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The purpose of this paper is to determine the learners’ perceptions on the use of online resources at the Namibian College of Open Learning (NAMCOL) Yetu Yama Resource Center.

This study used a mixed methods research approach which was also used by other researchers such as Hamutumwa (2014). It enabled the researchers to delve into the topic under study by conducting a survey using self-administered questionnaires to collect data from learners, and a semi-structured interview guide, to collect data from the Librarian, the Director and tutors. The target population for the study was Grade 12 distance learners registered with NAMCOL for the academic year 2016, librarians and tutors. Convenient sampling was used to select 200 Grade 12 distance NAMCOL learners: one Director, one Librarian and five tutors were purposeful selected as they manage the Yetu Yama Resource Centre. The Statistical Package for the Social Sciences (SPSS) was used to generate descriptive data, while qualitative data were manually analysed using content analysis. This approach enabled the researcher to identify key themes which emerged from the interviews.

Almost all the learners (159) opted for printed materials. The challenges experienced by learners included slow internet, as indicated by 78 (39 per cent); limited facilities, 60 (30 per cent); and inability to find relevant information, 46 (23 per cent), coupled with lack of proper guidance on the use of e-resources as indicated by 16 (8 per cent) learners.

This study was limited to Yetu Yama Resource Center. The results cannot be generalised to all distance learners in Namibia.

The results of this study could guide librarians in Namibia when planning and/or upgrading e-resources.

Once the learners are equipped with the required skills, they will make optimum use of the e-resources which are provided by NAMCOL.

This is the first study to be conducted at NAMCOL, and it is hoped that the results will be applied to other tertiary institutions which offer distance education in Namibia.

This paper aims to investigate the electroporation phenomenon in a single cell exposed to ultra short (μs) and high voltage (kV) electric pulses.

The problem is addressed by two complementary approaches. First, numerical simulations based on an asymptotic approximation derived from the Smoluchowski theory are used to calculate the pore generation, growth and size evolution at the membrane of a spherical cell model, immersed in a suspension medium and consisting of cytoplasm and membrane. The numerical calculations are solved using the finite difference method. Second, an in vitro experiment with LLC-MK2 cells is carried out in which electroporation was monitored with molecules of propidium iodide. This part also comprehended the design and manufacturing of a portable electric pulse generator capable of providing rectangular pulses with amplitude of 1,000 V and duration in the range of 1-μs to 100-μs. The pulse generator is composed of three modules: a high voltage DC source, a control module, and an energy storage and high voltage switching.

The numerical simulations considered a 5-μm radius cell submitted to a 500 kV/m rectangular electric pulse for 1-μs. The results indicate the formation of around 3,500 pores at the cell membrane, most of them, around 950, located at the poles of the cell aligned to the applied electric pulse, with radii sizes varying from 0.5-nm to 13-nm. The in vitro experiment considered exposition of LLC-MK2 cells to pulses of 200 V, 500 V, and 700 V, and 1-μs. Images from fluorescence microscopy exhibit the LLC-MK2 cells with intense red, a strong evidence of the electroporation.

The work presents a thorough study of the electroporation phenomenon combining two complementary approaches, a rigorous numerical simulation and a detailed in vitro experiment.

Investigates the differences in protocols between arbitral tribunals and courts, with particular emphasis on US, Greek and English law. Gives examples of each country and its way of using the law in specific circumstances, and shows the variations therein. Sums up that arbitration is much the better way to gok as it avoids delays and expenses, plus the vexation/frustration of normal litigation. Concludes that the US and Greek constitutions and common law tradition in England appear to allow involved parties to choose their own judge, who can thus be an arbitrator. Discusses e‐commerce and speculates on this for the future.

Workflow systems are often associated with business process re‐engineering (BPR). This paper argues that the functional access control requirements in workflow systems are rooted in the scope of a BPR project. A framework for access control in workflow systems is developed. The framework suggests that existing role‐based access control mechanisms can be used as a foundation in workflow systems. The framework separates the administration‐time and the run‐time aspects. Key areas that must be investigated to meet the functional requirements imposed by workflow systems on access control services are identified.