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Background: The formulation, implementation and evaluation of inventory policies are vital for adequate management of inventory in organisations to ensure seamless flow of inventory and customer satisfaction. Inventory policies offer the required guidelines on how inventory should be managed in organisations to attain inventory management goals. However, it is unclear whether these guidelines are efficaciously implemented to enhance the inventory management performance of Eskom and Transnet in the Gauteng Province. Objective: This study sought to investigate the efficacy of inventory policy implementation at each of the selected SOEs in the Gauteng Province. Method: The study employed a qualitative research design with a sample of twenty-four inventory staff, of which fifteen were from SOE1 and nine from SOE2. The sampled population (inventory staff) were selected purposefully at each SOE in the Gauteng Province. Data were mainly gathered by means of semi-structured interviews and were thematically analysed. Results: The study generated four themes that reveal the extent of inventory policy implementation and its associated impact on inventory costs at each SOE. These themes included adherence to inventory policy, inventory policy violations, implementation extent of inventory policy, inventory growth rate and the associated increase in inventory carrying costs and lack of inventory planners’ planning skills. Conclusion: Inventory policies were not fully implemented at each SOE. Poor inventory purchasing decision and violation of inventory policies contributed to inventory growth rate and excess inventory carrying and its associated costs. This therefore negatively affects the inventory management performance of SOE 1 and SOE 2.

A high-technology complex system can be supported during its extended life by using an integrated logistics support system (ILSS). The process to develop an ILSS is used and is familiar in industrial and military complex systems. This paper discusses the advantages and implications of developing an ILSS for high-technology complex systems that are being used beyond their intended designed life. A literature review of the integrated logistics support (ILS), obsolescence, and diminishing manufacturer sources and material shortages (DMSMS) literature was conducted. The ILS and obsolescence components of several high-technology complex systems were studied for this paper.

Supporting and maintaining complex systems in developing countries has numerous challenges, especially in systems that suffer from obsolescence and operate beyond their designed life. Existing methodologies in developing an integrated logistics support system (ILSS) in developed countries are based on resources that are readily available, while in developing countries this is not always the case, and so grounded design rules within a robust framework are required. Various methods and six case studies of high technology systems were used for this paper. Obsolescence effects are considerably wider than the retirement and obsolescence component of present frameworks.

Nutrient losses have to be avoided in agricultural systems for agronomic and environmental reasons. However, they are known to be potentially large and variable. Results from twenty nine trials aiming at quantifying nitrogen (N), phosphorus (P), potassium (K) and carbon (C) flows and losses from barn and manure storage for beef cattle (Belgian Blue double-muscled breed) were synthesized. They included variation in barn type (tied stall and deep litter), leading to contrasted manure types (respectively semi-solid manure and deep litter manure) of small groups (n = 4) of heifers or bulls. Despite uncertainties pointed out by non-zero P or K balances, we established for manure storage, a relation between K losses by flowing out as liquid and rainfalls: K lost (%K stored) = 100*(1–0.99*e(−0.00078*rainfalls (mm)); n = 28). We also emphasized, within the particular set of data treated, the effects of barn type (approached by STRAWr; kg straw kg-1 DM in feed), manure storage duration (d), nitrogen in feed concentration (NFEED; g N kg-1 DM) and storage temperature (°C) on N losses from the whole system (N lost (% N input)=−33.33 + 0.0869*storage duration+1.11*storage temperature+27.9*STRAWr+1.278*NFEED; r² = 0.700; n = 29) such as the strong relation between C and N losses during manure store per day of storage (N lost (% N stored d-1) = 0.038 + 0.617*C lost (% C stored d-1)). We also observed that, even if N and C inputs in the system were higher in deep litter systems due to straw supply, the amounts of N and C remaining in the manure after being stored were very similar, indicating higher losses of these nutrients from deep litter systems compared to tied stalls. These findings will further help in modeling cattle housing systems for nutrient cycling optimization. However, the relations established have to be validated for other tied stall and deep litter systems regarding the diversity in manure management for each barn type. Furthermore, when comparing manure provided under different housing systems, other agronomical (e.g. their sanitization due to heat increase when stored, ease of application to soil after storage) or environmental (e.g. greenhouse gas emissions) aspects have to be considered.

Research on biochar has increased, but its long-term effect on the fertility of temperate agricultural soil remains unclear. In Wallonia, Belgium, pre-industrial charcoal production affected former forested areas that were cleared for cultivation in the nineteenth century. The sites of traditional charcoal kilns, largely enriched in charcoal residues, are similar to soil amended with hardwood biochar more than 150 years ago. We sampled 17 charcoal kiln sites to characterize their effect on soil properties compared with adjacent reference soils. Charcoal-C content was estimated by differential scanning calorimetry. The kiln soil contains from 1.8 to 33.1 g kg−1 of charcoal-C, which markedly increases organic C:N and C:P ratios. It also contains slightly more uncharred soil organic carbon (SOC) than the reference soil, which accords with larger total N content. We measured a small increase in nitrates in the kiln soil that might relate to greater mineralization and nitrification of organic N. Frequent application of lime raised the pH to values close to neutral, which offset the residual effect of charcoal production on soil acidity. A cation exchange capacity (CEC) of 414 cmolc kg−1 was estimated for charcoal-C, whereas that of uncharred SOC was 213 cmolc kg−1. Despite the large CEC of the kiln soil, exchangeable K+ content was no different from the adjacent soil, whereas exchangeable Ca2+ and Mg2+ contents were considerably larger. Charcoal enrichment has little effect on available, inorganic and total P, but it can form strong complexes with Cu, which reduces the availability of the metal. Biochar is very persistent in soil; therefore, long-term implications should not be overlooked. Highlights Charcoal kiln soil contains from 1.8 to 33.1 g kg−1 of charcoal-C, which raises C:N and C:P ratios. Charcoal-C content was estimated by differential scanning calorimetry. We estimated a CEC of 414 cmolc kg−1 for charcoal-C and 213 cmolc kg−1 for uncharred SOC. Retention of exchangeable K+ remained unaffected by charcoal but that of Ca2+ and Mg2+ increased.

Summary In Wallonia, Belgium, intensive in situ charcoal production that was linked closely to pre-industrial smelting and steel-making affected a large part of the forested area in the late eighteenth century. Charcoal kiln relics can be detected under forest as domes of about 10 m in diameter, with the topsoil greatly enriched with charcoal residues. We sampled 19 charcoal kiln sites and the adjacent reference soil by soil horizon on four different soil types (Arenosols, Luvisols, Cambisols and Podzols). Data were analysed with linear mixed models to assess the effect of the charcoal kiln site on soil properties in relation to depth and soil conditions. We also addressed the evolution of soil properties over time by a comparison of the soil characteristics at a currently active kiln site. The charcoal-rich topsoil has a larger C:N ratio and cation exchange capacity (CEC) per unit of organic carbon than the reference soil. The largest CECs per unit of carbon were observed on soil with coarser textures. On acidic soil, the increase in base saturation in the subsoil reflects the past liming effect of ash produced by wood charring, whereas the topsoil is re-acidified. The acidity of carbonate-rich Cambisols, however, is not reduced. Regardless of soil type, the kiln topsoil is greatly depleted in exchangeable K+ and available P, which may be attributed to the small affinity of the exchange complex of charcoal for K+ and a decrease in P availability with time. Therefore, we recommend further research on the long-term effects of biochar on the dynamics of plant nutrients.

In temperate regions, perennial forage-based cropping systems are expected to face an increasing frequency of summer droughts over the next decades prompting the need for more resilient cultivars. However, most efforts mainly focus on Mediterranean-type environments where the plant survival is often engaged. Under temperate environments, vapor pressure deficit (VPD) is a key component of drought, because its variation alters the crop transpiration rate (TR) and therefore its ability to fix carbon even in well-watered conditions. Despite this knowledge, there is no available data about the diversity of whole-plant TR responses to VPD and soil moisture among key forage crops such as alfalfa, red clover, cock’s foot and perennial ryegrass. Further, field-based evidence is lacking regarding the links between TR responses to VPD and yield under drought. Here, we combined experimental approaches characterizing gas exchange responses to VPD and soil moisture at scales that ranged from the growth chamber to the field, where yields were characterized both quantitatively and qualitatively over the course of 2 years on 8 genotypes from the 4 above species. A significant variability in TR responses to increasing VPD and soil water deficit was found among locally-adapted cultivars. More importantly, TR responses to VPD – but not to decreasing soil moisture – were found to be consistently correlated to relative yield performances under drought, in a way indicating that conservative water use under high evaporative demand promoted higher yield outputs. In contrast, yields under drought were unrelated to canopy temperature and leaf gas exchange measured in the field. Further, no link was found between TR responses to VPD and qualitative yield traits such as digestibility indicating that the hypothesized water saving strategy does not improve yield at the expense of forage quality. This study opens the way for future forage breeding and management strategies taking advantage of the diversity of TR responses to drought to implement climate-change resilient forage-based systems.

This study examines the intensity effect of a mentoring intervention for Head Start teachers, the Individualised Learning Intervention (ILI), as it impacts child social emotional outcomes. Pairs of Mentor and Protege teachers across three sites in two states were randomly assigned to intervention and control groups. Mentors in the intervention group participated in a 50-hour mentor seminar and supported the intervention Protege teachers’ professional growth and development across one Head Start school year. Mentors themselves were also supported by a Mentor Coordinator. As part of a quasi-experimental study of implementation fidelity effects, the intensity of mentoring intervention was measured by the Intensity of Intervention Scale and the intervention group was divided into high and moderate intensity levels. Evidence is presented for the effects of high intensity levels of the ILI Mentoring programme, relative to moderate intensity and control conditions, on the children in the Protege teachers’ classr...

The business environment is constantly changing. For organisations to gain competitive advantage, they require innovative methods to achieve future business goals. The capital assets of an organisation, such as its high-technology, complex systems, typically have long life-cycles, and are susceptible to obsolescence, requiring multifaceted support. Implementing integrated logistic support principles in supporting such systems improves the organisation's bottom line and reduces the total ownership and life-cycle costs. The research consists of a literature review, a case study analysis, and a questionnaire. Die sake-omgewing verander voortdurend. Om 'n kompeterende voordeel te verkry benodig organisasies innoverende metodes om toekomstige besigheidsdoelwitte te behaal. Die kapitaalbates van 'n organisasie, soos hoë-vlak tegnologie en komplekse stelsels het tipies lang leefsiklusse en is geneig om te verouder, wat veelsydige ondersteuning vereis. Die implementering van logistiese ondersteuningsbeginsels in sulke stelsels verbeter die organisasie se winsgrens en verminder die totale eienaarskap- en leefsikluskostes. Hierdie navorsing bestaan uit 'n literatuurstudie, 'n gevallestudie analise en 'n meningsopname vraelys.