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Current state of practice for the assessment of liquefied strengths of tailings relies primarily on empirical or semi-empirical correlations based on penetration testing. That is, despite liquefied strength being arguably the most important strength parameter for the design of brittle tailings storage facilities, there is much less success or acceptance of the use of laboratory element tests to support strength selection compared to other forms of strengths inferred in geotechnical engineering. This is particularly the case for tailings at a state near or slightly dense of the critical state line (CSL) for which there is ample evidence of field-scale flow liquefaction but where laboratory element tests often behave in a manner inconsistent with such field-scale response – at least at large strains. The current paper examines the quasi steady state (QSS) strength of sands and tailings for which the CSL has been measured, linking the observed strengths to inferred in situ behaviour through the state parameter. Particular focus is placed on QSS strengths obtained from simple shear tests carried out within a hollow cylinder torsional shear system where the stress state in the test is a better representation of in situ below-slope conditions that the triaxial compression test. In particular, the marked effect of intermediate principal stress on the QSS in sands is highlighted. Alternatively, the negligible anisotropy seen in a sandy silt gold tailings, and the potential implications in the context of QSS strengths and field-scale behaviour, are examined and emphasised.

For a soil that is contractive and strain softening at fully saturated conditions the question remains on which degree of saturation can trigger a strain softening response. A common engineering practice is to adopt a saturation threshold (e.g., 85%) and then assume a fully saturated response when saturation is above that value. This study aims to understand how the strain softening response change when tailings are not fully saturated and to propose a systematic method for determining the saturation threshold. A restraint when preparing unsaturated loose samples is that it is likely to have collapse during flashing, thus changing void ratio and making comparisons between different degrees of saturation problematic. A simple procedure to obtain loose samples at different degrees of saturation but at similar post-flushing void ratios is explained and preliminary results of undrained shear strength obtained for gold tailings in triaxial device are presented and discussed.

Laboratory-controlled cone penetration test results of a silty gold tailings in a variety of saturated and unsaturated states, obtained using two calibration chambers, are presented then interpreted using a state parameter-based approach. The research was conducted as part of the TAILLIQ project (tailliq.com), funded by the Australian Research Council and six mining companies, and involving four Australian universities.Cone penetration resistances, which increase due to the presence of suction when the tailings are unsaturated, can be normalised using the initial mean effective stress to establish a relationship with the initial state parameter. The relationship is applicable to saturated and unsaturated conditions, as long as the presence of suction hardening as well as the influence of suction on the mean effective stress are accounted for, and as long as the cone penetrations occur under pseudo drained conditions. The relationships enable state parameters and void ratios to be back-calculated from normalised cone penetration resistances.

Water repellent (or “hydrophobic” or “non-wetting”) soils have been studied by soil scientists for well over a century. These soils are typified by poor water infiltration, which leads to increased soil erosion and poor crop growth. However, the importance of water repellence on determining soil properties is now becoming recognised by geotechnical engineers. Water repellent soils may, for example, offer novel solutions for the design of cover systems overlying municipal or mine waste storage facilities. However, investigations into factors affecting their mechanical properties have only recently been initiated. This purpose of this paper is to introduce geotechnical engineers to the concept of water repellent soils and to discuss how their properties can be evaluated under an unsaturated soils framework. Scenarios in which water repellent properties might be relevant in geotechnical applications are presented and methods to quantify these properties in the laboratory and in the field examined.

Abstract Background In cattle, genome-wide association studies (GWAS) have largely focused on European or Asian breeds, using genotyping arrays that were primarily designed for European cattle. Because there is growing interest in performing GWAS in African breeds, we have assessed the performance of 23 commercial bovine genotyping arrays for capturing the diversity across African breeds and performing imputation. We used 409 whole-genome sequences (WGS) spanning global cattle breeds, and a real cohort of 2481 individuals (including African breeds) that were genotyped with the Illumina high-density (HD) array and the GeneSeek bovine 50 k array. Results We found that commercially available arrays were not effective in capturing variants that segregate among African indicine animals. Only 6% of these variants in high linkage disequilibrium (LD) (r2 > 0.8) were on the best performing arrays, which contrasts with the 17% and 25% in African and European taurine cattle, respectively. However, imputation from available HD arrays can successfully capture most variants (accuracies up to 0.93), mainly when using a global, not continent-specific, reference panel, which partially reflects the unusually high levels of admixture on the continent. When considering functional variants, the GGPF250 array performed best for tagging WGS variants and imputation. Finally, we show that imputation from low-density arrays can perform almost as well as HD arrays, if a two-stage imputation approach is adopted, i.e. first imputing to HD and then to WGS, which can potentially reduce the costs of GWAS. Conclusions Our results show that the choice of an array should be based on a balance between the objective of the study and the breed/population considered, with the HD and BOS1 arrays being the best choice for both taurine and indicine breeds when performing GWAS, and the GGPF250 being preferable for fine-mapping studies. Moreover, our results suggest that there is no advantage to using the indicus-specific arrays for indicus breeds, regardless of the objective. Finally, we show that using a reference panel that better represents global bovine diversity improves imputation accuracy, particularly for non-European taurine populations.

The aim of this article is to explore the power relations portrayed through the bodily spatial interaction of the characters of Milla and Agaat in Marlene van Niekerk’s 2004 novel, Agaat. This interaction is analysed according to the theory of Thirding-asOthering posited by Henri Lefebvre and Edward Soja in terms of the body in space. The body in space is interpreted through agency which is exemplified in the intimacy of the relations of these two bodies through the actions of bathing, giving birth, and the physical aspects of the process of “civilising” the child character of Agaat. Through an analysis of three sets of incidents and scenes which illustrate the physical inhabitation of space through agency, the power relations between Milla and Agaat are exemplified and discussed. The analysis culminates in the conclusion that the relationship between Milla and Agaat is a cyclical power play that does not come to any pure form of dominance or submission because of the inhabitation that they enact through each other. With agency being tantamount to inhabitation and assertion of power, Agaat has the ultimate power on the farm through Milla, as Milla’s body is othered by her illness and finally her death.

Résumé: Les auteurs analysent la façon dont le cadre du droit du travail s'est constitué dans les pays de la Communauté de développement de l'Afrique australe (SADC), en cherchant à faire apparaître les cas de segmentation juridique. En parallèle, ils donnent un aperçu des caractéristiques démographiques de l'économie informelle dans les pays en question. Ils concluent que, par les mécanismes qu'il met en œuvre dans la région, le droit du travail contribue dans une large mesure à la segmentation économique qu'on peut y observer, et ce alors même que les principes qu'il promeut ont été inscrits dans les constitutions des pays en question. [ABSTRACT FROM AUTHOR]

ABSTRACT: A learner's corpus is a body of writing for use by a student whose first language is not (in this case) English to improve his/her use of (in this case) academic scientific terminology. In this case study, a learner's corpus was developed for a first-year mathematics module for students in the biological sciences. Lecturers struggle with big classes and a fairly high failure rate which they have addressed in a variety of ways. The learner's corpus is one of an array of support mechanisms built into the teaching-learning process and aims to support the development of academic literacy in this module in particular. In the process of developing and refining this learner's corpus it was compared to Coxhead's Academic Word List to determine whether a gen-eral academic word list may not include enough terms to render tailor-made learner's corpora unnecessary. The study concludes that the most frequent terms used in this module either do not appear in the Academic Word List or have such a specialised meaning that general academic sup-port on the basis of the word list would probably not be very useful for students.Keywords: LEARNER'S CORPUS, ACADEMIC WORD LIST, ACADEMIC LANGUAGE SUPPORT, MATHEMATICS WORD LIST, PEDAGOGIC APPLICATION OF CORPORA, CASE STUDY*****OPSOMMING: Die ontwikkeling van 'n leerderskorpus: Die geval van 'n eer-stejaarswiskundemodule. 'n Leerderskorpus is 'n versameling tekste vir gebruik deur 'n student wie se eerste taal nie (in hierdie geval) Engels is nie, om sy/haar gebruik van (in hierdie geval) akademiese wetenskaplike terminologie te verbeter. In hierdie gevallestudie is 'n leerders-korpus ontwikkel vir 'n eerstejaarswiskundemodule vir studente in die biologiese wetenskappe. Dosente sukkel met groot klasse en 'n redelik hoë druipsyfer, wat hulle op verskillende maniere benader het. Die leerderskorpus is een van 'n reeks ondersteuningsmeganismes wat in die onder-rig-leer-proses ingebou is en beoog om die ontwikkeling van akademiese geletterdheid spesifiek in hierdie module te ondersteun. Tydens die ontwikkeling en verfyning van die leerderskorpus is dit vergelyk met Coxhead se Academic Word List om vas te stel of hierdie woordelys nie genoeg terme insluit om maatpas leerderskorpusse oorbodig te maak nie. Die studie kom tot die gevolg-trekking dat die frekwentste terme wat in hierdie module gebruik word óf nie in die Academic Word List voorkom nie óf so 'n gespesialiseerde betekenis het dat algemene akademiese hulp op grond van die woordelys waarskynlik nie vir studente baie nuttig sal wees nie.Sleutelwoorde: LEERDERSKORPUS, AKADEMIESE WOORDELYS, AKADEMIESE TAAL-HULP, WISKUNDEWOORDELYS, OPVOEDKUNDIGE TOEPASSING VAN KORPUSSE, GE-VALLESTUDIE

Background: Point-of-care ultrasound (POCUS) improves patient outcomes. The current POCUS curriculum of the Emergency Medicine Society of South Africa is based on guidelines from the United Kingdom with a different burden of disease (BoD) and available resources than encountered locally. Aim: To determine which modules of the POCUS curriculum should be implemented to better equip doctors working at a district hospital in the West Coast District (WCD), South Africa. Setting: Six district hospitals within the WCD. Methods: A descriptive cross-sectional survey with questionnaires for medical managers (MMs) and medical practitioners (MPs). Results: A response rate of 78.9% for MPs and 100% for MMs was obtained. MPs rated the following modules of POCUS most relevant to their daily practice: (1) first trimester pregnancy; (2) deep vein thrombosis; (3) extended focused assessment with sonography in trauma; (4) central vascular access; and (5) focused assessment with sonography for human immunodeficiency virus (HIV) and tuberculosis (TB) (FASH). Conclusion: There is a need for a POCUS curriculum informed by the local pattern of disease. Priority modules were identified based on the local BoD and reported relevance to practice. Despite the availability of ultrasound machines within the WCD, few MPs were accredited and able to perform POCUS independently. There is a need to implement training programmes for medical interns, MPs, family medicine registrars and family physicians working in district hospitals. A relevant curriculum for POCUS training based on the local needs within communities has to be developed. Contribution: This study emphasises the need for a locally informed POCUS curriculum and training programmes.

Selective laser melting (SLM) employs the use of powder as the feedstock to manufacture the desired geometries in a layer-by-layer fashion. The part density of manufactured components is one factor used to evaluate part quality since the density has been shown to influence the mechanical properties of SLM components. This study investigated the effect of build location on the part density of selective laser melted CoCrMo. The results showed that the part density varied across the build platform due to the powder packing efficiency. The main role in the density variation is due to the inconsistent powder distribution and packing efficiency across the build plate, negatively affecting the part density.

Thermal inconsistencies inherent in the selective laser melting manufacturing process generate residual stress that may exceed the yield strength of the material resulting in deformation and cracking of components. This may however be mitigated through a stress-relief annealing process. The purpose of this study is to investigate the effect of stress-relief anneal time on the residual stress in selective laser melted Co-Cr-Mo components by means of simulation and neutron diffraction techniques. Thin-walled samples were manufactured and subjected to heat treatment at 1065°C for different holding times (0.25, 1, 2 and 3 hours) as well as a sample heat treated at 750°C for 1 hour. Evaluation of the residual stress reveals that the heat-treated samples have significantly lower residual stress as compared to an as-built (non-heat treated) control sample. Results indicate that the range of annealing times investigated produce near-identical residual stress values. Higher annealing temperatures however result in lower residual stresses. Comparison of simulated and neutron diffraction results indicate anisotropic behaviour of the material which can be attributed to the layer-wise addition of material.

Equivalent Relations in Bilingual Dictionaries: Implications for the Database of an Electronic Bilingual Dictionary of South African Sign Language and Afrikaans. This article is an extract from a more comprehensive theoretical framework in which a concept model for an electronic bilingual foundation phase dictionary of South African Sign Language and Afrikaans is suggested, specifically for the De la Bat School for the Deaf in Worcester, South Africa (Fourie 2013). The purpose of the proposed dictionary is to give the learners of the De la Bat School electronic access to written school word lists, with signs and examples in sign language displayed in video format — therefore in the form of an electronic dictionary. A written word list does not meet the needs of school learners in this case and a dictionary that is designed for the Deaf target users at the school will be of far greater value in the learners' communication in both sign language and the written language. Certain components of the model can in fact also be implemented by users other than the original target users, so that it may also be of use to the broader Deaf community. This article investigates the typical equivalent relations in bilingual dictionaries and on that basis the core of the article makes suggestions about how the lexicographer could treat equivalent relations between sign language and Afrikaans in the proposed dictionary.

Outer Texts in an Electronic Sign Language Dictionary.The suggestions made in this article about outer texts in an electronic sign language dictionary serve as part of a complete concept model suggested specifically for the De la Bat School for the Deaf in Worcester, South Africa (Fourie 2013). The purpose of the proposed dictionary is to give the learners of the De la Bat School electronic access to written school word lists, with signs and examples in sign language displayed in video format — therefore in the form of an electronic dictionary. A written word list does not meet the needs of school learners in this case and a dictionary that is designed for the Deaf target users at the school will be of far greater value in the learners' communication in both sign language and the written language.The article discusses data distribution and the use of a frame structure, the use of outer texts and also supplies examples of outer texts in existing sign language dictionaries, whether electronic or not. Following that suggestions for outer texts in the context of the model are made with illustrating examples.

Dictionaries and Deaf Users — Current Problems and the Need for Better Solutions. Sign language lexicography is a branch of lexicography that has until now been a largely vague, unimportant area. The development of sign language lexicography has in the past been subject to various forms of bias and limitation. Often it was not considered necessary to compile a bilingual dictionary in which it is also possible to look up a sign because bilingual sign language dictionaries were mostly aimed at hearing people who wanted to or had to learn the lan­guage. In addition to that it was very difficult, owing to the nature of printed dictionaries and the lack of a sign lan­guage orthography, to present and order signs so that they may be searched with­out using a writ­ten search term. Some notation systems were developed in an effort to circum­vent this problem, but these systems never found widespread acceptance with regular users. The devel­op­ment of electronic sign language dictionaries however have caused a revolution in sign language lexicography. It is no longer unusual to find electronic sign language dictionaries in which it is not only possible to search for a word, but also for a sign, usually according to one or more of the sign's parameters, like handshape. Such dictionaries make it possible for a Deaf user to obtain direct access to his or her first language (sign language) without any knowledge of the sec­ond language (the written language). The article also points out a newly proposed model for very young Deaf users which allows them to also search for a sign or word via concept.

Lien Botha is bekend as kunstenaar-fotograaf. Wonderboom, haar debuutroman, is die eindproduk van ’n magistergraad in Kreatiewe Skryfkuns. Met die publikasie van hierdie roman sluit Botha aan by ’n toenemende aantal skrywers en digters wat die Afrikaanse literêre landskap die laaste paar jaar op soortgelyke wyse betree het. Die verskillende kunstenaarsrolle wat Botha aanneem, blyk duidelik in Wonderboom, aangesien Botha se visuele kuns en ingesteldheid met gewaagdheid by die roman ingewerk word.

There has always been a need to monitor the near Earth's magnetic field, as this monitoring provides understanding and possible predictions of Space Weather events such as geomagnetic storms. Conventional magnetometers such as fluxgates have been used for decades for Space Weather research. The use of highly sensitive magnetometers such as Superconducting QUantum Interference Devices (SQUIDs), promise to give more insight into Space Weather. SQUIDs are relatively recent types of magnetometers that exploit the superconductive effects of flux quantization and Josephson tunneling to measure magnetic flux. SQUIDs have a very broad bandwidth compared to most conventional magnetometers and can measure magnetic flux as low as a few femtotesla. Since SQUIDs have never been used in Space Weather research, unshielded, it is necessary to investigate if they can be reliable Space Weather instruments. The validation is performed by comparing the frequency content of the SQUID and fluxgate magnetometers, as reported by Phiri.

SQUID magnetometers for geomagnetic research can only be used optimally if they are moved away from man-made interference. This leads to several problems related to infrastructure. This article briefly discusses current research involving issues with site selection, liquid nitrogen monitoring and transfer, and the use of Helmholtz coils for zero-field cooling and orientation.