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Nitrogen functionalization of CVD grown three-dimensional graphene foam for Hydrogen evolution reactions in Alkaline media
Get PDFAbstract: Three-dimensional graphene foam (3D-GrFoam) is a highly porous structure and sustained lattice formed by graphene layers with sp2 and sp3 hybridized carbon. In this work, chemical vapor deposition (CVD)—grown 3D-GrFoam was nitrogen-doped and platinum functionalized using hydrothermal treatment with different reducing agents (i.e., urea, hydrazine, ammonia, and dihydrogen hexachloroplatinate (IV) hydrate, respectively). X-ray photoelectron spectroscopy (XPS) survey showed that the most electrochemically active nitrogen-doped sample (GrFoam3N) contained 1.8 at % of N, and it exhibited a 172 mV dec−1 Tafel plot associated with the Volmer– Heyrovsky hydrogen evolution (HER) mechanism in 0.1 M KOH. By the hydrothermal process, 0.2 at % of platinum was anchored to the graphene foam surface, and the resultant sample of GrFoamPt yielded a value of 80 mV dec−1 Tafel associated with the Volmer–Tafel HER mechanism. Furthermore, Raman and infrared spectroscopy analysis, as well as scanning electron microscopy (SEM) were carried out to understand the structure of the samples
Covid-19 and local business responses : evidence from South Africa’s most tourism-dependent locality
Get PDFAbstract: In emerging tourism scholarship around COVID-19 one of the major clusters of research surrounds issues of adaptation. Tourism businesses are compelled to adapt to shifts in consumer demand as well as government regulatory changes. The objective in this paper is to investigate the responses and adaptations to the impacts of COVID-19 of tourism businesses in South Africa’s most tourism-dependent locality. The research reports on 20 qualitative interviews undertaken with a cross-section of tourism enterprises in Bela-Bela Local Municipality, Limpopo province, which is overwhelmingly oriented towards the market of domestic tourism. Major results are local businesses are financially negatively impacted by the subdued nature of domestic leisure travel together with the near total collapse of business travel as well as the imperative to conform to new COVID-19 safety and health protocols. Adaptive responses have included downsizing of businesses, including worker retrenchments, price-cutting, limited initiatives towards product diversification, energetic social media marketing and repurposing of properties. Key challenges for Bela-Bela tourism enterprises relate to immediate financial issues and most especially in the context that minimal support has been provided by national government to assist their business survival. Future business prospects are not viewed favourably such that business closures and a hollowing out of the tourism enterprise base accompanying job losses in tourism appear inevitable
Human capital and economic growth in South Africa : a cross-municipality panel-data analysis
Get PDFAbstract: Background: In the literature, human capital has been identified as a key economic variable that isneeded to promote growth; hence this study explores the components of human capital, that is,different skill levels in order to capture the real effect of the employed labour on economic outputacross the municipalities of South Africa. Aim: This study investigates the effect of human capital of employed labour on economic output andgrowth in South Africa. Setting: The study focusses on the balanced panel of 269 South African municipalities for the period 1993to 2016. Method: The study utilises panel causality test and the Generalised Method of Moments (GMM) estimationtechniques. Results: A panel causality test confirms bidirectional causality between human capital and total output aswell as between total employment and total output. The resultant aggregate findings suggest that humancapital has a positive and a significant impact both on total output and economic growth. The disaggregatedproxy of human capital shows that higher levels of skilled employment is associate with higher total outputand economic growth. Conclusion: The findings on the effect of skilled employment on economic growth are in line withtheoretical literature and therefore the study concludes that human capital in the form of skilled labour has apositive effect on both economic output and growth in South Africa. This informs policy to prioritise the up-skilling of the labour force in order to contribute positively towards value generating economic activities in South Africa
Chimeric Antigen Receptor (CAR) T cell therapy for metastatic melanoma : challenges and road ahead
Get PDFAbstract: Metastatic melanoma is the most aggressive and difficult to treat type of skin cancer, with a survival rate of less than 10%. Metastatic melanoma has conventionally been considered very difficult to treat; however, recent progress in understanding the cellular and molecular mechanisms involved in the tumorigenesis, metastasis and immune escape have led to the introduction of new therapies. These include targeted molecular therapy and novel immune-based approaches such as immune checkpoint blockade (ICB), tumor-infiltrating lymphocytes (TILs), and genetically engineered Tlymphocytes such as chimeric antigen receptor (CAR) T cells. Among these, CAR T cell therapy has recently made promising strides towards the treatment of advanced hematological and solid cancers. Although CAR T cell therapy might offer new hope for melanoma patients, it is not without its shortcomings, which include off-target toxicity, and the emergence of resistance to therapy (e.g., due to antigen loss), leading to eventual relapse. The present review will not only describe the basic steps of melanoma metastasis, but also discuss how CAR T cells could treat metastatic melanoma. We will outline specific strategies including combination approaches that could be used to overcome some limitations of CAR T cell therapy for metastatic melanoma
The effects of COVID-19 on international students in South Africa
Get PDFAbstract: The outbreak of COVID-19 pandemic has put the entire world in a state of abrupt confusion and panic. This has affected different sectors in various walks of life: inclusive of education. People tend to continuously live in fear while seeking support from their governments. Conversely, governments and institutions of learning attempt to combat the pandemic by employing different strategies in order to help their citizens, however, foreign nationals in different countries seem to be left-out. Hence, this paper was targeted at examining the lived experiences of international students in developing nations during the COVID-19 pandemic. A review method was adopted for the study. Hence, relevant literature was reviewed. The findings of the study show that developing nations like the world have been badly hit by the outbreak of COVID-19 pandemic, and the effect tends to be more severe for international students as focus was more on the citizens than foreign nationals. Also, the increasing rate of the pandemic affected the operation of higher education institutions through the imposed closure of university residences which exposed many international students to undue hardship. The study therefore recommends that there is an urgent need for the institutions of higher learning in developing nations to rethink their policy on internalisation towards a better welfare structure for international students
Examining the interface between bureaucratic conflict and public interest in Africa
Get PDFAbstract: Background: In every human organisation, there is bound to be conflict of ideas because everyone wants his or her viewpoint to take precedent over others. There are those who want to be on top of every situation irrespective of those involved or the issue at stake. However, a proactive bureaucratic leadership should be able to find a way out of these quagmires. Aim: Within the framework of the strategic elite theory, this article examines the nexus between bureaucratic conflict and public interest in Africa, as well as challenges confronting bureaucracy in the pursuit of public interest with specific reference to Nigeria. Method: This article adopts a qualitative approach and is descriptive in nature, with the researcher setting out to illustrate the association that exists between the dependent and independent variables. Authoritative scholarly sources were reviewed during a desktop study. The purpose was to identify the relevant publications and apply them in the research. Results: This article argues that whilst conflict generally is an inevitable outcome of human interactions. However, conflict is more common in a bureaucratic organisation where issues of power and influence are always a source of contention amongst the Ministries, Departments and Agencies (MDAs). Therefore, resolving the basis for the existence of the MDAs that will ultimately inculcate in the bureaucrats a new worldview. Conclusion: It therefore, concludes that there should be countervailing forces to put the bureaucracy on check. This includes: strengthening interest groups, the pursuit of institutionalism, ethical reorientation in the public service, amongst other measures. However, to achieve this, requires a critical mass of men and women of integrity, doggedly and ruggedly committed to Africa’s project and ready to subsume their personal interests under that of the national interests
Facile extraction and characterization of silica nanoparticles from corn stalk by sol-gel hydrothermal methods
Get PDFAbstract: Lightweight aggregates, drug delivery and energy storage are some of the numerous applications of silica nanoparticles. Amorphous silica was extracted from corn stalk using the sol-gel hydrothermal method and nanostructured using Hexadecyl trimethyly ammonium bromide (CTAB) as template. The crystallographic structures of synthesized silica nanoparticles was characterized using X-Ray Diffraction (XRD). Functional groups was determine using fourier transform infrared (FT-IR) techniques, specific surface area was determine using the Brunauer Emmett Teller (BET) method. The presence of SiO2 was confirmed by Energy dispersive X-ray (EDX), surface morphology and particle size was examine using scanning electron microscope (SEM) and transition electron microscope (TEM). This study provide a silica nanoparticles sourced from agricultural biomass for cutting-edge applications including drug delivery
Measurement of the CP-violating phase s in B →J/ decays in ATLAS at 13 TeV
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A methodology for examining geotourism potential at the Kruger National Park, South Africa
Get PDFAbstract: In contrast to Europe, Asia and South America where geotourism is actively pursued, geotourism activities in South Africa have not to-date been a focus of tourism products. The purpose of this paper is to propose a field methodology that can be used to assess the potential for geotourism development. Existing procedures to establish geotourism site potential are reviewed and a new methodology that accounts for more characteristics than currently found in documented methods is proposed. This consists of three phases: creating a standardised manner of inventorying the sites; standardising field rank scoring for each site by geotourism value, cultural value, ecological sensitivity, accessibility, development requirements, currently available academic literature, and, developing a final multi-site database assisting the South African National Parks to preserve geoheritage sites. Based on previous studies, the Kruger National Park has geoheritage sites that could form the basis for geotourism development: therefore, the methodology was piloted in its northern regions at well-known geoheritage sites. The findings of this study intend to assist the South African National Parks, local community leaders, the private sector (including existing tour operators) and government departments in achieving a national database of geoheritage sites to ultimately be associated with sustainable tourism activity led by local communities
Observation of photon-induced +，- production in collisions at √ = 13 TeV using the ATLAS detector
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