Volunteering and Social Activism: Pathways for Participation in Human Development

This discussion paper explores the following questions, drawing on the above-mentioned background study: How is volunteering an d social activism understood?; How do volunteering and social activism foster people's participation?; What is the relationship between participation and development?; What is required to widen and sustain participation

Service Enquiry Service in the 21st Century

The workshop set out to acknowledge and explore the potential of youth service as a strategy for social, economic and democratic development, to identify new work that needs to be undertaken, and to increase knowledge about youth

Five-country Study on Service and Volunteering in Southern Africa: South Africa Country Report

The aim of the study was to document and analyse civic service and volunteering in South Africa

Five-country Study on Service and Volunteering in Southern Africa

In the context of globalization, civic service and volunteering is emerging as a growing social phenomenon and a field of inquiry internationally. This research was done to strengthen knowledge and understanding of service and to build research capacity in order to develop service as a field of inquiry and to strengthen its knowledge base and practice

Volunteering and Civic Service in Three African Regions: Contributions to Regional Integration, Youth Development and Peace

This paper broadly looks at the role of youth volunteering in cultivating peace and development in Sub-Saharan Africa

Five-Country Study on Service and Volunteering in Southern Africa

Five-Country Study on Service and Volunteering in Southern Afric

The influence of Rooibos (Aspalathus linearis) on adrenal steroidogenic P450 enzymes

Thesis (MSc (Biochemistry))--University of Stellenbosch, 2009.This study: 1. Describes the preparation of unfermented and fermented rooibos methanol and aqueous extracts. 2. Investigates the influence of unfermented and fermented rooibos methanol and aqueous extracts on the binding of natural steroid substrates to ovine adrenal microsomal cytochrome P450 enzymes, demonstrating that the binding of natural steroids is inhibited in the presence of rooibos extracts. 3. Describes an assay demonstrating the inhibitory effect of rooibos extracts on the catalytic activity of cytochrome 17α-hydroxylase (CYP17) and cytochrome 21-hydroxylase (CYP21) in ovine adrenal microsomes. 4. Investigates the influence of unfermented and fermented rooibos methanol extracts on the catalytic activity of individual cytochrome P450 enzymes – CYP17 and baboon CYP21, that are expressed in COS1 cells. 5. Demonstrates that fractions of the unfermented rooibos methanol extract inhibits the binding of natural steroid substrate to microsomal cytochrome P450 enzymes as well as the catalytic activity of baboon CYP21 expressed in COS1 cells. 6. Investigates the inhibitory influence of individual rooibos flavonoids on the catalytic activity of baboon CYP21 expressed in COS1 cells

Non-destructive measurement of internal quality of apple fruit by a contactless NIR spectrometer with genetic algorithm model optimization

Spectrometric methods based on near infrared radiation (NIR) are commonly used effectively in the agricultural and food industry. However, these methods still face limitations whereby meeting requirements for application such as nondestructive quality testing of large fruits and automated sorting and grading is still a challenge. A Fourier transform (FT)-NIR spectrometer (emission head, EH mode of Matrix-F) that simulates on-line sample scanning (contactless, large sample size (100 mm)) was used to predict internal properties of apple fruit. The EH was compared to laboratory multipurpose analyzer (MPA) FT-NIR spectrometer using two contact-sample presentation modes with relatively smaller sample size (≤22 mm); namely, the integrating sphere (IS) and the solid probe (SP). Three apple cultivars (Golden Delicious, Granny Smith and Royal Gala) sourced from two retail stores (in Stellenbosch, South Africa) were used to constitute variability in the sample set. Partial least squares regression (PLSR) prediction models for internal quality (total soluble solids (TSS) and titratable acidity (TA)) were developed and validated on external test samples in various scenarios. Genetic algorithm (GA) based optimization of PLS models was used to produce optimal models prior to instrumental comparison.Model optimization using GA improved performance by a margin of 30% of the original root mean square error of cross validation for the contactless system bringing it closer to the performance of models from the MPA. The EH's performance makes it an attractive option for achieving on-line application of NIR spectroscopy for sorting apples based on internal quality. Keywords: FT-NIR, Calibration transfer, Model performance, Genetic algorithm, Apple qualit