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A domain ontology for gait analysis and decision support on gait-related diseases
No full textThe complexity of diagnosing and treating gait-related diseases necessitates the existence of a domain ontology that can support intelligent decision-making by gait experts and medical personnel. This study describes the development of a domain ontology for gait analysis and decision support on gait-related diseases. The process for developing the ontology followed a custom ontology development process that is based on the hybridisation of the Ontology 101 (OD-101) development methodology and Methontology, ensuring a systematic and replicable construction of the ontology. The design of the Gait Analysis Domain Ontology (GADO) embraced thirteen dimensions, making it the most comprehensive domain ontology for gait analysis compared to previous efforts. The GADO was created using the Protégé ontology editor and was evaluated by using ontology verification and validation procedures. Ontology verification was conducted by using the Framework for Ontology Conformance Analysis (FOCA) to assess domain task fit through competency questions and content richness of the ontology. The results demonstrated GADO’s suitability in representing the domain effectively. Ontology validation involved checking the structural and logical consistency of the ontology by using reasoners such as HermiT and Pellet and employing Description Logic and SPARQL queries to assess the ontology’s ability to respond to domain-specific queries accurately. The validation process confirmed the GADO’s effectiveness in facilitating the retrieval of relevant information. Thus, the GADO is positioned to enhance clinical decision support for gait-related diseases, thereby advancing the applications of ontology-enabled decision support systems
Relative Expression of a Salinity Stress-Responsive Na+/H+ Exchanger (NHX) in Root and Leaf Tissues of the African Leafy Vegetable, Amaranthus dubius
No full textAmaranthus dubius, an African leafy vegetable (ALV), is an easy-to-grow, annual shrub and a highly nutritious food source, containing elevated levels of essential nutrients in the leaves. Many ALVs, including A. dubius, can tolerate salinity stress, enabling their cultivation on marginal land. However, the widespread propagation of A. dubius as a stable food source has thus far not been realised due partially to the high frequency at which hybridisation occurs, resulting in high genotypic and phenotypic variability. Therefore, to increase the agricultural output capacity of this species on salt-affected marginal lands, it is important to screen, select and then clonally propagate the identified salinity-tolerant genotypes to ensure true-to-type fidelity in the regenerated population. It is also important, thereafter, to elucidate their underlying gene expression of the stress response. The present study exposed 4-week-old A. dubius seedlings to 100, 200 and 400 mM NaCl to determine their degree of salt tolerance. Genotypes were then screened, selected and clonally propagated through cuttings, based on high growth rates and biomass, and salt tolerance. Generally, growth and physiological parameters decreased as substrate salinity increased. However, individual salt-stressed genotypes demonstrated similar vigour to nonstressed plants and were able to maintain total protein and chlorophyll concentrations despite increasing salinity. The relative expression of an NHX1-like transcript was quantified in 15 genotypes using degenerately primed real-time qPCR. The relative expression of the putative NHX1 gene was 6.7 times greater in root tissues of seedlings treated with 400 mM NaCl (10.7 ± 1.8) compared to the roots of untreated seedlings (1.6 ± 1.3), and 2.8-fold more than leaf tissues harvested from seedlings treated with 400 mM NaCl. Furthermore, the relative electrical conductivity (EC) of root tissues was 10 times greater than the EC of leaf tissues from the same 400 mM NaCl treatment. Numerous genotypes yielded similar chlorophyll content between 200 and 400 mM NaCl treatments, with genotypes salinity-1 (S1) (3.5 ± 0.2 μg/cm2) and S34 (4.0 ± 0.4 μg/cm2) having the highest concentrations of chlorophyll in the 400 mM group, which was positively correlated with total protein content. Following micropropagation through direct organogenesis, selected clones maintained true-to-type traits such as similar chlorophyll, protein and NHX1-like expression as their parent plants when exposed to 400 mM NaCl. This study revealed that some genotypes demonstrated salt stress tolerance capabilities rivalling established halophytes by regulating the constitutive or inducible expression of an NHX1-like protein in roots and leaves. The correlation between protein content and NHX1-like expression was nonlinear and nonproportional, demonstrating the complexity of this response and necessitating further exploration of specific protein families or functional groups conferring salinity tolerance in this species
Cervical inspection with AAVI and cryotherapy on HPV-diagnosed women in Windhoek, Namibia
No full textIn 2018, the Ministry of Health and Social Services (MoHSS) introduced acetic acid visual inspection (AAVI) screening program and treatment of cervical precancers with cryotherapy in replacement of Pap smear intervention in Namibia. The study examines the effective use of AAVI-and-cryotherapy treatment on HPV-diagnosed women. Female patients of the reproductive age (20-49 years) group visiting 2 Namibian healthcare facilities for AAVI and cryotherapy treatment were investigated using a cross-sectional approach. The SPSS and coding themes were used to analyze data received through questionnaires and face-to-face interviews from a total of 265 participants. Written informed consent was obtained from participants for treatment and for publication. Among the women that participated in the study, 151 (62%) tested HPV positive, of which 132 (53%) were referred for cryotherapy and 19 (8%) for colposcopy treatments due to Cervical Intraepithelial Neoplasia (CIN I-III) detected. Regardless of the age groups, there was significant evidence of an association between para gravida and HPV positive (χ2(6) = 24.518; P < .001) and HPV negative (χ2(18) = 137.098; P < .001). About 80% of all participants experienced unpleasant pelvic sensations during the examination, with slight abdominal pain during and after the procedure. Ten percent experienced brownish discharges from their pelvis, of which was treated during the cryotherapy treatment. These findings suggest that MoHSS should actively re-evaluate the existing policies to promote AAVI and cryotherapy treatment
Investigating the altered expression of miR-486-5p and miR-novel-chr1_40444 in dysglycemia in a South African population
No full textAims: This study aims to investigate miR-486-5p and miR-novel-chr1_40444 expressions
in dysglycemic individuals. Validating RNA-sequencing findings in a larger sample via
reverse transcription qPCR (RT-qPCR), we aim to address global diagnostic and screening
limitations, using an African cohort as an example.
Materials and Methods: This cross-sectional study involved 1,271 individuals
[normoglycemic (n = 974), prediabetic (n = 206), screen-detected type 2 diabetes (n = 91)]
from the ongoing Vascular and Metabolic Health (VMH) study in Cape Town, South Africa.
Whole blood miRNA expression was assessed using TaqMan-based RT-qPCR, with data
normalized to an endogenous control (miR-16-5p).
Results: Significant underexpression was observed in prediabetes vs normoglycemia for
miR-486-5p (P = 0.038), whilst both miRNAs demonstrated significant upregulation in
screen-detected type 2 diabetes vs normoglycemia (miR-486-5p, P = 0.009; miR-novel chr1_40444, P < 0.001), and screen-detected type 2 diabetes in comparison with
prediabetes (miR-486-5p, P < 0.001; miR-novel-chr1_40444, P < 0.001). Multivariable
regression analyses revealed pronounced interrelations between miR-novel-chr1_40444
and screen-detected type 2 diabetes in unadjusted and adjusted models (Model 1:
P < 0.001, Model 2: P < 0.001, Model 3: P = 0.030). Moreover, receiver operating
characteristic (ROC) curves revealed significantly enhanced diagnostic capabilities for
screen-detected type 2 diabetes vs either normoglycemia (AUC = 0.971, P < 0.001),
non-diabetes (AUC = 0.959, P < 0.001), or prediabetes (AUC = 0.902, P < 0.001) when
combining the miRNAs with 2 h postprandial glucose.
Conclusions: This study demonstrated the enhanced power of incorporating miRNAs
with traditional markers in distinguishing screen-detected type 2 diabetes, warranting
further investigations on their unique role in the development of type 2 diabetes
A critical review of systems for bioremediation of tannery effluent with a focus on nitrogenous and sulfurous species removal and resource recovery
No full textTanneries generate copious amounts of potentially toxic sludge and effluent from the processing of skins and hides to leather. The effluent requires remediation before discharge to protect the receiving environment. A range of physicochemical methods are used for pre- and post-treatment, but biological secondary remediation remains the most popular choice for the reduction of the organic and macronutrient fraction of tannery effluent. This review provides an update and critical discussion of biological systems used to remediate tannery effluent. While the conventional activated sludge process and similar technologies are widely used by tanneries, they have inherent problems related to poor sludge settling, low removal efficiencies, and high energy requirements. Treatment wetlands are recommended for the passive polishing step of beamhouse effluent. Hybrid systems that incorporate anoxic and/or anaerobic zones with sludge and/or effluent recycling have been shown to be effective for the removal of organics and nitrogenous species at laboratory scale, and some have been piloted. Novel systems have also been proposed for the removal and recovery of elemental sulfur and/or energy and/or process water in support of a circular economy. Full-scale studies showing successful long-term operation of such systems are now required to convince tanneries to modernize and invest in new infrastructure
Nuclear resilient and redundant compute and communication integrated network
No full textFuture communication networks use computing platforms i.e., data centers for enabling content access. The operation of data centers is evolving to meet new requirements such as reducing the operating cost. The use of data centers is recognized to have significant challenges due to high operating costs. The high operating costs arises due to the necessity of data center cooling. The cooling costs can be reduced by siting data centers in the underwater environment. In the underwater environment, data centers are cooled by freely available cold water. However, siting data centers in the underwater environment exposes them to risk from other underwater applications. The use of underwater data centers is susceptible to service loss due to the launch of missiles from submarines in defense applications. Underwater data centers are susceptible to service loss from the launch of missiles from submarines. Hence, it is necessary to design a network architecture that ensures continued service delivery when nuclear attacks occur. The presented research proposes a novel network architecture enabling service continuity in the underwater data center. The proposed architecture incorporates resiliency and comprises terrestrial and non–terrestrial data centers. The proposed network architecture incorporates redundancy and utilizes terrestrial and non-terrestrial data centers. In addition, the research presents a protocol enabling co-existence between underwater data centers and missile launching submarines used in defence applications. The research formulates and evaluates the operational duration, number of packets forwarding paths, and computing resource utilization as the metrics. Performance evaluation shows that the proposed network architecture improves the operational duration and computing resource utilization by an average of (27.7–71.5)% and (23.5–44.2)%, respectively. Furthermore, the proposed network architecture enables the realization of more resilient paths. The use of more resilient paths enhances packet transmission. Evaluation shows that the proposed network architecture enhances the number of resilient packets forwarding paths by (18.2–57.4)% on average
Fusarium and fumonisin in GM maize grown by small-scale farmers in KwaZulu-Natal, South Africa
No full textThe genetic modification (GM) of maize to contain proteins that act to control insects has become a widespread agricultural practice. Although the reduction of insect damage to maize ears could potentially increase crop yield, rural small-scale farmers might be reluctant to buy expensive GM seed every season even when the lower fungal infection of the GM maize might also result in health benefits. This study was conducted over 5 years in three districts of northern KwaZulu-Natal, South Africa, to study the Fusarium verticillioides and F. proliferatum infection and fumonisin contamination levels in Bt maize, Roundup- Ready® maize, conventional commercial maize and traditional landrace maize planted by rural farmers following their traditional agricultural practices. Mean Fusarium infection rates varied between 3.0% and 38.3% with large standard deviations. Fusarium infection was not significantly different (p>0.05) between the various genotypes, possibly due to the wide variation in results and low sample numbers. Although the fumonisin results also showed wide variation, the trend of contamination was lower in Bt maize compared to conventional commercial genotypes. The mean fumonisin levels in Bt hybrids were mostly <300 μg/kg, ensuring a safe maize supply in populations consuming maize as a dietary staple. The wide variations in Fusarium and fumonisin levels within each district point to the influence of local agricultural practices, local environmental conditions, and seasonal variations. Reducing exposure to fumonisins in these communities requires both further attention to the possible influence of these factors, as well as the use of appropriate post-harvest strategies
A Corporate Social Responsibility (CSR) Model to Achieve Sustainable Business Performance (SBP) of SMEs in the South African Construction Industry
No full textThis paper purposes to develop a corporate social responsibility (CSR) model to guide small and medium enterprises (SMEs) in the South African construction industry (SACI) towards sustainable business performance (SBP). A theoretical CSR model was developed from the literature and validated through Partial Least Squares Structural Equation Modelling (PLS-SEM), using primary questionnaire data obtained from 110 SMEs in the SACI, who are registered on the construction industry development board (cidb) register of contractors between Grade 1 and 6 general building (GB) and/or civil engineering (CE). The PLS-SEM results indicate that CSR drivers influencing the CSR practices of SMEs, along with CSR implementation challenges experienced by SMEs, influence the perception of SMEs pertaining to the relationship between the integration of CSR and SBP all of which influences the CSR activities considered by SMEs to achieve SBP, thus implying that the holistic adaption of the PLS-SEM (CSR model) by SMEs in the SACI equates to more SBP. However, SMEs practicing CSR activities to achieve SBP are subjected to specific CSR: drivers and implementation challenges as well as SME owner perceptions
Demand-side management as a network planning tool: review of drivers, benefits and opportunities for south Africa
No full textThe reliability and security of an electric power supply have become pivotal to the proper functioning of modern society. Traditionally, the electric power supply system has been designed with the objective of being able to adequately meet present and future demand, with efforts to maintain supply reliability being focused primarily on the supply side. Over the decades, however, the value of demand-side management—efforts focused on enhancing the efficient and effective use of electricity in support of the power system and customer needs—has been widely acknowledged as being able to play a greater role in ensuring that the key objectives of power system operation are satisfied. This article presents a study of demand-side management and opportunities for incorporating it into network planning as an effective means of addressing supply capacity constraints in the South African electric grid. The main drivers, benefits and potential barriers to the effective implementation of demand-side management are examined, along with the main enabling technologies. The key finding of the study is that the effective integration of demand-side management into network planning requires a shift from the traditional network planning approach to one that is more suited to fully exploiting the flexibility resources available on the demand side of the network
Battery storage use in the value chain of power systems
No full textIn recent years, energy challenges such as grid congestion and imbalances have emerged from conventional electric grids. Furthermore, the unpredictable nature of these systems poses many challenges in meeting various users’ demands. The Battery Energy Storage System is a potential key for grid instability with improved power quality. The present study investigates the global trend towards integrating battery technology as an energy storage system with renewable energy production and utility grid systems. An extensive review of battery systems such as Lithium-Ion, Lead–Acid, Zinc–Bromide, Nickel–Cadmium, Sodium–Sulphur, and the Vanadium redox flow battery is conducted. Furthermore, a comparative analysis of their working principles, control strategies, optimizations, and technical characteristics is presented. The review findings show that Lead–Acid, Lithium-Ion, Sodium-based, and flow redox batteries have seen increased breakthroughs in the energy storage market. Furthermore, the use of the BESS as an ancillary service and control technique enhances the performance of microgrids and utility grid systems. These control techniques provide potential solutions such as peak load shaving, the smoothing of photovoltaic ramp rates, voltage fluctuation reduction, a large grid, power supply backup, microgrids, renewable energy sources time shift, spinning reserve for industrial consumers, and frequency regulation. Conclusively, a cost summary of the various battery technologies is presented