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The Knowledge Landscape of Adenylyl Cyclases in Model Plant, Arabidopsis thaliana
Get PDFBook chapter,One strategy for improving responses and adaptation systems of plants to stress is to target molecules involved in signaling and transduction of the stimuli effected by stresses. One such molecule is adenylyl cyclase (AC) – an enzyme that catalyzes the conversion of adenosine 5′-triphosphate (ATP) to the second messenger, 3′,5′-cyclic adenosine monophosphate (cAMP). cAMP, in turn, transduces signals in response to the various biotic and abiotic stress factors. Surprisingly, as far as five decades ago, attempts to isolate ACs and/or detect cAMP from the research model plant, Arabidopsis thaliana, were inconclusive or a matter of serious debates due to the absence of appropriate techniques or advanced technologies. This chapter, therefore, herein takes the reader on a journey from the 1970s to the present day, unraveling the challenges encountered, developments made, and successes realized in efforts and attempts to identify and characterize ACs in A. thaliana. The chapter covers from the early age of unsuccessful attempts to the more recent and successful advanced technologies such as the motif search approach, omics analysis and homologous cloning. Perspectives on the direction that future knowledge-building around this important group of plant proteins are also shared.The project was funded by the National Research Foundation (NRF) of SouthAfrica (Grant Numbers: CSUR78843 & CSUR93635) and the Organization forWomen in Science for the Developing World (OWSD)
Twenty-four-hour ambulatory, but not clinic blood pressure associates with leptin in young adults with overweight or obesity: The African-PREDICT study
Get PDFHypertension in Africa Research Team (HART), North-West
University, Potchefstroom, South Africa
2 Medical Research Council: Research Unit for Hypertension and
Cardiovascular Disease, North-West University,
Potchefstroom, South Africa
3 Physical activity, Sport and Recreation (PhASRec), North-West
University, Potchefstroom, South AfricaHypertension and obesity are known pro-inflammatory conditions, and limited studies explored various blood pressure
modalities and inflammatory markers in young adults with overweight or obesity (OW/OB). We assessed the relationship of
clinic and 24 h ambulatory blood pressure with an array of inflammatory markers in young adults with OW/OB. This crosssectional study included women and men of Black and White ethnicity (n = 1194) with a median age of 24.5 ± 3.12 years.
Participants were divided into normal weight and OW/OB groups according to body mass index. Clinic and 24 h ambulatory
systolic and diastolic blood pressure were measured. Inflammatory markers included leptin, interleukin-6, interleukin-8,
tumour necrosis factor-α, adiponectin, interleukin-10, and C-reactive protein. After adjustments for age, sex, and ethnicity,
the OW/OB group had higher blood pressure and an overall worse inflammatory profile compared to the normal weight
group (all p ≤ 0.024). In the OW/OB group, 24 h systolic (r = 0.22; p < 0.001) and diastolic blood pressure (r = 0.28;
p < 0.001) correlated with leptin, independent of age, sex, and ethnicity. In fully adjusted regression models, 24 h systolic
blood pressure (adj.R2 = 0.25; β = 0.28; p = 0.035) and diastolic blood pressure (adj.R2 = 0.10; β = 0.32; p = 0.034),
associated with leptin in the OW/OB group and significance remained with additional adjustments for visceral adiposity
index. Twenty-four-hour ambulatory, but not clinic blood pressure, is related to leptin in young adults with OW/OB. Leptin
shows a stronger relationship with adiposity when compared to other inflammatory markers and may play a role in
subcutaneous adiposity-related increased blood pressure
Bibliometric Analysis of Data Analytics Techniques in Cloud Computing Resources Allocation
No full textCloud computing provides on-demand computing services over the Internet, allowing for
quicker innovation, more flexible resources, and economies of scale while reducing the
need for physical data centers and servers. With this benefit, most organizations are
adopting this technology, and some organizations are also operating fully on cloud
computing. This causes traffic to increase, and most of these organizations are struggling
with resource allocation, resulting in complaints from users regarding inactive system
performance, timeouts in applications, and higher bandwidth use during peak hours. In
this regard, this study investigates data analytics techniques and tools for the allocation of
resources in cloud computing. The study indexed journal articles from the Scopus
Database and Web of Science (WOS) between 2010 and 2024. This article brings new
insights into the analysis of data analytics techniques in Africa and collaborations with
other developing countries. The findings present tools and approaches that may be used
to allocate cloud computing resources and give recommendations
PERCEPTIONS OF USING E-LEARNING APPLICATIONS IN ACCOUNTING AT RESIDENTIAL UNIVERSITIES IN SOUTH AFRICA: A SOCIAL JUSTICE LENS
Get PDFArticle, Faculty of Economic and Management Sciences (Workwell: Research Unit for Economic; Management Sciences)--Northwest University, Potchefstroom CampusIn a post-COVID world, higher education institutions are debating several divergent delivery modes, searching for the optimal approach, with many calling for change and embracing technology in the current space. However, institutions (and their students) may only be somewhat ready for e-learning, especially in developing economies such as South Africa, with its many social justice challenges. The COVID-19 period forced higher education into the e-learning space, and many students were left behind due to a lack of access, inequity, challenges related to diversity, and the inability to participate in learning. This study aimed to analyse students’ perceptions and experiences with using e-learning applications through the lens of social justice. Qualitative data were collected from accounting students registered at four South African residential universities (n = 1864). Themes emerged from the data analysis performed using a qualitative research analysis tool. These themes were classified and discussed under four social justice principles. The findings indicate a clear link between student experiences of e-learning and social justice, with some students finding successful participation in e-learning significantly more challenging than others. The nature of these challenges should be informative for institutions that are considering moving learning to online modes. Higher education curriculum developers, policymakers, institutions, and academics are encouraged to consider social justice principles when considering adapting to online or blended learning
Nutritional status of Tswana sheep: evaluation of feeding practices and prospects of utilizing protein sources to improve performance
No full textDoctor of Philosophy in Agriculture in Animal Science, North-West University, MafikengThis study was conducted 1) to identify the main feed resources and feeding methods used by small-holder sheep farmers; 2) to determine the nutritional and health status of sheep grazing in communal rangelands and 3) to determine the best cost effective protein source to use for market lambs as a replacement for soybean meal (SBM). The study evaluated the nutrient intake, digestibility, utilization, blood metabolites, performance, carcass traits and meat quality of Tswana lambs fed cereal stover-based diets containing increasing levels of canola meal (CM) and sunflower seed cake (SSC). It was postulated that the growth rate, reproduction performance and immunity level of communal sheep were significantly affected by insufficient nutrient supply from the rangelands. To investigate this, an analysis of herbaceous biomass yield and quality as well as the nutritional status of grazing sheep was conducted across all four (4) districts in Southern and Gaborone agricultural regions of Botswana. Additionally, it was presumed that higher levels of CM or SSC could have a negative impact on feed utilization, growth performance, carcass yield and quality as well as the overall health status of Tswana sheep lambs.
It was determined that feed supply and quality in the investigated communal rangelands were inadequate to sustain sheep production during dry seasons and this might have been exacerbated by their high bush encroachment (canopy cover at 70.63%). Most of small holder farmers utilized crop residues (67%) and lucerne/lablab hays (51%) in feeding their sheep and very few supplement their animals with oilseed meals. This study also evaluated the herbaceous yield and nutritional status of communal rangelands and found that the South East and Southern districts had significantly (P<0.05) lowest and highest feed supply respectively. Hence, sheep in the South East district had the statistically lowest live body weights and BCS in this work and may reflect their low total nutrients intake. Furthermore, the assessment of blood metabolites of sheep in the South East district indicated intense mobilization of protein and energy reserves, probably due to extended feed scarcity and inadequate nutrients consumption during the dry seasons. Sheep from the South East district revealed highest (P<0.05) values of creatinine, BUN, glucose and cholesterol and these are mostly associated with severe hypoproteinamia and hypoglycaemia conditions.
Again, the current study revealed that the nutritional and health status of grazing sheep was affected by their physiological status, with poor (P0.05) crude protein digestibility. The results also showed that diets significantly (P0.05) their final body weights, feed intakes, FCR and BCS. Even though CM and SCC influenced all investigated parameters similarly (P>0.05), CM produced numerically higher values of growth performance in Tswana sheep lambs. Regarding nitrogen utilization, it was found that diets affected (P<0.05) N-intake, weights of excreta (feces and urine) and daily output of fecal nitrogen while daily weights of urine nitrogen, nitrogen balance and retention were not affected. N-intake followed the pattern for total feed intake, DMI and CPI where it was higher (P<0.05) in sheep weaners fed diet SSC75 when compared to those fed diets SSC25 and SCC50 (32.25 vs 28.99 and 28.14 g/ day). Also, fecal output was inversely related to ADF, DMD and OMD levels of the investigated diets and it was significantly higher for sheep fed diets with high inclusions of CM, CM75 (1.02 kg) and CM100 (0.98 kg). Furthermore, all diets resulted in similar concentration levels of blood metabolites (except urea), normal levels of creatinine, total protein, Ca (except SSC100) and P and below normal levels of urea and albumin in Tswana lambs.
Once more, it was observed that all the diets had a significant influence (P<0.05) on various parameters including hot carcass weight (HCW), cold carcass mass (CCM), percentage of meat shrinkage, bone percentage, as well as the weights of ribeye, neck, rib-chop, leg, chump, loin, and rib-flank of the lambs. Animals fed control diet had significantly higher values of HCW and CDM than those that were fed diets SSC25 and SSC100. Furthermore, all CM and SSC diets, except
SSC25, produced non-significant weights of rib-chop, leg, chump, loin and rib-cuts to control diet. The current findings also revealed that substituting SBM with CM or SSC affected the levels of drip loss, cooking loss and tenderness. Lamb meat with the highest drip loss percentage and lowest values of tenderness and highest fat and lowest moisture contents was produced by control and CM100 and SSC100 and SSC75 diets, respectively. Sensory evaluation scores indicated that replacing SBM with CM or SSC significantly affected all investigated sensory attributes of meat except taste and flavour, with higher (P<0.05) scores on tenderness, juiciness and overall impression in meat of lambs fed diet SCC75 than that of lambs fed control diet. From the results, it is concluded that CM or SSC has potential to partially or wholly replace SBM in grower sheep diets and feeding indigenous sheep improved cereal crop residues-based diets with CM or SCC has high chances of increasing mutton meat supply and consumption in hot and dry climates of Africa. A situation of high availability and affordability of animal protein has a high potential of reducing prevalence of undernourishment in the continent
Passive autocatalytic recombination of hydrogen on a Pt/Al2O3-coated metal foam: Experimental evaluation and CFD modelling.
Get PDFJournal Article. Centre of Excellence in Carbon-based Fuels, School of Chemical and Minerals Engineering, Faculty of Engineering, North-West University,
PotchefstroomPt/Al2O3-coated Al foams were tested for the passive autocatalytic recombination of H2. The characterisation of the washcoat surface confirmed the uniform distribution of Pt and Al2O3 over the entire washcoat surface. Transmission electron microscopy results revealed a slight increase in particle size from 3.8 to 6.2 nm after prolonged reaction. High H2 conversions of 57–89% are achieved and the catalyst activity is maintained for >480 h on stream. The performance of the foam-based catalyst bed is similar to that of plates but surpasses that of catalyst pellets. Temperatures recorded at the hottest spots on the foam surface reach a maximum of only 393 °C at the highest H2 inflow. Computational fluid dynamics simulations were performed on the actual foam geometry obtained using computed tomography. The simulations demonstrate the importance of thermal radiation in the model. There is good agreement between results of experimental H2 conversions and maximum combustion temperatures
Nonlinear periodic ion-acoustic waves in nonthermal plasmas
Get PDFJournal Article Pure and Applied Analytics, School of Mathematical and Statistical Sciences, North-West University, Mahikeng CampusA Sagdeev pseudopotential analysis is developed for the propagation of nonlinear periodic ion-acoustic waves in a plasma comprising cold fluid ions and various models of nonthermal electron descriptions. In plasma nonlinear wave studies, whether addressing solitary or periodic modes, the more common nonthermal distributions are the Cairns, kappa, and Tsallis models. A mathematically and physically consistent description incorporates three evident properties: there is conservation per cycle of ion and electron densities in addition to ion flux, the solutions reduce for very small amplitudes to linear waves, and the nonlinear periodic structures are generated by a perturbation of the undisturbed equilibrium. After establishing the corresponding general analytical methodology, a numerical analysis is given, with illustrative graphs, for the nonthermal Cairns, superthermal kappa, and nonextensive Tsallis distributions
Sustainability of Select Indigenous-Language Newspapers Through Advertising in Nigeria: Appraising the Success of Alaroye and Aminiya Newspapers
No full textJournal Article, Faculty of Humanities (Languages) -- North-West University, Mahikeng CampusThis study investigated the sustainability of select Indigenous language newspapers through advertising, emphasising the success stories of Alaroye and Aminiya nespapers. No prior study has examined the success stories of these Indigenous-language newspapers and their sustainability through advertising. Previous studies focused mainly on examining the challenges faced by these papers but paid no attention to the successes of a few of them, thus the need for a study of this nature. The study, therefore assess the advertising techniques used in Indigenous language newspapers to promote sustainability. Specifically, it sought to identify the advertising techniques used to promote sustainability, determine their effectiveness, and identify the challenges Indigenous-language newspapers face in promoting sustainability. A qualitative research method was used for this study. In-depth interviews were held with the advertising managers/representatives of the respective newspapers. Findings show that the newspapers employed various advertising techniques such as print, digital and social media advertising; various advertising choices are available in the newspapers, including display advertisements, classifieds, inserts, and sponsored content. They also promote people’s cultural heritage through published advertising messages. Further findings showed that Alaroye and Aminiya newspapers enhance their sustainability by effectively targeting their desired readers and showing how much they care about preserving culture. The study recommends that Indigenous-language newspapers should emphasise unique cultural perspectives because they can provide a cultural perspective that mainstream media may not offer. By emphasising this cultural perspective, Indigenous-language newspapers can differentiate themselves from other media
outlets and attract advertisers who want to appeal to this unique audience.Partnerships for the Goal
Discover the authenticity of your liberation cultural heritage experience: A market segmentation approach
No full textJournal Article, Faculty of Economic and Management Sciences, Tourism Research In Economic Environs and Society (TREES)-- Potchefstroom CampusThis research addresses a significant gap in the literature concerning the authenticity of tourism experiences, particularly in the context of cultural heritage sites. It focuses specifically on visitors to Liberation Cultural Heritage Sites in South Africa, enriching the discourse on authenticity within cultural heritage tourism. The primary aim was to identify distinct visitor segments at these sites, employing multiple segmentation bases. These bases included socio-demographic variables, visitation behaviour, motivation, and indicators of perceived authenticity, encompassing both object-based and existential aspects and evaluating supporting facilities and services. The study utilises a quantitative methodology, employing a digitally administered survey to gather data. A two-step cluster analysis identified two primary visitor segments: ‘Comprehensive authenticity seekers’ and ‘Emerging authenticity seekers’, with the former constituting
the larger segment. This segmentation is pivotal for cultural heritage site managers, marketers, and policymakers, as it enables the development of tailored strategies that cater to each visitor group’s specific needs and preferences. This research provides valuable insights for optimising resource allocation and enhancing the visitor experience. Such insights are crucial for promoting sustainable growth and competitiveness in cultural heritage tourism.Acknowledgements
This work is based on the research supported by the National Research Foundation (NRF). This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors. The authors are grateful to all the respondents willing to form part of the research. The authors would like to extend their gratitude to Dr. Marco Scholtz for his valuable contributions in the early phases of this research. Any opinion, findings and conclusion or recommendation expressed in this material is that of the authors, and the NRF does not accept any liability in this regard
Two new species and new host and distribution records of Gnathia Leach, 1814 (Crustacea, Isopoda, Gnathiidae) from Western Australia and the Great Barrier Reef, Australia
Get PDFArticle, Faculty of Natural and Agricultural Sciences (Unit for Environmental Sciences and Management)--Northwest University, Potchefstroom CampusGnathia antennacrassa sp. nov. from seagrass beds off Rottnest Island, Western Australia is the first record of any gnathiid from the entirety of Western Australia; the male can be distinguished from congeners by the stout peduncular articles of the antenna. Gnathia taurus sp. nov. is described from two adult specimens reared from praniza larvae found infecting elasmobranch fishes at Heron Island, southern Great Barrier Reef; the males can be distinguished from all congeners by the dorsally strongly elongate mandibles and smoothly rounded mediofrontal process on the anterior part of cephalosome. Gnathia aff. maculosa Ota & Hirose, 2009 is recorded from Australia, together with further records of G. trimaculata Coetzee, Smit, Grutter & Davies, 2009 and G. grandilaris Coetzee, Smit, Grutter & Davies, 2008, all from elasmobranch fishes