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Amino acids in eight South African topsoil samples
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. D.P. Botha --- , Republic of South Africa M.F. Philpott --- , Republic of South Africa M.J. van der Merwe --- , Republic of South AfricaAmino acids were determined by gas chromatography after acid hydrolysis in eight South African topsoil samples. Total amino acid nitrogen in these samples varied from 11% to 47% of total soil-N. A difference in relative proportions of the amino acids... -
A procedure for determining the minimum bulk density of soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A. D.J. Da C. Nhantumbo --- Department of Soil Science, Republic of South Africa A. T.P. Bennie --- Department of Soil Science, Republic of South AfricaThe purpose of this study was to establish a procedure and develop equipment for determining the minimum bulk density of soils. Six soils with silt-plus-clay contents varying between 8 and 41% were selected. The determination consisted of pouring the soil... -
A review of orange roughy Hoplostethus atlanticus fisheries, estimation methods, biology and stock structure
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: T. A. BranchOrange roughy Hoplostethus atlanticus are unusual fish. They form dense aggregations that have fuelled lucrative fisheries at great depths (600–1 400 m), especially off Namibia, New Zealand and Australia. They are thought to be very long-lived (>100 years, maturity at... -
THE DETERMINATION OF CHLOROPHYLL
a IN WATER CONTAINING SEDIMENTItem type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.C. Grobler --- Department of Water Affairs, South Africa Elizabeth Davies --- Department of Water Affairs, South AfricaThe presence of sediment at concentrations of 0,2% by mass in water samples significantly lowered the amount of chlorophyll a that could be measured. Two types of sediment differed in their ability to lower the chlorophyll a concentration. The chemically... -
A SPECIFIC ULTRAVIOLET ABSORBANCE BAND OF MICROCYSTIS AERUGINOSA TOXINS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.N. Eloff --- Department of Botany, South AfricaIt could be shown that toxic fractions of Microcystis aeruginosa extracts always had a 240 nm absorbance band, There was a linear relationship between toxicity and UV absorbance at 240 nm of extracts from different isolates of Nicrocystis. One ml... -
AN ASSESSMENT OF A RAPID AND CONVENIENT SPECTROPHOTOMETRY ADAPTATION OF THE WINKLER PROCEDURE FOR THE DETERMINATION OF DISSOLVED OXYGEN IN FRESH WATERS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: P.J. Ashton --- National Institute for Water Research, South Africa A.J. Twinch --- National Institute for Water Research, South AfricaThe use of a spectrophotometric adaptation of the standard Winkler procedure to measure the dissolved oxygen content of water samples is described and assessed. The technique allows the rapid processing of routine samples and the accuracy, precision and sensitivity of... -
Fostering Self-Determination and Resilience Through Sports Counselling: Psychosocial Development of Youth in Botswana
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Taunya Marie Tinsley --- California University of Pennsylvania, Lisa Lopez Levers --- Duquesne University,Sports can promote pro-social behaviors and confidence in physical abilities among participants. We conducted an extensive review of the literature on the ways in which youth in Southern African countries, severely affected by the HIV/AIDS pandemic and other hardships may... -
The effect of positive end-expiratory pressure on pulse pressure variation
Item type: Journal Article • Journal: Southern African Journal of Anaesthesia and Analgesia • Authors: FJ Smith --- Department of Anaesthesiology, School of Medicine, Faculty of Health Sciences, M Geyser --- Department of Anaesthesiology, School of Medicine, Faculty of Health Sciences, I Schreuder --- Department of Anaesthesiology, School of Medicine, Faculty of Health Sciences, PJ Becker --- Biostatics Unit,Objectives: To determine the effect of different levels of positive end-expiratory pressure (PEEP) on pulse pressure variation (PPV). -
Parenting styles and psychological needs influences on adolescent life goals and aspirations in a South African setting
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Nicolette V. Roman --- Child and Family Studies, Department of Social Work, South Africa Eugene L. Davids --- Child and Family Studies, Department of Social Work, South Africa Alice Moyo --- Child and Family Studies, Department of Social Work, South Africa Lauren Schilder --- Child and Family Studies, Department of Social Work, South Africa Marlies Lacante --- Department of Psychology, Belgium Willy Lens --- Department of Psychology, BelgiumThe present study examined the role of parenting styles and basic psychological needs in the adoption of goals and aspirations of learners, as well as for their psychological wellbeing (positive versus negative affect) in a South African sample of learners... -
Exercise in futility or dawn of Afrikaner self-determination: an exploratory ethno-historical investigation of Orania
Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: FC de Beer --- Department of Anthropology and Archaeology, South AfricaDue to their ethnic diversity nation states have the arduous task of accommodating various identity conscious groups within their boundaries. Nation-building programmes and strategies are employed mostly to unite the heterogeneous populations of nation states, as is currently also being... -
New age-determination method based on fast growth rate of Cape hake Merluccius capensis in Namibia
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MR Wilhelm --- Department of Fisheries and Aquatic Science, Namibia SC Paulus --- National Marine Information and Research Centre (NatMIRC), Namibia S Kashava --- National Marine Information and Research Centre (NatMIRC), NamibiaNamibia’s most important commercial fisheries resource, the shallow-water Cape hake Merluccius capensis, is currently assessed using statistical catch-at-age analysis. Age data obtained from otoliths constitute an important data component of this model. Recent age-validation studies of M. capensis showed that... -
Making a difference and earning a living: Healthcare professionals’ perspectives on working with persons with special healthcare needs
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Victoria Cutts --- , South Africa Henry D. Mason --- , South Africa Vikki Botes --- , South AfricaThis qualitative study explored six (female = 5) healthcare professionals’ motivation to work with persons with special healthcare needs. Thematic analysis revealed three themes; namely making a difference in people’s lives, personal life stories, and extrinsic motivation. The findings suggest... -
Size at maturity, maturity stages and sex ratio of tigerfish Hydrocynus vittatus Castelnau, 1861 in Lake Kariba, Zimbabwe: assessing the influence of decades of fisheries exploitation
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Terence Magqina --- , Zimbabwe Tatenda Dalu --- , South Africa Lindah Mhlanga --- , Zimbabwe Tamuka Nhiwatiwa --- , ZimbabweSize at maturity, sex ratio and maturity stages are key population parameters in fisheries management of exploited stocks because they influence survival of fish populations. The decline in Hydrocynus vittatus catches during the tigerfish competition and along the shoreline of... -
Adolescent hookah pipe use: Comparing users’ and non-users’ harm perception, needs, and motivation
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Zainab Kader --- , South Africa Rik Crutzen --- , The Netherlands Nicolette V. Roman --- , South AfricaThis study compared the harm perception, motivation, and basic psychological needs of adolescent hookah pipe users and non-users. We surveyed 1 201 adolescents aged 13–19 years old from South Africa who were hookah users (n = 256) and non-users (n... -
Instigating transformative entrepreneurship in subsistence communities: Supporting leaders' transcendence and self-determination
Item type: Journal Article • Journal: Africa Journal of Management • Authors: Steven W. Rayburn --- Texas State University, USA Gideon Ochieng --- , KenyaThis research exposes a process of bottom-up development that supports leaders’ transcendent motives and self-determination needs to instigate transformative entrepreneurship within their communities. The process is illuminated by actions taken in development organizations working within subsistence communities. Findings reveal that... -
Disordered eating behaviours and basic psychological need satisfaction: the mediating role of anxiety symptoms in preadolescents
Item type: Journal Article • Journal: Journal of Child & Adolescent Mental Health • Authors: Tess E Marshall --- School of Psychology, Cardiff University, UK Kai S Thomas --- School of Psychology, Cardiff University, UK Netta Weinstein --- School of Psychology, Cardiff University, UK Ross E Vanderwert --- School of Psychology, Cardiff University, UKObjective: According to self-determination theory, satisfied basic psychological needs can be a protective factor for psychopathology, including eating disorders and anxiety symptomatology. However, most research has focused on adolescent and adult populations, with less work examining perceived basic psychological need... -
The role of autonomy and competence in retaining Dutch hotel staff post-COVID-19
Item type: Journal Article • Journal: Research in Hospitality Management • Authors: Sofiia Norenko --- Wittenborg University of Applied Sciences, The Netherlands Emmah Muchoki --- Wittenborg University of Applied Sciences, The Netherlands Vanessa de Oliveira Menezes --- Wittenborg University of Applied Sciences, The Netherlands René Rijnders --- Wittenborg University of Applied Sciences, The NetherlandsThis article explores potential changes in employee motivation for retention in the Dutch hotel industry after the COVID-19 pandemic, applying the self-determination theory to examine autonomy and competence. An online survey was designed and applied to 298 Dutch hotel staff... -
Overqualification perception and employee voice: Mediation by dual path autonomous and controlled motivation
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Enhai Yu --- School of Economics and Management, North China Electric Power University, China Xiao Ge --- School of Economics and Management, North China Electric Power University, China He Ding --- School of Economics and Management, North China Electric Power University, ChinaDrawing on person–vocation fit and self-determination theory, we explored the role of the autonomous and controlled motivation in the relationship between overqualification perception and employee voice. The sample consisted of 251 employees from different enterprises in China (female = 52.6%;... -
Psychological empowerment and job burnout in Chinese kindergarten teachers: The mediating effect of occupational stress
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Ruiqian Li --- College of Teacher Education, Shaoxing University, China Jie Hou --- College of Teacher Education, Shaoxing University, China Xiongying Liu --- College of Teacher Education, Shaoxing University, China Tong Shen --- College of Teacher Education, Shaoxing University, China Jiaying Xu --- College of Teacher Education, Shaoxing University, China Ziyu Wu --- College of Teacher Education, Shaoxing University, ChinaWe explored the role of occupational stress in the relationship between psychological empowerment and job burnout in kindergarten teachers. Chinese female kindergarten teachers (n = 243) were participants (mean age = 28.2 years, SD = 5.08 years; specialist and below... -
An analysis of guest attitude toward dining at green restaurants in Qatar
Item type: Journal Article • Journal: Research in Hospitality Management • Authors: MC Ashim Sagar --- Human Resource Management, FTC Qatar, Qatar Eddy Kurobuza Tukamushaba --- College of Business, University of Doha for Science and Technology, Qatar Juliet Gladies Jayasuria --- College of Business, University of Doha for Science and Technology, Qatar Khalid Ibrahim Al-Sulaiti --- Marketing, Al-Rayyan International University College in partnership with University of Derby UK Doha–Qatar, QatarThis study examines how interpersonal influence, green menu attributes and eco-friendly attributes shape guest attitudes toward green dining in five-star hotels in Qatar, and how these attitudes influence their willingness to dine at green restaurants. Using a quantitative approach, a...