On the effects of exothermicity and endothermicity upon the temperature fields in a partially-filled porous channel

Forced convection of heat in a two-dimensional channel, partially filled by a porous insert is considered. This system is assumed under fully developed conditions and constant wall heat flux. Further, the fluid and solid phases can feature internal heat generation (exothermicity) and consumption (endothermicity). Analytical solutions are developed for the solid and fluid temperature fields by applying local thermal non-equilibrium (LTNE) conditions and the Darcy-Brinkman model of momentum transport. Two existing interface models (Models A and B) are employed to describe the thermal boundary conditions at the porous-fluid interface. The developed solutions for the temperature fields are compared to those found by applying the local thermal equilibrium (LTE) assumption and, therefore, the validity of the LTE is examined. This is done for a wide range of pertinent parameters including Biot number, conductivity ratio, Darcy number and thickness of the porous insert. It is found that the thermal behaviour of the investigated partially filled system is influenced by the heat sources in both solid and fluid phase. It is further shown that the LTE approach remains an acceptable assumption only for some specific regions of the parametric space. Furthermore, the occurrence of temperature gradient bifurcation on the surface of the porous-fluid interface is examined. It is demonstrated that this effect is highly sensitive to the intensity of the energy sources

The Influence of Smartphone Over-dependence on the Recall of Basic Mathematics among Mathematics Education Students in a Nigerian University

The results of the study reveal that processes of human memory are adapting to the advent of digital technology, with students displaying low recall of foundational facts and high impatience to quickly rush to the internet in quest of information previously memorized. The findings points to the fact that true mathematical prowess in the current age is only achievable through the conscious effort of the learner in internalizing basic mathematical concepts and regular practice of learnt facts

Socio-economic and Institutional Determinants of Watermelon Marketing in Enugu State, Nigeria

The study analyzed the socio-economic and institutional determinants of watermelon marketing in Enugu state, Nigeria. The specific objectives were to: describe the socio-economic characteristics of watermelon marketers (wholesalers and retailers) and determine the factors influencing the net marketing returns of the marketers. Multistage sampling technique was employed in selecting eight watermelon markets based on the volume of watermelon traded in the markets. Primary data were collected from 160 respondents comprising 96 retailers and 64 wholesalers with the aid of well structured questionnaire. Data collected were analyzed using descriptive statistics and multiple regression model. Results showed that watermelon marketing was dominated by the married (76.25%), literates (97.5%) and females (78.13%) with the mean age and marketing experience of 47 and seven years respectively. The determinants of wholesaler’s net marketing income were product price (0.581) and transportation cost (-2.609), while product price (1.501), educational level (-0.584), storage cost (-0.131), packaging cost (-0.077) and market information (0.057) significantly influenced retailer’s net marketing income. Keywords: Socio-economic, institutional factors, watermelon, marketers, Enugu Stat

Socio-economic and Institutional Determinants of Watermelon Marketing in Enugu State, Nigeria

The study analyzed the socio-economic and institutional determinants of watermelon marketing in Enugu state, Nigeria. The specific objectives were to: describe the socio-economic characteristics of watermelon marketers (wholesalers and retailers) and determine the factors influencing the net marketing returns of the marketers. Multistage sampling technique was employed in selecting eight watermelon markets based on the volume of watermelon traded in the markets. Primary data were collected from 160 respondents comprising 96 retailers and 64 wholesalers with the aid of well structured questionnaire. Data collected were analyzed using descriptive statistics and multiple regression model. Results showed that watermelon marketing was dominated by the married (76.25%), literates (97.5%) and females (78.13%) with the mean age and marketing experience of 47 and seven years respectively. The determinants of wholesaler’s net marketing income were product price (0.581) and transportation cost (-2.609), while product price (1.501), educational level (-0.584), storage cost (-0.131), packaging cost (-0.077) and market information (0.057) significantly influenced retailer’s net marketing income. Keywords: Socio-economic, institutional factors, watermelon, marketers, Enugu Stat

Combating Antimalarial Drug Resistance: Recent Advances and Future Perspectives

This chapter X-rayed antimalarial drug resistance (ADR) by plasmodium species with a particular focus on P. falciparum, which is the most deadly species of the malaria parasite responsible for over 90% of the global malaria burden domiciled in Sub-Saharan Africa. The introduction intently looked at malaria therapeutics across the decades and the development of drug resistance by the parasite. With the malaria parasite (P. falciparum) as the focal point, the mechanisms by which they develop resistance to antimalarial drugs was looked at, including factors affecting drug resistance development. Armed with this knowledge, the chapter also highlighted the therapeutic interventions taken against this hydra-headed monster together with their limitations and recent advances towards addressing those limitations or opening new frontiers for research exploration. Future perspectives that will provide research strategy and direction as possible tools for combating drug resistance development by the malaria parasite were also discussed

IPSE, an abundant egg-secreted protein of the carcinogenic helminth Schistosoma haematobium, promotes proliferation of bladder cancer cells and angiogenesis

Background Schistosoma haematobium, the helminth causing urogenital schistosomiasis, is a known bladder carcinogen. Despite the causal link between S. haematobium and bladder cancer, the underlying mechanisms are poorly understood. S. haematobium oviposition in the bladder is associated with angiogenesis and urothelial hyperplasia. These changes may be pre-carcinogenic events in the bladder. We hypothesized that the Interleukin-4-inducing principle of Schistosoma mansoni eggs (IPSE), an S. haematobium egg-secreted “infiltrin” protein that enters host cell nuclei to alter cellular activity, is sufficient to induce angiogenesis and urothelial hyperplasia. Methods: Mouse bladders injected with S. haematobium eggs were analyzed via microscopy for angiogenesis and urothelial hyperplasia. Endothelial and urothelial cell lines were incubated with recombinant IPSE protein or an IPSE mutant protein that lacks the native nuclear localization sequence (NLS-) and proliferation measured using CFSE staining and real-time monitoring of cell growth. IPSE’s effects on urothelial cell cycle status was assayed through propidium iodide staining. Endothelial and urothelial cell uptake of fluorophore-labeled IPSE was measured. Findings: Injection of S. haematobium eggs into the bladder triggers angiogenesis, enhances leakiness of bladder blood vessels, and drives urothelial hyperplasia. Wild type IPSE, but not NLS-, increases proliferation of endothelial and urothelial cells and skews urothelial cells towards S phase. Finally, IPSE is internalized by both endothelial and urothelial cells. Interpretation: IPSE drives endothelial and urothelial proliferation, which may depend on internalization of the molecule. The urothelial effects of IPSE depend upon its NLS. Thus, IPSE is a candidate pro-carcinogenic molecule of S. haematobium. Summary Schistosoma haematobium acts as a bladder carcinogen through unclear mechanisms. The S. haematobium homolog of IPSE, a secreted schistosome egg immunomodulatory molecule, enhances angiogenesis and urothelial proliferation, hallmarks of pre-carcinogenesis, suggesting IPSE is a key pro-oncogenic molecule of S. haematobium

The use of plants in the traditional management of diabetes in Nigeria: Pharmacological and toxicological considerations

Ethnopharmacological relevance: The prevalence of diabetes is on a steady increase worldwide and it is now identified as one of the main threats to human health in the 21st century. In Nigeria, the use of herbal medicine alone or alongside prescription drugs for its management is quite common. We hereby carry out a review of medicinal plants traditionally used for diabetes management in Nigeria. Based on the available evidence on the species׳ pharmacology and safety, we highlight ways in which their therapeutic potential can be properly harnessed for possible integration into the country׳s healthcare system. Materials and methods: Ethnobotanical information was obtained from a literature search of electronic databases such as Google Scholar, Pubmed and Scopus up to 2013 for publications on medicinal plants used in diabetes management, in which the place of use and/or sample collection was identified as Nigeria. ‘Diabetes’ and ‘Nigeria’ were used as keywords for the primary searches; and then ‘Plant name – accepted or synonyms’, ‘Constituents’, ‘Drug interaction’ and/or ‘Toxicity’ for the secondary searches. Results: The hypoglycemic effect of over a hundred out of the 115 plants reviewed in this paper is backed by preclinical experimental evidence, either in vivo or in vitro. One-third of the plants have been studied for their mechanism of action, while isolation of the bioactive constituent(s) has been accomplished for twenty three plants. Some plants showed specific organ toxicity, mostly nephrotoxic or hepatotoxic, with direct effects on the levels of some liver function enzymes. Twenty eight plants have been identified as in vitro modulators of P-glycoprotein and/or one or more of the cytochrome P450 enzymes, while eleven plants altered the levels of phase 2 metabolic enzymes, chiefly glutathione, with the potential to alter the pharmacokinetics of co-administered drugs. Conclusion: This review, therefore, provides a useful resource to enable a thorough assessment of the profile of plants used in diabetes management so as to ensure a more rational use. By anticipating potential toxicities or possible herb–drug interactions, significant risks which would otherwise represent a burden on the country׳s healthcare system can be avoided

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication

Sustaining Attention in a Rapidly Changing World: A Survey of the Status among Mathematics Education Students in Nigeria

Mathematics education, along with its processes and outcomes, is not left out in the impact of the technological change resonating across the globe. This survey was designed to ascertain the status quo in attention management by mathematics education students in Nigeria in the face of present-day unlimited liberties and possibilities

Sustaining Attention in a Rapidly Changing World: A Survey of the Status among Mathematics Education Students in Nigeria

International audienceMathematics education, along with its processes and outcomes, is not left out in the impact of the technological change resonating across the globe. This survey was designed to ascertain the status quo in attention management by mathematics education students in Nigeria in the face of present-day unlimited liberties and possibilities. Two instruments, the Dispositional In-Class Inattentiveness Questionnaire for Mathematics Education Students (DICIQ-MES) and the Smartphone Addiction Scale – Short Version (SAS-SV), were used to measure the students’ levels of inattentiveness and smartphone addiction respectively. The instruments were administered to a sample of 105 mathematics education students at a University in North Central Nigeria. The findings of this study revealed a considerably low level of dispositional in-class inattentiveness and a moderately low level of smartphone addiction among mathematics education students. The study also established a statistically significant positive relationship between smartphone addiction and dispositional in-class inattentiveness among the students. Considering the outcome that attention management is becoming one of the most important skills for learners in this era, this study upholds that mathematics educators teach today’s students how to manage and direct their attention to enable them become successful learners