Browsing Faculty of Natural and Agricultural Sciences by Author "10176527 - Steyn, Hendrik Stefanus"
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A norm for an academic literacy placement test
Van der Walt, Johann L.; Steyn, Faans (SAALT/SAVTO, 2016)A test series usually consists of various versions of a test. Test-takers and consumers of tests expect all these versions to be at the same level of difficulty, but this is very difficult to achieve at the test design ... -
Association of waist circumference with perception of own health in urban African males and females: the Sympathetic Activity and Ambulatory Blood Pressure in Africans (SABPA) study
Botha, J.; Malan, L.; Potgieter, J.C.; Steyn, H.S.; De Ridder, J.H. (Health & Medical Publishing Group (JEMDSA), 2012)Background: Current waist circumference (WC) cut-points of the Joint Statement Consensus (JSC) (male ≥ 94 cm, female ≥ 80 cm) were compared with a recently proposed WC cut-point (RPWC) (male ≥ 90 cm, female ≥ 98 cm). In ... -
Cardiometabolic markers to identify cardiovascular disease risk in HIV-infected black South Africans
Van Rooyen, J.M.; Fourie, C.M.T.; Steyn, H.S.; Koekemoer, G.; Huisman, H.W.; Schutte, R.; Malan, L.; Glyn, M.; Smith, W.; Mels, C. (SA Medical Association, 2014)BACKGROUND: The prevalence of HIV is the highest in sub-Saharan Africa; South Africa (SA) is one of the most affected countries with the highest number of adults living with HIV infection in the world. Besides the traditional ... -
Change over three years in adolescents' physical activity levels and patterns after a physical activity intervention: play study
Pienaar, A.E.; Kruger, H. Salome; Steyn, H.S.; Naudé, D. (Edizioni Minerva Medica, 2012)AIM: This study aimed to determine over a three-year period what the PA levels and patterns of adolescents will be after participating in a physical activity (PA) intervention. METHODS: African adolescents (158 boys, 211 ... -
Chronic defensiveness and neuroendocrine dysfunction reflect a novel cardiac troponin T cut point: the SABPA study
Malan, Leoné; Hamer, Mark; Von Känel, Roland; Steyn, Hendrik S.; Malan, Nicolaas T. (Elsevier, 2017)Background Sympatho-adrenal responses are activated as an innate defense coping (DefS) mechanism during emotional stress. Whether these sympatho-adrenal responses drive cardiac troponin T (cTnT) increases are unknown. ... -
Cohort profile: sympathetic activity and ambulatory blood pressure in Africans (SABPA) prospective cohort study
Malan, Leoné; Hamer, Mark; Steyn, Hendrik S.; Malan, Nicolaas T.; Frasure-Smith, Nancy (Oxford Univ Press, 2015)Adapting to an over–demanding stressful urban environment may exhaust the psychophysiological resources to cope with these demands, and lead to sympathetic nervous system dysfunction. The evidence that an urban–dwelling ... -
Consumers’ knowledge about and attitudes towards lucerne (Medicago sativa l.)
Mielmann, Annchen; Steyn, Faans; Bothma, Carina; Hugo, Celia J. (SAAFECS, 2017)Over the past few years, interest has grown about the health benefits of lucerne (alfalfa), however, little is known about consumers’ attitudes towards consuming this forage legume. Therefore, the aim of this study was to ... -
Coping facilitated troponin T increases and hypo-responsivity in the copeptin-HPA-axis during acute mental stress in a black cohort: the SABPA study
Myburgh, Catharina Elizabeth; Malan, Leoné; Möller, Marisa; Steyn, Faans; Malan, Nicolaas Theodor (Elsevier, 2019)Background Defensive coping (DefS) was associated with a vulnerable cardiovascular profile in blacks. The copeptin/vasopressin system is a manifestation of hypothalamic-pituitary-adrenal-axis activity and may act as an ... -
Cultural coping as a risk for depression and hypertension: the SABPA prospective study
Le Roux, S.; Lotter, G.A.; Steyn, H.S.; Malan, L. (Clinics Cardive, 2018)Objectives: In past studies, a lack of social support has been associated with cardiovascular disease (CVD) risk, particularly in black Africans. However, whether or not coping strategies have beneficial effects on blood ... -
Defensive active coping facilitates chronic hyperglycaemia and endothelial dysfunction in African men: the SABPA study
Malan, L.; Hamer, M.; Steyn, H.S.; Schutte, R.; Smith, W.; Van Rooyen, J.M.; Fourie, C.M.T.; Malan, N.T. (Elsevier, 2013)Background: Dissociation between behavioural defensive active coping (AC) control albeit physiological “loss of control” responses was associated with silent ischaemia and structural wall abnormalities in African men. Whether ... -
Determining the waist circumference cut off which best predicts the metabolic syndrome components in urban Africans: the SABPA study
Prinsloo, J.; Malan, L.; De Ridder, J.H.; Potgieter, J.C.; Steyn, H.S. (Thieme Publishing, 2011)Various studies have shown that the relationship between waist circumference (WC) and abdominal obesity is age, gender as well as ethnicity-dependent. WC criteria for Sub Saharan Africans have not been defined by the ... -
Determining the waist circumference cut off which best predicts the metabolic syndrome components in urban Africans: the SABPA study
Malan, Leoné; Potgieter, Johannes Cornelis; Steyn, Hendrik Stefanus; Prinsloo, J.; De Ridder, Johannes Hendrik (Thieme Publications, 2011)Various studies have shown that the relationship between waist circumference (WC) and abdominal obesity is age, gender as well as ethnicity-dependent. WC criteria for Sub Saharan Africans have not been defined by the ... -
Development and evaluation of a rapid multiplex-PCR based system for Mycobacterium tuberculosis diagnosis using sputum samples
Mutingwende, Isaac; Vermeulen, Urban; Steyn, Faans; Grobler, Anne; Viljoen, Hendrik (Elsevier, 2015)Global tuberculosis (TB) control and eradication is hampered by the unavailability of simple, rapid and affordable diagnostic tests deployable at low infrastructure microscopy centers. We have developed and evaluated the ... -
Dual radiolabeling as a technique to track nanocarriers: the case of gold nanoparticles
Rambanapasi, Clinton; Barnard, Nicola; Grobler, Anne; Buntting, Hilton; Jordaan, Anine; Steyn, Hendrik; Zeevaart, Jan Rijn (MDPI, 2015)Gold nanoparticles (AuNPs) have shown great potential for use in nanomedicine and nanotechnologies due to their ease of synthesis and functionalization. However, their apparent biocompatibility and biodistribution is still ... -
An educator approach towards learner discipline as a prerequisite in dealing with learner misconduct
Eloff, Cecile Henriëtte; Oosthuizen, Izak Johannes; Steyn, Hendrik Stefanus (The Association for Christian Higher Education / Die Vereniging vir Christelike Hoër Onderwys, 2010) -
The effect of the Pheroid delivery system on the in vitro metabolism and in vivo pharmacokinetics of artemisone
Grobler, Lizette; Grobler, Anne; Haynes, Richard; Steyn, Hendrik Stefanus; Masimirembwa, Collen; Thelingwani, Roslyn (Taylor & Francis, 2014)Objectives: The objectives were to determine the pharmacokinetics (PK) of artemisone and artemisone formulated in the Pheroid® drug delivery system in primates and to establish whether the formulation affects the in vitro ... -
Estimating an effect size in one-way multivariate analysis of variance (MANOVA)
Ellis, Susanna M.; Steyn, H.S. (Psychology Press, 2009) -
Prior experience, cognitive perceptions and psychological skills of senior South African rugby players
Kruger, Pieter; Malan, Dawid Daniel Jacobus; Potgieter, Johannes Cornelis; Steyn, Hendrik Stefanus (Stellenbosh University, 2010) -
The protective role of oestradiol against silent myocardial ischemia and hypertension risk in South African men: the SABPA study
Malan, Nicolaas T.; Von Känel, Roland; Steyn, Hendrik S.; Kruger, Ruan; Malan, Leoné (Elsevier, 2017)Background Oestradiol has a protective effect on coronary artery health in women but the effect it has on men, is controversial. A translational approach was followed to assess whether sex hormone levels are associated ... -
Stress and neurovascular coupling: a red flag? The SABPA study
Malan, Leoné; Hamer, Mark; Von Känel, Roland; Smith, Wayne; Steyn, Faans; Malan, Nicolaas (Karger, 2019)Neuronal hyperactivity mediates communication between neurons and blood vessels (neurovascular coupling) and increases susceptibility for retinal ganglion cells functionality. Contrastingly, monoamine depletion and ...