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This paper discusses the development of a satellite-like system to bridge the gap between satellite development and satellite flight missions. The solution takes the form of a bench satellite, BenchSat, that can emulate satellite capabilities and interactions in a controlled environment on the ground. BenchSat utilises surrounding facilities, particularly an air bearing facility and an existing ground station, to produce a realistic test environment for satellite development. The air bearing facility entails a cart with pressurised gas which pushes the cart on a flat surface, creating a low-friction, space like environment. BenchSat comprises an electrical power subsystem, a radio communication subsystem, and an onboard computer subsystem. These systems are created to be a good representation of equivalent flight models and can serve as an initial step in the future development of each of these subsystems. A final experiment was conducted using an integrated BenchSat connected to an air bearing carrier cart. The ground station was used to give commands to the BenchSat to use its thrusters to translate and rotate the carrier cart. This creates a realistic interface to perform satellite rendezvous experiments. It is further extended to interface with a satellite simulator for Hardware-In-Loop testing and flight software development.

This study aims to explore the role of a doctoral supervisor in doctoral candidates' state of methodological preparedness within a specific disciplinary and institutional context. The number of doctoral graduates per million is commonly used as an indicator of progress to high-level competence and growth, and has become a global policy priority. The throughput rate of doctoral candidates is closely associated with their methodological preparedness, for which doctoral supervision is one of the key antecedents. While several studies have explored supervisory qualities as perceived and experienced by doctoral candidates, the supervisor's role, as perceived and experienced by supervisors themselves, appears to be under-researched. This study aims to provide a deeper understanding of this role from both the supervisors' and doctoral candidates' perspectives. This study departed from the view that researchers and participants share the world of doctoral supervision. Hence, we used phenomenology as an approach to the world of doctoral supervision, employing the Interpretive Phenomenological Analysis (IPA) method to understand how doctoral supervisors and candidates make sense of their lived experiences of doctoral supervision. We deliberately decided against survey studies as used in related studies. Although previous research utilised the 'voyage by ocean' metaphor concerning doctoral education, this study extends the discourse by applying an interpretive phenomenological design to provide a rich description of the supervisor's role as a coastguard within the context of an open distance learning institution. Doctoral supervisors perform a coastguard role in ensuring that candidates meet the regulatory requirements for their doctoral voyage, are timeously rescued and supported during their voyage, receive the necessary navigation assistance to reach their destinations, and are cared for in a humanitarian way. We recommend that a similar study be conducted on a large scale and in different contexts to further inform the enhancement of doctoral candidates' methodological preparedness.

An order picking system in a distribution centre consisting of parallel unidirectional picking lines is considered. The objectives are to minimise the walking distance of the pickers, the largest volume of stock on a picking line over all picking lines, the number of small packages, and the total penalty incurred for late distributions. The problem is formulated as a multi-objective multiple knapsack problem that is not solvable in a realistic time. Population-based algorithms, including the artificial bee colony algorithm and the genetic algorithm, are also implemented. The results obtained from all algorithms indicate a substantial improvement on all objectives relative to historical assignments. The genetic algorithm delivers the best performance.

An order picking system consisting of a number of parallel unidirectional picking lines is investigated. Stock keeping units (SKUs) that are grouped by product type into distributions (DBNs) are assigned daily to available picking lines. A mathematical programming formulation and its relaxations is presented. A greedy insertion and a greedy phased insertion are further introduced to obtain feasible results within usable computation times for all test cases. The walking distance of the pickers was shown to decrease by about 22 per cent compared with the current assignment approach. However, product handling and operational risk increases.

The order picking process is often the single largest expense in a distribution centre (DC). The DC considered in this paper uses a picking line configuration to perform order picking. The number of pickers in a picking line, and the initial arrangement of stock-keeping units (SKUs), are two important factors that affect the total completion time of the picking lines. In this paper, the picking line configuration is simulated with an agent-based approach to describe the behaviour of an individual picker. The simulation is then used to analyse the effect of the number of pickers and the SKU arrangement. Verification and validation of this model shows that the model represents the real-world picking line to a satisfactory degree. Marginal analysis (MA) was chosen to determine a ‘good’ number of pickers by means of the simulation model. A look-up table is presented to provide decision support for the choice of a ‘good’ number of pickers to improve completion times of the picking line, for the properties of a specific picking line. The initial SKU arrangement on a picking line is shown to be a factor that can affect the level of picker congestion and the total completion time. The greedy ranking and partitioning (GRP) and organ pipe arrangement (OPA) techniques from the literature, as well as the historical SKU arrangements used by the retailer under consideration, were compared with the proposed classroom discipline heuristic (CDH) for SKU arrangement. It was found that the CDH provides an more even spread of SKUs that are picked most frequently, thus decreasing congestion and total completion time.

An order picking system that requires pickers to move in a clockwise direction around a picking line with fixed locations is considered. The problem is divided into three tiers. The tier in which orders must be sequenced is addressed. Eight tour construction heuristics are developed and implemented for an order picking system operating in unidirectional picking lines. Two classes of tour construction heuristics the tour construction starting position ( ) and the tour construction ending position ( ) are developed to sequence orders in a picking line. All algorithms are tested and compared using real life data sets. The best solution quality was obtained by a heuristic with adaptations.

Abstract Motivation Ontology development and the annotation of biological data using ontologies are time-consuming exercises that currently require input from expert curators. Open, collaborative platforms for biological data annotation enable the wider scientific community to become involved in developing and maintaining such resources. However, this openness raises concerns regarding the quality and correctness of the information added to these knowledge bases. The combination of a collaborative web-based platform with logic-based approaches and Semantic Web technology can be used to address some of these challenges and concerns. Results We have developed the BOWiki, a web-based system that includes a biological core ontology. The core ontology provides background knowledge about biological types and relations. Against this background, an automated reasoner assesses the consistency of new information added to the knowledge base. The system provides a platform for research communities to integrate information and annotate data collaboratively. Availability The BOWiki and supplementary material is available at http://www.bowiki.net/. The source code is available under the GNU GPL from http://onto.eva.mpg.de/trac/BoWiki.

Abstract Background Anticancer research resulted in the discovery of a promising antimitotic metabolite, 2-methoxyestradiol. 2-Methoxyestradiol-bis-sulphamate, a bis-sulphamoylated analogue exerts antiproliferative- and antimitotic activity. Investigating the anticancer potential of 2-methoxyestradiol-bis-sulphamate requires demonstrating the influence of 2-methoxyestradiol-bis-sulphamate on non-tumorigenic cells. This project focused on the in vitro effects of 2-methoxyestradiol-bis-sulphamate on the non-tumorigenic MCF-12A breast epithelial cell line. Methods The in vitro influence of 2-methoxyestradiol-bis-sulphamate was investigated on cell cycle progression, possible induction of apoptosis and autophagy and reactive oxygen species generation. Cell cycle progression was done using flow cytometry in conjunction with ethanol fixation and propidium iodide staining. Displaying effects on the mitochondrial membrane potential was achieved utilizing flow cytometry and the MitoCapture TM Mitochondrial apoptosis detection kit. Autophagy detection was done by means of flow cytometry and anti-LC3B conjugated to DyLight 488. Reactive oxygen species generation was conducted employing flow cytometry and 2,7-dichlorofluorescein diacetate and hydroethidine. Results This study demonstrated that 2-methoxyestradiol-bis-sulphamate did not affect cell cycle progression or reactive oxygen species in a statistically significant manner in the non-tumorigenic MCF-12A cell line. In addition, 2-methoxyestradiol-bis-sulphamate did not statistically significantly induce apoptosis or autophagy. Conclusion Reports indicate that 2-methoxyestradiol-bis-sulphamate induces apoptosis and autophagy in several tumorigenic cell lines. The anticancer ability of 2-methoxyestradiol-bis-sulphamate is due to its antimitotic activity. However, this study demonstrates the promising notion that 2-methoxyestradiol-bis-sulphamate does not affect the non-tumorigenic MCF-12A cells. This project contributes to the embedded scientific knowledge regarding the differential death mechanisms used by 2-methoxyestradiol-bis-sulphamate on tumorigenic and non-tumorigenic cell lines.

Abstract Background In the search for anticancer agents, a promising 17-β-estradiol metabolite, 2-methoxyestradiol (2ME2) was found that exerts antiproliferative in vitro and in vivo activity. Since 2ME2 has limited biological accessibility and rapid metabolic degradation, the purpose of this study was to investigate the in vitro influence exerted by an analogue of 2ME2 namely 2-methoxyestradiol-bis-sulphamate (2MEBM) in a breast adenocarcinoma cell line (MCF-7). Methods This was conducted by investigating 2MEBM's in vitro influence on cell cycle progression, mitochondrial membrane potential and possible production of reactive oxygen species (ROS) generation. In vitro effects of 2MEBM on cell cycle progression was demonstrated by means of flow cytometry using propidium iodide. Hydrogen peroxide and superoxide production was investigated using 2,7-dichlorofluorescein diacetate and hydroethidine, respectively. The probable reduction in the mitochondrial membrane potential was demonstrated using a MitoCapture™ kit. Results Cell cycle progression revealed the presence of a sub-G1 apoptotic peak. Reduction of mitochondrial membrane potential after exposure to 2MEBM was demonstrated and an increase in ROS production was also observed. Conclusion This study verified that 2MEBM exposure resulted in apoptosis induction, increased ROS production and reduced mitochondrial membrane potential in a tumorigenic breast epithelial cell line. Data obtained from this project contributes to the unravelling of the in vitro signal transduction of 2MEBM in tumorigenic cell lines.

Recent publications have argued that there are potentially serious consequences for researchers in recognising distinct genera in the terminal fusarioid clade of the family Nectriaceae. Thus, an alternate hypothesis, namely a very broad concept of the genus Fusarium was proposed. In doing so, however, a significant body of data that supports distinct genera in Nectriaceae based on morphology, biology, and phylogeny is disregarded. A DNA phylogeny based on 19 orthologous protein-coding genes was presented to support a very broad concept of Fusarium at the F1 node in Nectriaceae. Here, we demonstrate that re-analyses of this dataset show that all 19 genes support the F3 node that represents Fusarium sensu stricto as defined by F. sambucinum (sexual morph synonym Gibberella pulicaris). The backbone of the phylogeny is resolved by the concatenated alignment, but only six of the 19 genes fully support the F1 node, representing the broad circumscription of Fusarium. Furthermore, a re-analysis of the concatenated dataset revealed alternate topologies in different phylogenetic algorithms, highlighting the deep divergence and unresolved placement of various Nectriaceae lineages proposed as members of Fusarium. Species of Fusarium s. str. are characterised by Gibberella sexual morphs, asexual morphs with thin- or thick-walled macroconidia that have variously shaped apical and basal cells, and trichothecene mycotoxin production, which separates them from other fusarioid genera. Here we show that the Wollenweber concept of Fusarium presently accounts for 20 segregate genera with clear-cut synapomorphic traits, and that fusarioid macroconidia represent a character that has been gained or lost multiple times throughout Nectriaceae. Thus, the very broad circumscription of Fusarium is blurry and without apparent synapomorphies, and does not include all genera with fusarium-like macroconidia, which are spread throughout Nectriaceae (e.g., Cosmosporella, Macroconia, Microcera). In this study four new genera are introduced, along with 18 new species and 16 new combinations. These names convey information about relationships, morphology, and ecological preference that would otherwise be lost in a broader definition of Fusarium. To assist users to correctly identify fusarioid genera and species, we introduce a new online identification database, Fusarioid-ID, accessible at www.fusarium.org. The database comprises partial sequences from multiple genes commonly used to identify fusarioid taxa (act1, CaM, his3, rpb1, rpb2, tef1, tub2, ITS, and LSU). In this paper, we also present a nomenclator of names that have been introduced in Fusarium up to January 2021 as well as their current status, types, and diagnostic DNA barcode data. In this study, researchers from 46 countries, representing taxonomists, plant pathologists, medical mycologists, quarantine officials, regulatory agencies, and students, strongly support the application and use of a more precisely delimited Fusarium (= Gibberella) concept to accommodate taxa from the robust monophyletic node F3 on the basis of a well-defined and unique combination of morphological and biochemical features. This F3 node includes, among others, species of the F. fujikuroi, F. incarnatum-equiseti, F. oxysporum, and F. sambucinum species complexes, but not species of Bisifusarium [F. dimerum species complex (SC)], Cyanonectria (F. buxicola SC), Geejayessia (F. staphyleae SC), Neocosmospora (F. solani SC) or Rectifusarium (F. ventricosum SC). The present study represents the first step to generating a new online monograph of Fusarium and allied fusarioid genera (www.fusarium.org).

Seven new genera, 26 new species, 10 new combinations, two epitypes, one new name, and 20 interesting new host and / or geographical records are introduced in this study. New genera are: Italiofungus (based on Italiofungus phillyreae) on leaves of Phillyrea latifolia (Italy); Neolamproconium (based on Neolamproconium silvestre) on branch of Tilia sp. (Ukraine); Neosorocybe (based on Neosorocybe pini) on trunk of Pinus sylvestris (Ukraine); Nothoseptoria (based on Nothoseptoria caraganae) on leaves of Caragana arborescens (Russia); Pruniphilomyces (based on Pruniphilomyces circumscissus) on Prunus cerasus (Russia); Vesiculozygosporium (based on Vesiculozygosporium echinosporum) on leaves of Muntingia calabura (Malaysia); Longiseptatispora (based on Longiseptatispora curvata) on leaves of Lonicera tatarica (Russia). New species are: Barrmaelia serenoae on leaf of Serenoa repens (USA); Chaetopsina gautengina on leaves of unidentified grass (South Africa); Chloridium pini on fallen trunk of Pinus sylvestris (Ukraine); Cadophora fallopiae on stems of Reynoutria sachalinensis (Poland); Coleophoma eucalyptigena on leaf litter of Eucalyptus sp. (Spain); Cylindrium corymbiae on leaves of Corymbia maculata (Australia); Diaporthe tarchonanthi on leaves of Tarchonanthus littoralis (South Africa); Elsinoe eucalyptorum on leaves of Eucalyptus propinqua (Australia); Exophiala quercina on dead wood of Quercus sp., (Germany); Fusarium californicum on cambium of budwood of Prunus dulcis (USA); Hypomyces gamsii on wood of Alnus glutinosa (Ukraine); Kalmusia araucariae on leaves of Araucaria bidwillii (USA); Lectera sambuci on leaves of Sambucus nigra (Russia); Melanomma populicola on fallen twig of Populus canadensis (Netherlands), Neocladosporium syringae on branches of Syringa vulgarishorus (Ukraine); Paraconiothyrium iridis on leaves of Iris pseudacorus (Ukraine); Pararoussoella quercina on branch of Quercus robur (Ukraine); Phialemonium pulveris from bore dust of deathwatch beetle (France); Polyscytalum pinicola on needles of Pinus tecunumanii (Malaysia); Acervuloseptoria fraxini on Fraxinus pennsylvanica (Russia); Roussoella arundinacea on culms of Arundo donax (Spain); Sphaerulina neoaceris on leaves of Acer negundo (Russia); Sphaerulina salicicola on leaves of Salix fragilis (Russia); Trichomerium syzygii on leaves of Syzygium cordatum (South Africa); Uzbekistanica vitis-viniferae on dead stem of Vitis vinifera (Ukraine); Vermiculariopsiella eucalyptigena on leaves of Eucalyptus sp. (Australia).

This article discusses and contrasts the measures of association introduced by Pearson, Spearman, and Kendall, as these are the three most commonly used in practice and also the ones primarily covered in introductory statistics courses. Emphasis is placed on concepts pertaining to the measurement of the level of association between two variables, the calculation of the coefficients, and the interpretation of the calculated values. In particular, we demonstrate how Spearman's rho and Kendall's tau can be expressed in terms of Pearson's correlation coefficient based on transformed data. Important concepts and potential pitfalls are illustrated using numerical examples.

Introduction: Anxiety is the most common psychological problem reported among children with visual impairments. Although cognitive behavior therapy interventions have proven successful in treating childhood anxiety, it is unclear whether they are suitable and accessible for children who have visual impairments. This study aimed to determine if and how traditional cognitive behavior therapy--based interventions could be adapted for use with this specific population by interviewing children with visual impairments themselves. Methods: A qualitative research design was used. Sixteen children with visual impairments (aged 9 to 13 years) participated in two focus group interviews. Participants attended two special schools in the Western Cape, South Africa. Interviews were audio-recorded and transcribed verbatim, and content analysis was undertaken. Results: Three primary themes emerged from the focus group data: (1) difficulties encountered by children with visual impairments; (2) existing coping strategies; and (3) insight into the concepts of feelings, thoughts and behaviors (central to cognitive behavior therapy). Discussion: The emergent themes and their implications for the adaptation of a cognitive behavior therapy--based anxiety intervention are discussed. Implications for practitioners: Results provide practitioners with guidelines to consider when using or adapting therapeutic techniques such as cognitive behavior therapy for children with visual impairments.

The end of each decade of democracy has seen periods of reflection in the South African visual art world through numerous initiatives, especially exhibitions and book publications. In 2024, after 30 years of democracy, the field is poised for another such moment of introspection. This article considers the first decade of democracy from the perspective of writing in the art world. Through a Constructivist Grounded Theory Method extant text analysis, a reading is conducted across various prominent South African art publications reflecting on the first decade, and these texts are coded to discern the major categories, or themes, that emerge through them, thereby distilling the period’s main features and concerns for influential writers and thinkers in the field at the time as themes. These include, (1) emerging onto the international art scene after the boycott, (2) navigating international demands and local challenges, (3) government failures, (4) presuming equality under democracy and globalism, (5) race and the persistence of white dominance, (6) challenging Western- and Eurocentricism, (7) questioning visual arts education, (8) lacking engagement with art, (9) questions around moving on from resistance art, (10) negotiating and representing identity, and (11) the rise and critique of the gallery system. Not only are the major concerns and their textures succinctly revealed through the rigorous Grounded Theory Method coding process, but their crystallisation also deepens our understanding of how the art world has interacted with the periods of democracy, and which particular sets of preoccupations have informed its discourses. [ABSTRACT FROM AUTHOR]

Teaching and assessment practices rapidly moved online as a result of the global coronavirus pandemic. Academic integrity is paramount for the credibility and reputation of educational institutions regardless of their teaching modality. Students commit plagiarism when they copy, borrow, or steal others' work, without properly acknowledging their source(s). Especially in online environments, accounting students frequently fall prey to plagiarism and, as a result, transgress the fundamental values of integrity and honesty that should be deep-rooted in accountants. It is, therefore, critical that educators increase their students' plagiarism awareness and understanding. Drawing on the findings of conceptual, literature review-based research, the Biological Sciences Curriculum Study 5E (BSCS 5E) instructional model is applied as a frame of reference for accounting educators to promote their students' awareness of plagiarism while concomitantly enhancing their twenty-first-century skills. Both theoretical and practical contributions are envisaged through the application of this constructivist, student-centred approach.