Search

Streams of the Passi sub-watershed, a tributary downstream of the Mungo River, are important sources of water for agro-industrial activities, irrigation, drinking and other household activities of the surrounding population. This study was conducted to determine the water quality of the Passi sub-watershed. Seven water samples were collected from different points including the confluence with the Mungo River and analyzed for physicochemical parameters, hydrochemicals and trace metal elements. Descriptive statistical analysis (DSA) and Pearson correlation were performed to show the relationship between samples and access the sources of chemicals in the watershed. pH was acidic and did not fall within the range of the World Health Organization (WHO) limits for drinking water. Fe and PO43- in a single site of Mboma were above the WHO permissible limits of the set quality standards for surface water. Pearson correlation analysis showed a significant positive correlation between Na, Ca, Mg, K, P and Cl indicating a common geogenic origin. DSA and chemical ratios revealed a significant difference in water quality of the Mboma stream which exhibited high concentrations of hydrochemicals and trace metals with respect to the other sampling points, highlighting anthropogenic influence from leaching of fertilizers and discharge of effluent from processing of palm oil. The results of this study point out the need for these stream waters to be managed properly for the benefit of the end-users.

Tide and salinity data collected at minute intervals over multiple semidiurnal tides were used to investigate the source of water (e.g., seawater, river, groundwater and rain) and their relative timing in mixing at the mouth of a river, a tidal creek at mid-estuary and a tidal creek at the shoreline at the head of a tropical mangrove estuary. Our objectives were to document the temporal changes in tide induced water level changes and salinity at each location and to use the relationship between salinity and water level to elucidate the sources of water and the timing of different sources of water in the hydrologic mixing processes. The data trends in tide vs. salinity (T-S) plots for the river mouth revealed mixing with seawater during rising tides and freshwater diluted seawater (brackish) drainage from the mangrove forest during ebb tides. In the mangrove creek at mid-estuary, the data trends in the T-S plots for rising tides initially showed constant salinity, followed by sharp rises in salinity to peak tide caused by seawater intrusion. The salinity decreased precipitously at the start of tidal ebbing due to influx of freshwater (rain) diluted brackish water from the mangrove forest. The data trends in the T-S plots for the tidal creek at the shoreline located at the estuary head showed constant salinity which decreased only near peak rising tide because of river dilution. During tidal ebbing, the salinity further decreased from groundwater influx before increasing to background salinity, which stayed constant to low tide. Establishing T-S patterns for multiple locations in mangrove estuaries over sub-tidal to tidal scales define the expected salinity variations in seawater-freshwater mixing which can be used to (1) establish baseline hydrologic and salinity (hydrochemical) conditions for temporal and spatial assessments and (2) serve to guide short to long-term sampling regimes for scientific studies and estuarine ecosystem management.

While higher education is crucial for the development of ideals and skills necessary for democratic societies to take root and prosper, higher education institutions' missions have been tested during this time of uncertainty. The COVID-19 pandemic has revealed the instabilities and disparities in global higher education by exacerbating profound social fractures and long-standing structural imbalances. As such, the study examined how the COVID-19 pandemic has affected rural higher education institutions in building a sustainable and democratic future. It also examined students and staffs' perspectives on how these higher education institutions responded to the COVID-19 pandemic in building a resilient, inclusive and democratic culture. Informed by an interpretivist paradigm, the study utilised a qualitative research approach and a case study design. Data were collected at two rural universities from university managers, lecturers and students using interviews. The study's findings revealed that while the Covid-19 pandemic represents a time of survival of the fittest, which also strengthened democratic tenets and revolutionised the higher education sector, the pandemic has revealed pre-existing institutional issues and vulnerabilities in rural higher education institutions. Research findings also revealed that the pandemic has also spotlighted the poor and the most vulnerable in society as rural HEIs endeavoured to build resilience, and an inclusive and democratic culture to stay sturdy in the face of the 'new normal' and emerge stronger from the COVID-19 pandemic. Based on the study's findings, it was concluded that building a resilient, inclusive and democratic culture at HEIs could generate success for higher education institutions by influencing students' career opportunities and employment readiness, amongst many others. We recommend that HEIs consider focusing more on equity and inclusion; reinforce capacities for risk management at all levels of the system; strong leadership and coordination; and enhance consultation and communication mechanisms.

Douala is one of the largest cities in sub-Saharan Africa where 80% of the population relies on groundwater without any control of their quality. In this context, this study evaluates the groundwater quality and the implications for human health. Water samples, including hand dugs wells, spring waters and borehole were collected. pH values are out of the WHO limit, with too much acidity for human consumption. Three water types are identified: Na–Cl (76.2%), Ca–Cl (14.3%) and Ca-Mg-Cl (9.5%) indicating significant anthropogenic fingerprint. Water Quality Index shows that 90.5% of the samples have “poor” to “unsuitable” quality for drinking purposes. Heavy metal Pollution Index and Heavy Metal Evaluation Index highlight that the groundwater are “lightly” to “moderately” polluted. Human Health Risk tool shows that heavy metal poses a non-carcinogenic risk by ingestion of water for child. These results highlight the necessity of groundwater monitoring to ensure a sustainable water supply.

A multi-tracer approach has been implemented in the southwestern part of the Lake Chad Basin to depict the functioning of aquifers in terms of recharge, relationship with surface water bodies, flow paths and contamination. The results are of interest for sustainable water management in the region. The multi-layered structure of the regional aquifer was highlighted with shallower and intermediate to deep flow paths. The shallower aquifer is recharged with rainwater and interconnected with surface water. The groundwater chemistry indicates geogenic influences in addition to a strong anthropogenic fingerprint. The intermediate to deep aquifer shows a longer residence time of groundwater, less connection with the surface and no to only a little anthropogenic influence. Ambient Background Levels (ABLs) and Threshold Values (TVs) show the qualitative status of the groundwater bodies and provide helpful information for water resources protection and the implementation of new directives for efficient and more sustainable groundwater exploitation.

While higher education is crucial for the development of ideals and skills necessary for democratic societies to take root and prosper, higher education institutions’ missions have been tested during this time of uncertainty. The Covid-19 pandemic has revealed the instabilities and disparities in global higher education by exacerbating profound social fractures and long-standing structural imbalances. As such, the study examined how the Covid-19 pandemic has affected rural higher education institutions in building a sustainable and democratic future. It also examined students and staffs’ perspectives on how these higher education institutions responded to the Covid-19 pandemic in building a resilient, inclusive and democratic culture. Informed by an interpretivist paradigm, the study utilised a qualitative research approach and a case study design. Data were collected at two rural universities from university managers, lecturers and students using interviews. The study’s findings revealed that while the Covid-19 pandemic represents a time of survival of the fittest, which also strengthened democratic tenets and revolutionised the higher education sector, the pandemic has revealed pre-existing institutional issues and vulnerabilities in rural higher education institutions. Research findings also revealed that the pandemic has also spotlighted the poor and the most vulnerable in society as rural HEIs endeavoured to build resilience, and an inclusive and democratic culture to stay sturdy in the face of the ‘new normal’ and emerge stronger from the Covid-19 pandemic. Based on the study’s findings, it was concluded that building a resilient, inclusive and democratic culture at HEIs could generate success for higher education institutions by influencing students’ career opportunities and employment readiness, amongst many others. We recommend that HEIs consider focusing more on equity and inclusion; reinforce capacities for risk management at all levels of the system; strong leadership and coordination; and enhance consultation and communication mechanisms.

ObjectivesUsing quantitative coronary angiography (QCA), optical coherence tomography (OCT), histomorphometry, and pharmacokinetics, this study tried to evaluate the safety and efficacy of Biomagic rapamycin-eluting bioabsorbable scaffold (BVS) in non-atherosclerotic porcine coronary arteries.BackgroundBiomagic BVS is a new generation of thin-strut bioabsorbable scaffold. We conducted comparative study detailing pathological response, safety and efficacy of Biomagic BVS and the Firebird2 rapamycin-eluting cobalt-based alloy stent (DES) in a porcine coronary artery model. The animals were followed up at 14 days, 1, 3, 6, 12, 18, 24, 30, 36, 42, 48, 54, and 60 months after stent implantation.MethodsA total of 143 devices (95 Biomagic and 48 Firebird2) were implanted in 2 or 3 main coronary arteries of 76 nonatherosclerotic swine and examined by QCA, OCT, light microscopy, and pharmacokinetics analyses at various time points.ResultsVascular responses to Biomagic and Firebird2 were largely comparable at all time points, with struts being sequestered within the neointima. The degree of inflammation of both devices was mild to moderate, although the Biomagic score was higher at 14 days to 24 months. However, there was no statistical difference between the two groups except 14 days. At each follow-up time point, the percentage of area stenosis in the Biomagic group was greater than that in the Firebird 2 group, but there was no statistical difference between the two groups at 3 and 12 months. The extent of fibrin deposition was similar between Biomagic and Firebird2, which peaked at 1 month and decreased rapidly thereafter. Pharmacokinetic study showed that coronary tissue sirolimus concentration remained above 2 ng/mg of tissue at 28 day. Histomorphometry showed expansile remodeling of Biomagic-implanted arteries starting after 12 months, and lumen area was significantly greater in Biomagic than Firebird2 at 36 and 42 months. These changes correlated with dismantling of Biomagic seen after 12 months. OCT images confirmed that degradation of Biomagic was complete by 36 months.ConclusionsBiomagic demonstrates comparable long-term safety to Firebird2 in porcine coronary arteries with mild to moderate inflammation. Although Biomagic was associated with greater percent stenosis relative to Firebird2 within 36 months, expansile remodeling was observed after 12 months in Biomagic with significantly greater lumen area at ≥36 months. Scaffold resorption is considered complete at 36 months.

Abstract Introduction Index-linked HIV testing, targeted at sexual contacts or children of individuals with HIV, may improve yield and efficiency. The B-GAP study evaluated index-linked testing approaches in health facility and community-based settings. This paper reports on a qualitative study to understand factors that affect uptake of index-linked HIV testing for children and adolescents. Methods We conducted four focus group discussions (FGDs) with caregivers who had their children tested through B-GAP and one FGD with providers who offered index-linked HIV testing to indexes. We aimed to understand enabling and inhibiting factors in the decision-making process. Translated and transcribed transcripts were read for familiarisation. Following initial coding, analytical memos were written to identify emerging key themes across the data. Results Our findings showed there was inadequate emphasis on paediatric HIV in routine care which had a negative impact on subsequent uptake of testing for children. Once the decision to test had been made, access to facilities was sometimes challenging and alleviated by community-based testing. A key finding was that HIV testing is not a discrete event but a process that was influenced by relationships with other family members and children themselves. These relationships raised complex issues that could prevent or delay the testing process. Conclusion There is a need to improve messaging on the importance of HIV testing for children and adolescents and to provide support to caregivers and their families in order to improve testing uptake. Addressing access barriers through the provision of community-based testing and implementing a family-centred approach can optimise index-linked testing.

The direct impact and sequelae of infections in children and adults result in significant morbidity and mortality especially when they involve the central (CNS) or peripheral nervous system (PNS). The historical understanding of the pathophysiology has been mostly focused on the direct impact of the various pathogens through neural tissue invasion. However, with the better understanding of neuroimmunology, there is a rapidly growing realization of the contribution of the innate and adaptive host immune responses in the pathogenesis of many CNS and PNS diseases.The balance between the protective and pathologic sequelae of immunity is fragile and can easily be tipped towards harm for the host. The matter of immune privilege and surveillance of the CNS/PNS compartments and the role of the blood-brain barrier (BBB) and blood nerve barrier (BNB) makes this even more complex. Our understanding of the pathogenesis of many post-infectious manifestations of various microbial agents remains elusive, especially in the diverse African setting. Our exploration and better understanding of the neuroimmunology of some of the infectious diseases that we encounter in the continent will go a long way into helping us to improve their management and therefore lessen the burden.Africa is diverse and uniquely poised because of the mix of the classic, well described, autoimmune disease entities and the specifically “tropical” conditions. This review explores the current understanding of some of the para- and post-infectious autoimmune manifestations of CNS and PNS diseases in the African context. We highlight the clinical presentations, diagnosis and treatment of these neurological disorders and underscore the knowledge gaps and perspectives for future research using disease models of conditions that we see in the continent, some of which are not uniquely African and, where relevant, include discussion of the proposed mechanisms underlying pathogen-induced autoimmunity. This review covers the following conditions as models and highlight those in which a relationship with COVID-19 infection has been reported: a) Acute Necrotizing Encephalopathy; b) Measles-associated encephalopathies; c) Human Immunodeficiency Virus (HIV) neuroimmune disorders, and particularly the difficulties associated with classical post-infectious autoimmune disorders such as the Guillain-Barré syndrome in the context of HIV and other infections. Finally, we describe NMDA-R encephalitis, which can be post-HSV encephalitis, summarise other antibody-mediated CNS diseases and describe myasthenia gravis as the classic antibody-mediated disease but with special features in Africa.

Stochastic differential equations (SDEs) are very often used as models for a large number of phenomena in the physical, economic and management sciences. They generalize the notion of ordinary differential equations, taking into account a white additive and multiplicative noise term, to model random trajectories such as stock market prices or particles movements, on the quantum scale, subject to diffusion phenomena. In rare cases, it is generally impossible to have explicit solution to these equations. In this case, the numerical approach, presenting itself under various aspects, is the only favorable outcome. However, the stability of numerical schemes for stochastic differential equations solution is much more significant. In this paper, we establish and make a classical proof of the mean and mean-square stabilities of the numerical SDEs schemes for Vasicek and Geometric Brownian motion models.

Introduction: Pediatric convulsive status epilepticus (CSE) which is refractory to first-line benzodiazepines is a significant clinical challenge, especially within resource-limited countries. Parenteral phenobarbital is widely used in Africa as second-line agent for pediatric CSE, however evidence to support its use is limited.Purpose: This study aimed to compare the use of parenteral phenobarbital against parenteral phenytoin as a second-line agent in the management of pediatric CSE.Methodology: An open-labeled single-center randomized parallel clinical trial was undertaken which included all children (between ages of 1 month and 15 years) who presented with CSE. Children were allocated to receive either parenteral phenobarbital or parenteral phenytoin if they did not respond to first-line benzodiazepines. An intention-to-treat analysis was performed with the investigators blinded to the treatment arms. The primary outcome measure was the success of terminating CSE. Secondary outcomes included the need for admission to the pediatric intensive care unit (PICU) and breakthrough seizures during the admission. In addition, local epidemiological data was collected on the burden of pediatric CSE.Results: Between 2015 and 2018, 193 episodes of CSE from 111 children were enrolled in the study of which 144 met the study requirements. Forty-two percent had a prior history of epilepsy mostly from structural brain pathology (53%). The most common presentation was generalized CSE (65%) caused by acute injuries or infections of the central nervous system (59%), with 19% of children having febrile status epilepticus. Thirty-five percent of children required second-line management. More patients who received parenteral phenobarbital were at a significantly reduced risk of failing second-line treatment compared to those who received parenteral phenytoin (RR = 0.3, p = 0.0003). Phenobarbital also terminated refractory CSE faster (p < 0.0001). Furthermore, patients who received parenteral phenobarbital were less likely to need admission to the PICU. There was no difference between the two groups in the number of breakthrough seizures that occurred during admission.Conclusion: Overall this study supports anecdotal evidence that phenobarbital is a safe and effective second-line treatment for the management of pediatric CSE. These results advocate for parenteral phenobarbital to remain available to health care providers managing pediatric CSE in resource-limited settings.Attachments: CONSORT 2010 checklistTrial registration: NCT03650270Full trial protocol available:https://clinicaltrials.gov/ct2/show/NCT03650270?recrs=e&type=Intr&cond=Status+Epilepticus&age=0&rank=1

In 1969, upon the advice of the editor, I published my first texts in the Madrilenian daily newspaper ABC under a pseudonym. I was eighteen years old. I had decided [...]

Human African Trypanosomiasis (HAT) and Nagana in cattle, commonly called sleeping sickness, is caused by trypanosome protozoa transmitted by bites of infected tsetse flies. We present a deterministic model for the transmission of HAT caused by Trypanosoma brucei gambiense between human hosts, cattle hosts and tsetse flies. The model takes into account the growth of the tsetse fly, from its larval stage to the adult stage. Disease in the tsetse fly population is modeled by three compartments, and both the human and cattle populations are modeled by four compartments incorporating the two stages of HAT. We provide a rigorous derivation of the basic reproduction number $ \mathcal{R}_{0} $ . For $ \mathcal{R}_{0}1 $ , HAT persists. Elasticity indices for $ \mathcal{R}_{0} $ with respect to different parameters are calculated with baseline parameter values appropriate for HAT in West Africa; indicating parameters that are important for control strategies to bring $ \mathcal{R}_{0} $ below 1. Numerical simulations with $ \mathcal{R}_0 > 1 $ show values for the infected populations at the endemic equilibrium, and indicate that with certain parameter values, HAT could not persist in the human population in the absence of cattle.