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- Nanotechnology addresses numerous environmental problems such as wastewater treatment. Ground water, surface water and wastewater that is contaminated by toxic organic, inorganic solutes and pathogenic microorganisms can now be treated through the application of nanotechnology. The study reports iron@copper (Fe@Cu) nanoparticles, iron nanoparticles (FeNPs) and copper nanoparticles (CuNPs) synthesized using a bioflocculant in a green approach technique. Characterization of the as-synthesized materials was achieved using analytical techniques such as Fourier transform-Infrared spectroscopy (FT-IR), Thermogravimetric analysis (TGA), Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), UV-Vis spectroscopy (UV-Vis) and X-ray diffraction (XRD). The presence of hydroxyl (–OH) and amine (–NH2) groups was shown by FT-IR spectroscopy studies and the as-synthesized material was shown to be thermostable. Elements such as oxygen, carbon, iron and copper were found to be abundant in Wt%. Absorption peaks were found between 200 and 390 nm wavelength and diffraction peaks at 2θ –29°, 33° and 35° for FeNPs, CuNPs and Fe@Cu, respectively. In their application, the effect of various parameters on the flocculation activity were evaluated. Both the CuNPs and (Fe@Cu) nanoparticles have shown the best flocculation activity at a concentration of 0.2 mg/mL with over 90% activity, while the dosage size with a concentration of 0.4 mg/mL was optimal for FeNPs. The FeNPs were found to be cation dependent, while CuNPs and Fe@Cu nanoparticles flocculate in the absence of a cation and flocculate both in acidic and alkaline pH. All the synthesized nanoparticles are thermostable and maintain flocculation activity above 80% at 100 °C. Both the Fe@Cu and CuNPs were found to be effective in removing dyes with the removal efficiency above 89% and were found to be effective in removal of chemical oxygen demand (COD) and biochemical oxygen demand (BOD) in Mzingazi river water and coal mine wastewater with over 80% removal efficiency. Moreover, the synthesized nanoparticles showed some remarkable antimicrobial properties when evaluated against Gram-positive and Gram-negative bacteria. The as-synthesized material was found to be safe to use at low concentration when verified against human embryonic cells (HEK293) and breast cancer cells (MCF7) and biodegradable.
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- An analysis of the use of demonstratives in isiZulu (izabizwana zokukhomba) has shown that they go beyond the known deictic functions of demonstratives as used in other languages like English. In isiZulu, demonstratives tend to also denote specificity, a function normally performed by the definite article in English. This article, therefore, compares the functions of articles in English to those of demonstratives in isiZulu, with the aim to demonstrate the similarities in terms of use between the two languages. This added function of demonstratives, it is argued, may account for some of the errors in English second language learners’ use of articles, as evidenced by data from written exercises of learners whose first language isisiZulu. The findings suggest that second language learners of English tend to confuse articles because of the differences between the two languages, especially during their(learners’) interlanguage stage. Contribution: The article highlights a significant difference in the use of demonstratives between English and isiZulu due to the added function of specificity in isiZulu demonstrative (isabizwana sokukhomba) which is performed by the definite article in English. It also demonstrates how, without an article system, isiZulu can convey meaning like any language with an article system.
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- The current study aims at investigating a modified theory of gravity called theory. Our focus is on a Gauss-Bonnet cosmological model that integrates a non-linear Gauss-Bonnet term and a linear trace term. We assume , where , and represent free parameters. To solve the field equations, we employ a specialized formulation of the deceleration parameter, represented as , where and are model parameters. Consequently, we determine the optimal values of the model parameters by aligning them with the latest observational datasets, including 57 data points from the Cosmic Chronometers datasets, Pantheon datasets, and BAO datasets. Furthermore, we analyze the physical behavior of the cosmographic parameters corresponding to the constrained values of the model parameters, as well as energy density and pressure. The evolution of the deceleration parameter predicts a transition from the decelerated to the accelerated phases of the universe. Importantly, our cosmological model effectively describes the observed cosmic acceleration in the late-time universe, eliminating the need to introduce an additional dark energy component in the field equations.
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- The past few years have seen a rise in both the number and proportion of incarcerated women in South Africa. Even though the rate of incarceration for women continues to be far lower than for men, the number of women in correctional facilities is growing. Hence the aim of this paper is to critically analyze the living conditions of female offenders who are incarcerated in South African correctional centers. This critical analysis was done by means of qualitative document analysis. This paper traverses, synthesizes, and analyses empirical studies as well as other relevant academic and policy literature on women’s incarceration in South Africa to suggest viable strategies and solutions that can be adopted to ensure good practices and address the identified challenges that are associated with the incarceration of women. Furthermore, the paper highlights various adversities that women in correctional facilities face, such as health issues and rehabilitation challenges, as well as the impact that development and care programmes have on them.
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- A critical question to be asked in the modern world is whether or not women should have leadership roles in churches. Saint Paul teaches us that we should have a vision of a church that is unified and which embraces diversity. When he discusses the various gifts of grace within the church in Ephesians (4:11), he is by no means suggesting that the roles of the gifted are linked to gender. It is however also clear from the holy scriptures that no woman was selected to be an apostle. Nonetheless, the Eastern Orthodox Church recognizes that there were a number of woman who were equal in status to the apostles, inter-alia, Saint Helena and Saint Mary Magdalene. In the Graeco-Roman world of New Testament Palestine, religion operated in a highly paternalistic and patriarchal society in which there was often much debate on issues of sexuality and the belief that women per se were not suitable to serve in ecclesial roles was commonplace. When it came to widows however, they enjoyed somewhat of a special status and were able to serve in a particular manner which was deemed to be acceptable. The widows in the early Church provide a thought-provoking Christian character, which springs from their innate desire to do good deeds and from their austere practices that point to solid Christian discipleship even though they functioned honorifically. This article investigates what the Didascalia Apostolorum has to say concerning the status and function of widows in early church life. The Order of Widows which existed in the early Church decayed in importance at the advent of the fourth century, as numerous of its functions were adopted by deaconesses. If we accept that human beings have natures which are created in the imageo Dei, then women are invariably equal in their humanity to men. Why is it then that they are precluded from serving as priests or other ecclesial orders in various denominations? A historical-critical methodology was employed in this brief study making use of literature emanating from academic journals, theological books, early church documents and a range of online sources. This article hopefully enables the reader to develop a great understanding of early Christian widows as consecrated women, serving the Church and God.
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- Despite adapting to the lockdown necessitated by the coronavirus pandemic, higher education institutions in South Africa have acknowledged that continued lockdown further jeopardizes the 2020 academic calendar. This paper looks at what the higher education response has been to continue with academic activity at the onset of Lockdown Level 5. The use of electronic tuition through various media channels has been highlighted since the announcement of lockdown at all levels of education. While this approach may constitute work-in-progress, it also poses many challenges, chief of which is the high cost of Internet access and data. In this paper, an analytical literature review was conducted using communication media analysis through desktop research. Two conceptual structures, the Technology Acceptance Model (TAM) and the Two-way Communication Model (TCM), underpin the study. The paper found that the coronavirus pandemic and lockdown have forced HEIs to rethink their teaching and learning strategy on the run; that online learning has begun but with varying degrees of success; and that implementation presents challenges. Further monitoring post lockdown, to establish the effectiveness of the HEI response, is vital.
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- Considering the global health threat posed by kidney disease burden, a search for new nephroprotective drugs from our local flora could prove a powerful strategy to respond to this health threat. In this study we investigated the antihyperuricemic and nephroprotective potential of RA-3, a plant-derived lanosteryl triterpene. The antihyperuricemic and nephroprotective effect of RA-3 was investigated using the adenine and gentamicin induced hyperuricemic and nephrotoxicity rat model. Following the induction of hyperuricemia and nephrotoxicity, the experimental model rats (Sprague Dawley) were orally administered with RA-3 at 50 and 100 mg/kg body weight, respectively, daily for 14 days. Treatment of the experimental rats with RA-3, especially at 100 mg/kg, effectively lowered the serum renal dysfunction (blood urea nitrogen and creatinine) and hyperuricemic (uric acid and xanthine oxidase) biomarkers. These were accompanied by increased antioxidant status with decrease in malondialdehyde content. A much improved histomorphological structure of the kidney tissues was also observed in the triterpene treated groups when compared to the model control group. It is evident that RA-3 possesses the antihyperuricemic and nephroprotective properties, which could be vital for prevention and amelioration of kidney disease.
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- Malaria is a mosquito-borne disease spread by an infected vector (infected female Anopheles mosquito) or through transfusion of plasmodium-infected blood to susceptible individuals. The disease burden has resulted in high global mortality, particularly among children under the age of five. Many intervention responses have been implemented to control malaria disease transmission, including blood screening, Long-Lasting Insecticide Bed Nets (LLIN), treatment with an anti-malaria drug, spraying chemicals/pesticides on mosquito breeding sites, and indoor residual spray, among others. As a result, the SIR (Susceptible—Infected—Recovered) model was developed to study the impact of various malaria control and mitigation strategies. The associated basic reproduction number and stability theory is used to investigate the stability analysis of the model equilibrium points. By constructing an appropriate Lyapunov function, the global stability of the malaria-free equilibrium is investigated. By determining the direction of bifurcation, the implicit function theorem is used to investigate the stability of the model endemic equilibrium. The model is fitted to malaria data from Benue State, Nigeria, using R and MATLAB. Estimates of parameters were made. Following that, an optimal control model is developed and analyzed using Pontryaging's Maximum Principle. The malaria-free equilibrium point is locally and globally stable if the basic reproduction number (R0) and the blood transfusion reproduction number (Rα) are both less or equal to unity. The study of the sensitive parameters of the model revealed that the transmission rate of malaria from mosquito-to-human (βmh), transmission rate from humans-to-mosquito (βhm), blood transfusion reproduction number (Rα) and recruitment rate of mosquitoes (bm) are all sensitive parameters capable of increasing the basic reproduction number (R0) thereby increasing the risk in spreading malaria disease. The result of the optimal control shows that five possible controls are effective in reducing the transmission of malaria. The study recommended the combination of five controls, followed by the combination of four and three controls is effective in mitigating malaria transmission. The result of the optimal simulation also revealed that for communities or areas where resources are scarce, the combination of Long Lasting Insecticide Treated Bednets (u2), Treatment (u3), and Indoor insecticide spray (u5) is recommended. Numerical simulations are performed to validate the model's analytical results.
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- 2022| AIMS PressWe propose a theoretical model which helps us to use entangled graphene sheets for inducing T-cells around tumor cells. The direction of the free spinors on a graphene sheet should be in the opposite direction to the direction of the free spinors on the other graphene sheet in an entangled system. Consequently, any change in one sheet could be understood by spinors in the other sheet. One of these graphene sheets plays the role of antenna within the human body, and the other one acts as the sender exterior to it. With time and the motion of the total wave, the graphene sheet divides into smaller components with lower energy on some circles, and the centre of such a circle is the sender. Thus, to provide the required energy for activation of the interior graphene sheet, we add more sheets or increase the external potential exterior to the body. According to the Warburg proposal, radiated spinors from normal cells and cancer cells are different, and these differences could be seen by free spinors on the exterior of the graphene sheets. When the existence of a tumor is diagnosed, some T-cells could be close to the exterior graphene sheets. Free spinors on these sheets change, take the shape of T-cells and transmit information to the interior sheet. Spinors on this sheet produce virtual T-cells which deceive the tumor cells and produce virtual PD1/PD-L1 connections with them. Consequently, tumor cells cannot introduce death toxins into real T-cells, and these cells have the opportunity to destroy them.
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- 2022| AIMS PressIt is known that differences between potentials of soma, dendrites and different parts of neural structures may be the origin of electroencephalogram (EEG) waves. These potentials may be produced by some excitatory synapses and currents of charges between neurons and then thereafter may themselves cause the emergence of new synapses and electrical currents. These currents within and between neurons emit some electromagnetic waves which could be absorbed by electrodes on the scalp, and form topographic images. In this research, a model is proposed which formulates EEG topographic parameters in terms of the charge and mass of exchanged particles within neurons, those which move between neurons, the number of neurons and the length of neurons and synapses. In this model, by knowing the densities of the frequencies in different regions of the brain, one can predict the type, charge and velocity of particles which are moving along neurons or are exchanged between neurons.
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- 2022| AIMS PressPrevious experiments have shown that extremely low frequency electromagnetic fields could cause serious effects on the evolution of cells. We propose a mathematical model which confirms those results. In our model, electromagnetic waves could cause the motions of ions and charges and the emergence of some currents around and in the interior of cells. These currents produce some waves which interact with the DNAs and remove or attach some repressors. Consequently, some genes could be turned on or off, and cells could obtain some properties or lose them. The frequency of the external waves should be close to the frequency of the exchanged waves between the repressors and DNAs or even bigger than them. We test this idea and did some experiments on quail embryonic cells. We connected a sample of these cells to a battery and considered their evolution. We observed that after connecting the battery and the production of electrical current, some rings around the quail embryonic cells emerged. Maybe, these rings are the response of the cells to changes in electromagnetic waves and electrical currents.
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- We investigate a bounce realization in the framework of higher order curvature in f (R, T ) modified theory of gravity. We perform a detailed analysis of the cosmological parameters to explain the contraction phase, the bounce phase, and the expansion phase. Furthermore, we observe a violation of the null energy condition, instability of the model, and a singularity upon deceleration at the bouncing point, which are the supporting results for a bouncing cosmology. The equation of state parameter exhibits a ghost condensate behavior of the model near the bouncing point. Additionally, we discuss the stability of the model using linear perturbations in the Hubble parameter as well as the energy density.
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- This study optimised a novel autoclave-assisted Fe3O4 nanoparticle pre-treatment (NAAP) for the improvement of reducing sugar (RS) recovery from potato peel waste. The optimised NAAP was further assessed for other lignocellulosic substrates, recyclability, animal feed and bioethanol production. Maximum RS yield of 0.324 g/g was obtained with the optimised NAAP conditions. Recyclability resulted in an average RS yield of 0.254 g/g over three pre-treatment cycles. Moreover, the optimised NAAP for the pre-treatment of corn cob (0.021 g/g), cassava peels (0.242 g/g), bamboo stem (0.357 g/g), Amaranthus (0.428 g/g), sorghum leaves (0.867) and banana pseudostem (1.392 g/g) demonstrated its versatility. Furthermore, the potential of the optimised pre-treated biomass for animal feed waste valorisation and bioethanol production (22.82 g/L) was achieved. The present NAAP pre-treatment provides novel insights on the application of nanotechnology in lignocellulosic bioprocessing, which could eliminate chemical and enzyme usage, while reducing the process costs and its associated negative environmental impact.
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- In this study we propose a model for building a holographic ultrasound microscope. In this model two mobile phones are f irst connected by waves and techniques like the WhatsApp waves. If the mobile phones are close to each other, their inductors and speakers become entangled, they exchange electromagnetic and sound waves, and they vibrate many times with each other. Objects placed between two mobile phones change the sound waves and electromagnetic waves and appear as holographic images within the inductors and also on the plastic of the speakers. To see these images, a hologram machine is built from a room of plastic, one or two magnets, iron particles, and sound producers. Holographic waves change the magnetic field within the hologram machine and move the plastic and iron particles. These objects take the shape of waves and produce holographic images. To see microbes, one can send a weak current to a container of microbes and then connect it to an amplifier. The weak current takes the shape of the microbes and is amplified by one strong amplifier. Then this current goes to the mobile phone and sound card and, after passing some stages, is sent to the second mobile phone. In the second mobile phone, the sound wave is amplified by speakers and transmitted to the hologram machine. Consequently, particles within this machine move and produce big holographic images of the microbes.
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- Listeria monocytogenes is a zoonotic food-borne pathogen that is associated with serious public health and economic implications. In animals, L. monocytogenes can be associated with clinical listeriosis, which is characterised by symptoms such as abortion, encephalitis and septicaemia. In human beings, listeriosis symptoms include encephalitis, septicaemia and meningitis. In addition, listeriosis may cause gastroenteric symptoms in human beings and still births or spontaneous abortions in pregnant women. In the last few years, a number of reported outbreaks and sporadic cases associated with consumption of contaminated meat and meat products with L. monocytogenes have increased in developing countries. A variety of virulence factors play a role in the pathogenicity of L. monocytogenes. This zoonotic pathogen can be diagnosed using both classical microbiological techniques and molecular-based methods. There is limited information about L. monocytogenes recovered from meat and meat products in African countries. This review strives to: (1) provide information on prevalence and control measures of L. monocytogenes along the meat value chain, (2) describe the epidemiology of L. monocytogenes (3) provide an overview of different methods for detection and typing of L. monocytogenes for epidemiological, regulatory and trading purposes and (4) discuss the pathogenicity, virulence traits and antimicrobial resistance profiles of L. monocytogenes.
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- Malnutrition is a considerable contributor to child mortality and morbidity. Child malnutrition further affects the country’s economic development. Child malnutrition in South Africa is persistent, continuing to be an alarming burden. The nutritional status of kids under the age of five years is a critical indicator of the country’s economic condition and health status. An understanding of the influencers of the nutritional status of children can act as a catalyst in combatting all forms of malnutrition. The purpose of this paper was to review selected studies concerning the factors that affect the nutritional status of children in South Africa. Studies were selected from electronic databases, which were PubMed, Google Scholar, Science Direct, Sabinet African Journals, and the University of Zululand library catalog. The keywords that were used to search studies and articles from the selected database were: risk factors, child nutritional status, children under the age of five years, South Africa, malnutrition, underweight, stunted, wasting, and over-nutrition. Studies and surveys published from 2010–2019 that reported on the factors influencing the nutritional status of children under the age of five years were included in this review. Twenty-seven articles met the inclusion criteria of the study. The 27 articles were made up of 21 cross-sectional articles and six longitudinal articles. The finding from this review highlights that there is a lack of studies conducted in urban areas. The results show that the nutritional status of children is affected by several factors. These include household food insecurity, low household income, illiterate caregivers, unemployment, inadequate dietary intake, low birth weight, consumption of monotonous diets, poor caregiver’s nutritional knowledge, poor access to water and sanitation, poor weaning practices, age of the caregiver, and demographic characteristics of a child (age and gender). It is critical to have an understanding of the factors that affect the nutritional status of children. Such knowledge can significantly contribute to formulating policies that can enhance nutrition security and the country’s economy. Moreover, insights into strategic interventions to eradicate all forms of malnutrition can be made.
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- Context: Field hockey is a very technical and tactical sport, requiring immense levels of visual concentration on moving and stationary targets, which can improve visual and team performance. However, in literature, this area of specialty remains underutilized, with most studies seeking to improve physical and physiological performance. Essential visual skills cannot only be attributed to field hockey but to other ball-playing sports and activities of daily living, which allow humans to coexist. The essential visual skills reduce the propensity of making poor decisions, ill preparations, and the exclusion of potent and capable players. Objectives: This review novelly aims to not only compile a comprehensive list of essential visual skills for field hockey players but also to create a starting point for future studies to add to this list, to aid in player talent identification, and eventually create sportspecific visual exercise programs and testing batteries. Discussion: The skills identified in this review preface a platform for human performance professionals to include in their training regimens, with an intent to maximize performance and talent identification and to aid in the formulation of visuospatial test batteries. Even though this list is comprehensive, this is only a starting point for future research to find more visual skills that are essential to field hockey, as well as provide the opportunity to develop the performance of the visual skills of these athletes in ways that have not been done before.
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- Background. Many sports place demands on vision and certain visual skills, and this has long been acknowledged. Among all activities, athletic performance places some of the highest demands on the visual system. Sports vision's fundamental component is the growth and improvement of an athlete's visual ability. Objectives. To identify a variety of visual skills essential to netball players. Methods. Studies were obtained from the following databases: EBM Reviews, Current Contents, Science Direct, Google Scholar, CISTI Source (1993–June 2021), SportDiscuss (1975–June 2021), Cochrane Database of Systematic Reviews, PubMed (1966–June 2021), and international e-catalogues. A keyword search yielded MeSH headings;“visual skills,“hand-eye coordination”,“peripheral vision”,“eye movements”,“netball vision”,“netball rules”,“reaction time”,“speed of recognition”,“accommodation facility,”“visual memory”,“discriminating efficiency”,“visual endurance”,“motor learning” and “cognitive function” which were combined and exploded. Results. This study used 65 full-text English-language papers from 90 citations found through electronic searches. 40 Articles remained after removing duplicates and reviewing the full-text versions. Conclusion. The evidence in this study reveals that, although current research still frequently concentrates on visual skills, there is a need to narrow this attention to the requirements of a certain sport. Additionally, identifying the visual abilities necessary for netball, enables talent identification, effective training, and testing of these abilities.
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- 2022| Frontiers MediaIn ball sports such as soccer, the visual system is critical in guiding a player’s search for crucial information that underpins skillful behavior, which requires the incorporation of all of the relevant information in the environment in order to make successful decisions under pressure. However, vision in sport, and focusing on the specific visual skills required to be successful in a particular sport has largely been a practice ignored by experts and coaches as being an essential component of athletic performance. This is the first attempt to summarize and compile the necessary visual skills for soccer. This review’s evidence suggests that, while current research still tends to focus on visual skills as a whole, there is a need to streamline this focus to the necessities of a particular sport. Furthermore, in identifying the visual skills essential for soccer, it allows for the active training and testing of these skills, as well as for talent identification.
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- This study analyses the impact of fiscal policy on the South African economy during the period 1972Q1-2020Q2. The study adopted quarterly time series data to estimate a Bayesian Vector Autoregression (BVAR) model with the selection of hierarchical priors. The variables employed for empirical investigation included GDP, government expenditure, public debt, and gross fixed-capital formation. The results of the study show that an unexpected shock in government expenditure and public debt has a significant negative and persistent impact on economic growth in South Africa, while an unexpected shock in investment has a significant positive effect on economic growth. The findings suggest that escalating public expenditure and public debt lead to economic contraction. This implies that policy-makers ought to be cautious of excessive government expenditure and public debt to achieve fiscal consolidation. Policy-makers ought to focus on addressing structural challenges through the implementation of sound structural reform policies that aim to attract investment consistent with job creation, development and growth in South Africa’s economy.
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