multisensory stimulation and postweaning rearing in an enriched environment improved the (1) specificity of long-term contextual memory, (2) speed of contextual information processing, and (3) availability of attentional resources. More specifically, enriched-reared rats demonstrated superior ability to discriminate between two similar contexts in comparison to standard-reared rats. In addition, enriched-reared rats showed superior memory of a context when there was limited time available to form a memory of that context. This finding was taken to indicate that rats that receive environmental enrichment are able to process contextual information more rapidly. Finally, standard-, but not enriched-, reared rats showed less conditioning to a discrete stimulus when it was presented in combination with a stronger stimulus during training compared to when it was presented by itself. The finding that enriched-reared rats did not show this overshadowing effect suggests that these rats have greater availability of attentional resources to divide between two stimuli that are competing for attention. The experiments with rats were followed by two experiments with children that investigated the effects of a computerised cognitive training procedure on information-processing speed. These experiments demonstrated that 30-minutes per weekday of training in rapid decision-making for three to five weeks improved children???s performance on two tests of processing speed (i.e., a choice reaction time and odd-man-out task). In addition, the speeded training improved children???s ability to sustain their attention and inhibit impulsive responses on a continuous performance test (Test of Variables of Attention). The cognitive training procedure had no effect on children???s performance on a measure of fluid intelligence (Raven???s Standard Progressive Matrices). The results of the experiments reported in this thesis suggest that a number of fundamental cognitive processes can be modified by environmental conditions that place increasing demands on the information-processing system. A neurobiological model, focusing on myelin, axon diameter, and the glutamatergic, glucocorticoid, noradrenergic, and cholinergic systems, was proposed in order to explain the observed effects of environmental stimulation on cognition in children and rats. The rationale for attempting to enhance fundamental cognitive processes was that improving these processes should ultimately improve general intellectual functioning. With respect to this aim, the correlational data from the present experiments with children revealed promising trends towards greater improvements on the tests of fundamental cognitive processes in those children in the training group with slower processing speed at the start of the intervention. This finding suggests that cognitive training may be even more effective at enhancing processing speed and other fundamental cognitive processes in children with intellectual impairments???who reportedly have slower processing speed than normal children. However, the extent to which training-related improvements in fundamental cognitive processes generalise to improvements in general cognitive functioning is unclear. That is, there is insufficient evidence that processing speed and other fundamental cognitive processes are causally related to intelligence. It is therefore essential that future cognitive training research is mindful of related developments within the intelligence and information processing literature.
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Lawrence, Christopher J. "Dexmedetomidine as anesthetic adjuvant cardiovascular and anesthetic effects in animals and humans /." Maastricht : Maastricht : Universiteit Limburg ; University Library, Maastricht University [Host], 1998. http://arno.unimaas.nl/show.cgi?fid=6057.
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Russo, Antonietta. "Effects of hyperglycaemia on small intestinal and anorectal motor function in humans /." Title page, table of contents and summary only, 1997. http://web4.library.adelaide.edu.au/theses/09MSM/09msmr969.pdf.
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O'Neill, Frans Hendrik. "Effects of dietary plant sterols and stanols on cholesterol metablolism in humans." Thesis, Imperial College London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396345.
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Claydon, Leica Sarah. "Electrostimulation (TENS) in healthy humans: effects of different frequencies, intensities and stimulation." Thesis, Keele University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486018.
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Aim: To investigate the efficacy of transcutaneous electrical nerve stimulation (TENS) parameter combinations (defined in terms ofintensity, frequency and stimulation site) on experimental pain models in healthy humans. Methods: A systematic review ofthe literature was conducted. This served to inform th~ design ofthe primary studies, which investigated the simultaneous applications of TENS at two sites using different parameter combinations. Randomized, doubleblind, parallel-group, placebo-controlled trials were employed using repeated measurements ofpressure pain threshold. The sample size was defined so as to provide 80% statistical power, at a two-tailed 5% significance level, to detect a large effect (~ 0.08), comparing each parameter combination to both aplacebo group and a control group. Results: Systematic review evidence did not support the use ofcommonly applied TENS applications, such as 'Conventional TENS' and 'Acupuncture-like TENS'. Results ofthe primary studies results revealed, that the concurrent application (TENS at two sites) of such modes (Segmental 'Conventional TENS' and extrasegmental 'Acupuncture-likeTENS') does not achieve maximal hypoalgesia. In concurrent TENS applications, high-intensity TENS is required for maximal andprolonged bypoalgesic responses, along with different frequencies at ea.ch site. Furthermore, continuous stimulation is recommended, the alternating frequency pattern (3 seconds 4H.z13 seco,nds 110Hz) did not achieve optimal effects. Conclusions: Ineffective responses to TENS may be explained in part by inadequate TENS parameter applications. The results ofthese investigations further contribute to the evidence base concerning the hypoalgesic efficacy of this modality.
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Martens, Kristina Marie. "Benign Environmental Distractors Modulate the Anxiolytic Effects of Marijuana Administration in Humans." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/281.
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One experiment examined the relationship between smoked marijuana and anxiety generated by the anticipation of a stressor paired with a salient, benign distractor. It was hypothesized that smoking one marijuana cigarette with an estimated &delta9-THC content of 26.25 mg, relative to placebo, would reduce anxiety generated by an anticipatory stressor paired with a benign distractor. In the experiment 14 marijuana users with a mean frequency of marijuana use per week of 2.07 (Range = 1-3) were administered one marijuana cigarette (active vs. placebo) per experimental session. A significant Drug × Session interaction was observed such that during the first experimental session, participants administered active marijuana reported non-significant decreases in negative affect, relative to placebo, while those administered active marijuana during the second experimental session reported significant increases in negative affect. This finding indicates that large individual differences in response to drug type (active vs. placebo) occurred within the participant sample. The results are discussed in terms of the influence of individual differences and contextual factors on the observed differential affective responses to &delta9-THC in order to identify which participants experienced the greatest benefit in negative affect reduction from &delta9-THC.
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Neal, Emily R. "ESCHERICHIA COLI STRAIN DIVERSITY IN HUMANS: EFFECTS OF SAMPLING EFFORT AND METHODOLOGY." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/984.
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Studies investigating Escherichia coli strain diversity and demographics in human hosts are frequently inconsistent regarding sampling effort and methodology while current strain typing methods are often expensive or laborious. To rectify these inconsistencies, sampling effort was investigated by comparing the diversity of 15-isolate collections to 100-isolate collections from 3 human subjects. Temporal variation in E. coli strain diversity was also studied by collecting 15 isolates once every 6 months. Additionally, strain identification and diversity collected by different sampling methods (fecal swabs vs. anal swabs collected at different times around defecation) were compared to identify any inherent biases in sampling method. This study employed pyroprinting, a new inexpensive and simple strain typing method using pyrosequencing, to generate DNA fingerprints (or pyroprints) based on the Intergenic Transcribed Spacer sequences in the ribosomal RNA operon to differentiate E. coli strains. Differences in strain diversity were apparent when comparing sampling efforts. The sampling effort investigation suggested that certain subjects hosted very large and highly diverse E. coli strain populations such that even 100 isolates may not fully represent E. coli strain populations in human hosts. Instead, the sampling effort required to accurately represent strain demographics may depend on strain richness and evenness within each host. The temporal investigation yielded similar or greater strain abundance and diversity compared to other typing methods in the literature suggesting pyroprinting is a similarly discriminating tool. When agglomerated over time or by subject, no significant differences in diversity were observed between subjects or between sampling methods despite visible differences in strain richness and evenness.
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Kiselev, Andrey. "Incorporating Affective Behaviours into Virtual Agents and Evaluating Their Effects on Humans." 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/151932.
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Briem, Kristin. "Gait and function in knee osteoarthritis effects of hyaluronan injection /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 183 p, 2008. http://proquest.umi.com/pqdweb?did=1601513361&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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