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G Adamson

Publications and source records attributed to G Adamson.

9 recordsLinked to original sources
PubMed2000

An evaluation of the factor structure and predictive utility of a test anxiety scale with reference to students' past performance and personality indices.

BACKGROUND: Scales of test anxiety have developed in parallel with the evolution of the test anxiety construct. A recently refined version of the Revised Test Anxiety scale offers the prospect of independently assessing different test anxiety factors. AIMS: The study aims to ascertain if the four-factor structure of the RTA scale found in Egyptian and American samples can be replicated in an Irish sample, and to examine the comparative predictive utility of cognitive and emotionality factors in relation to examination performance. The study also examines whether results support an Interference or Deficits Model of test anxiety, and assesses the relationship of test anxiety to personality variables believed to be relevant to academic performance. SAMPLE: The participants were 117 male and female psychology students from the University of Ulster. Their average age was 23 years. METHOD: Data were analysed using correlation analysis, multiple regression, factor analysis and ANOVA. Examination performance was the criterion variable; predictor variables were the four factors of test anxiety, three personality measures and previous examination performance. RESULTS: Four-factor test anxiety invariance across diverse population is supported by the model in the analysis. Cognitive factors are significant negative predictors of performance. The data do not support either an Interference or Deficits Model of test anxiety, and personality factors, especially self-efficacy, were significantly (negatively) related to test anxiety. CONCLUSIONS: The two cognitive factors have emerged as the most substantial negative predictors of examination performance. Attention to these factors and to relevant personality indices are commended as a potentially fruitful strategy for remedial intervention.

Achievement↗
PubMed1998

Effect of modifying O2 diffusivity and delivery on glomerular and tubular function in hypoxic perfused kidney.

Is O2 diffusivity within renal capillaries rate limiting for O2 delivery to hypoxic renal tubules? Equations based on diffusion theory and developed here predict that soluble hemoglobin (Hb) increases O2 diffusivity by a factor of 1 + [442 Hb%/(P50 + PO2)], where P50 is the partial pressure of O2 at which the Hb is half saturated. To examine the effect of P50 and Hb concentrations on renal function, we perfused isolated rat kidneys with Hb-P35 (P50 = 35 mmHg) and Hb-P11 (P50 = 11 mmHg). Venous PO2 was lower with Hb-P11 (10 +/- 1 vs 16 +/- 1 mmHg with arterial PO2 = 35 mmHg and 28 +/- 2 vs. 40 +/- 2 mmHg with arterial PO2 = 140 mmHg; P < 0.001). Perfusate P50 did not influence vascular resistance, glomerular filtration rate, O2 consumption, Na reabsorption, protein excretion, or free water clearance. Percent glucose and phosphate excretion were lower with Hb-P11 than with Hb-P35 (P < 0.001). Urine glucose was 0.17 mmol/l with Hb-P11 and 0.77 mmol/l with Hb-P35 (P < 0.001). Hb-P35 (2%) doubled O2 delivery and lowered glucose and phosphate excretion to the level obtained with 1% Hb-P11. Thus Hb-P11 delivered O2 twice as effectively as Hb-P35 to high-affinity sodium glucose and phosphate cotransporters in the late proximal tubule (S3 segment). Hb-P11 may also have shunted O2 from the outer cortex to the outer medulla and facilitated O2 diffusion where PO2 was low. We conclude that diffusivity is a limiting factor in delivery of O2 to hypoxic tubules.

Animals↗
PubMedDate not supplied

The in vitro production of antibodies to mitochondrial antigens by peripheral blood mononuclear cells from patients with primary biliary cirrhosis.

Peripheral blood mononuclear cells from 7 patients with primary biliary cirrhosis and 7 healthy control subjects were studied for their ability to produce antibodies to mitochondrial antigens in vitro. Peripheral blood mononuclear cells were collected by lymphapheresis and cultured with or without pokeweed mitogen for 10 days. The culture supernatants were then tested for antibodies to mitochondrial antigens by both immunofluorescence microscopy and a microtiter ELISA. Peripheral blood mononuclear cells from 5 of 7 patients with primary biliary cirrhosis but from none of the healthy controls produced antibodies to mitochondrial antigens spontaneously (without pokeweed mitogen stimulation). In contrast, peripheral blood mononuclear cells from 6 of 7 patients with primary biliary cirrhosis and from 6 of 7 control subjects synthesized detectable levels of antibodies to mitochondrial antigens after stimulation with pokeweed mitogen. In general, peripheral blood mononuclear cells from the primary biliary cirrhosis patients produced higher titers of antibodies to mitochondrial antigens in culture than cells from healthy controls. Furthermore, the antibodies to mitochondrial antigens reactivity produced by peripheral blood mononuclear cells of primary biliary cirrhosis patients exhibited a specificity for the M2 mitochondrial antigen which is present on the inner membrane of mitochondrial cristae and which is closely associated with a mitochondrial ATPase activity. In contrast, the antibodies to mitochondrial antigens reactivity produced by peripheral blood mononuclear cells of healthy controls appeared to be directed at a broader range of mitochondrial antigens. These findings indicate that, inpatients with primary biliary cirrhosis, there is a marked expansion of B lymphocyte clones that produce an antibody to a specific mitochondrial antigen.

Adult↗