Brownian motion near a partial-slip boundary: A local probe of the no-slip condition

Motivated by experimental evidence of violations of the no-slip boundary condition for liquid flow in micron-scale geometries, we propose a simple, complementary experimental technique that has certain advantages over previous studies. Instead of relying on externally-induced flow or probe motion, we suggest that colloidal diffusivity near solid surfaces contains signatures of the degree of fluid slip exhibited on those surfaces. To investigate, we calculate the image system for point forces (Stokeslets) oriented perpendicular and parallel to a surface with a finite slip length, analogous to Blake's solution for a Stokeslet near a no-slip wall. Notably, the image system for the point source and perpendicular Stokeslet contain the same singularities as Blake's solution; however, each is distributed along a line with a magnitude that decays exponentially over the slip length. The image system for the parallel Stokeslet involves a larger set of fundamental singularities, whose magnitude does not decay exponentially from the surface. Using these image systems, we determine the wall-induced correction to the diffusivity of a small spherical particle located `far' from the wall. We also calculate the coupled diffusivities between multiple particles near a partially-slipping wall. Because, in general, the diffusivity depends on `local' wall conditions, patterned surfaces would allow differential measurements to be obtained within a single experimental cell, eliminating potential cell-to-cell variability encountered in previous experiments. In addition to motivating the proposed experiments, our solutions for point forces and sources near a partial-slip wall will be useful for boundary integral calculations in slip systems.Comment: 34 pages, 5 figure

Significance of Kaduna River to Kaduna Refining and Petrochemicals Complex: Some Checks and Balances

Kaduna Refinery and Petrochemicals Complex comprises of variousprocessing units. The plants produce various grades of petroleum andpetrochemical products. But in all of the plants and facilities, water isrequired in its various forms. The paper describes Desalter Process andRefinery Wastewater. The only major source of water is Kaduna River. TheChemical compositions of the raw and filtered water differ. The compositionsof the treated and “imported” bottled waters are the same and thus fit fordrinking. pH value is fairly constant and so also other elements. Purificationis by demineralization using ion-exchange resins. Demineralised watercontains a number of chemicals and compounds. The process waters aredischarged either as steam or drained out as affluent water. The Sour WaterStripper (SWS) is not functioning. Consequently, the polluted wastewater isdischarged directly to the environment. The Sour Water Stripper must beresuscitated and made to function. Government and KRPC would need toinform and educate members of the community about the effluent wastewaterand its consequences in the environment. Ultra Filtration Membrane Systemis recommended for treatment of desalter effluent

Government Amnesty Programme and Peace Efforts in the Niger Delta Region: An Analysis of Newspapers’ Coverage

Nigeria has undergone not a few crises since the country gained political independence from Great Britain in 1960. One of the current crises is the agitation of the youths of the oil-rich Niger Delta region for the control of oil and gas resources located in their region. In a bid to stem down the tide of violent activities and its attendant obstruction of the economic development of not only the region but also that of the nation at large, the government introduced what it termed "Presidential Amnesty Programme". This paper examined the newspapers' coverage of the situation in the Niger Delta region at a period considered the peak of the crisis, that is 2007 and 2009 as well as the coverage of the situation during the amnesty period (from 6th August to 4th October 2009). Content analysis was employed for this study. The study period was divided into two, that is, pre- amnesty period and amnesty period. Two popular national daily newspapers were examined, that is the Punch and the Guardian newspapers. A total number of three hundred and two copies of the two newspapers selected for the study were content analyzed. One hundred and eighty two were examined for the first period and one hundred and twenty copies were looked into for the second period. Social responsibility theory was considered relevant to the study. It was discovered that violent activities were well pronounced before the commencement of amnesty programme. 47.8 percent of the newspapers content on the region for the period was on violent activities such as vandalism of oil installations, violent attacks on oil workers and kidnappings. However, "Presidential Amnesty Programme" significantly reduced tension as well as crime in the region. Only 13 percent of all the stories published in the two newspapers during the amnesty programme were on violence. Huge numbers of the former militants (about 30,000) embraced reconciliation and rehabilitation. Amnesty programme so far has proved to be huge success

Bridelia ferruginea Produces Anti-neuroinflammatory Activity through Inhibition of Nuclear Factor-kappa B and p38 MAPK Signalling

Bridelia ferruginea is commonly used in traditional African medicine (TAM) for treating various inflammatory conditions. Extracts from the plant have been shown to exhibit anti-inflammatory property in a number of in vivo models. In this study the influence of B. ferruginea (BFE) on the production of PGE2, nitrite, and proinflammatory cytokines from LPS-stimulated BV-2 microglia was investigated. The effects of BFE on cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) protein expressions were evaluated in LPS-activated rat primary microglia. The roles of NF-κB and MAPK signalling in the actions of BFE were also investigated. BFE (25–200 μg) inhibited the production of PGE2, nitrite, tumour necrosis factor-α (TNFα), and interleukin-6 (IL-6) as well as COX-2 and iNOS protein expressions in LPS-activated microglial cells. Further studies to elucidate the mechanism of anti-inflammatory action of BFE revealed interference with nuclear translocation of NF-κBp65 through mechanisms involving inhibition of IκB degradation. BFE prevented phosphorylation of p38, but not p42/44 or JNK MAPK. It is suggested that Bridelia ferruginea produces anti-inflammatory action through mechanisms involving p38 MAPK and NF-κB signalling

Spatio-Temporal Variation in Water Quality of Orle River Basin, S.W. Nigeria

The water quality of small streams in Auchi area of Edo State, S.W. Nigeriawas investigated with a view to ascertaining the toxicity levels of the waterand its impact on the human and ecosystems. The study was carried outbetween November 1987 and June 1988 at a two weekly intervals for aperiod of eight months. The elements investigated include the major cations of Calcium (Ca++), Magnesium (Mg++) Sodium (Na+), Potassium (K+), and hydrogen-ion concentration (pH). Results indicated that Calcium (Ca++), Sodium (Na+) and hydrogen-ion concentration (pH) showed significant variation in the various rock types. Also Calcium (Ca++), Sodium (Na+) and Potassium (K+) showed significant variation with pH. However, Sodium (Na+), Potassium (K+), Magnesium (Mg++) and Hydrogen-ion concentration (pH) showed no definite pattern of variation. This paper focuses on this aspect of Orle River, thus giving baseline information on the temporal and spatial dynamics in the chemical attributes of the basin. This is necessary since the rivers form a major source of drinking water for the communities living within the area. At present, the natives treat the water with alum before use.Key Words: elements, calcium, magnesium, sodium, potassium

Inspiration of Technology; Effect of COVID-19 Pandemic on Education

Just like every other virus, there is a recent outbreak of COVID-19 which hampers with the school academic activities. This virus been an influenza, epidemic and airborne disease had affected a lot of lives, affecting national economy as well as shutting down all schools at all levels. Thus, there is a need to introduce technologies which can help students continue with their learning from their different isolation centres. The present study investigated (i) various technologies that can be used for learning from their isolation centres; (ii) influence of these technologies in combating the learning gaps established by COVID-19; and (iii) readiness of students to use these technologies. It was concluded that mobile learning, google classroom, webinar zoom application and web-based authoring system among others can be used to resolve the academic activity crisis established via the pandemic but clustered teaching is apt for those without access to versatile technologies and electricity power supply. Thus, if these technologies are utilized by students and teachers for both the teaching and learning process, there could be tremendous improvement in the academic performance of students as well as job performance of the teachers across all levels of education

Electronic Prescription System for Pediatricians

This paper presents the development of an electronic prescription system for pediatricians that considered the factors that influence a child’s prescription. The system implements a knowledge base which contains drug information and formulary. It allows the pediatrician to have access to the electronic health record of patients before prescription writing. The resulting prescription is marked with verifiable randomly generated prescription ID before it is sent to the dispensing pharmacy and this accounts for the security feature of the prescription system. Microsoft Office Visio 2007, PHP and My SQL database server were used to present and develop the system. Implementation results showed the system is capable of reducing common prescription error as the most informed prescription is being generated for the child electronically

Isolation and characterization of antioxidant and antimicrobial compounds from Anacardium occidentale L. (Anacardiaceae) leaf extract

AbstractThe extracts obtained from Anacardium occidentale leaf were investigated for antioxidant and antimicrobial activities. Bioassay-guided fractionation using DPPH autobiographic analysis of the EtOAc soluble fraction of the crude extract resulted in the isolation of agathisflavone (1) and a mixture of quercetin 3-O-rutinoside (2) and quercetin 3-O-rhamnoside (3). Characterization of the isolated compounds was carried out using nuclear magnetic resonance (1D and 2D) and mass spectrometry. The antioxidant activities of the samples were determined using three complementary tests, namely; DPPH-radical scavenging, total antioxidant capacity (TAC) and ferric reducing antioxidant power (FRAP). The antimicrobial activity of the samples was evaluated using the disc diffusion and broth microdilution methods. The results indicated that the mixture (ratio 2:1) of compounds (2) and (3) was most active in its capacity to scavenge free radicals in the DPPH assay [IC50=0.96±0.01μg/mL] compared to the ethyl acetate (EtOAc) fraction, the ascorbic acid and quercetin standards. The mixture of compounds (2) and (3) exhibited the highest activities in the TAC assay (5332.00±3.38mgAAE/g, 8562.00±5.43mgQE/g) and FRAP assay (15,136.00±7.14mgAAE/g, 199,530.00±94.12mgQE/g) compared to the EtOAc fraction. The fractions of the extract showed comparatively better activities against gram-negative than the gram positive ones with the broadest spectrum of activities demonstrated for the ethyl acetate fraction. No inhibitions were obtained against the fungal strains investigated. The isolated compounds from the plant possess essentially inhibitory rather than cidal activities against these organisms with the Minimum Bactericidal Concentrations (MBCs) >2.0mg/mL in all cases. The mixture of compounds 2 and 3 showed higher activity than compound 1 with the former having MIC as low as 0.25mg/mL against Pseudomonas aeruginosa and Clostridium sporogens, 0.5mg/mL against Staphylococcus aureus and 1.0mg/mL against Escherichia coli and Klebsiella pneumonia strains investigated while the latter has an MIC of 1.0mg/mL against most of the organisms.This study concluded that the extracts and isolated compounds had strong antioxidant and moderate antibacterial activities and could be effective in the management of oxidative stress related diseases. These findings also justified the use of this plant’s extracts in folk medicine

Assessment and predictors of blood glucose levels in hypertensives attending a secondary health centre: relationship with physical activity and diet quality

The aim: this study aims to assess the prevalence of hyperglycaemia, the association between diet quality, physical exercise and blood glucose levels among hypertensives attending a secondary health centre in Nigeria. There is a paucity of data concerning these issues and the study would contribute positively to future management of the patients. Methods: the study was a cross-sectional study of 354 hypertensives that was conducted at the State Hospital, Oyo, Nigeria. The systematic sampling technique was used to recruit patients, and the data were analysed using SPSS software version 23. Linear regression was done to determine the predictors of hyperglycaemia, and logistic regression was done to determine the predictors of diet quality. Results: the mean age of the respondents was 52.60(SD±8.26) years. The prevalence of undiagnosed diabetes in this cohort was 19.60 %. The association of glycated haemoglobin (HbAic) with High Density Lipoprotein (HDL) was negative, weak in strength and statistically significant (p-value=0.034). For every 1 unit decrease in High Density Lipoprotein (HDL), there was a statistically significant increase in HbAic by about 0.383 units (95 % C.I equals -0.737 to -0.029, p-value=0.034). For every 1 unit increase in total Cholesterol, there was a significant increase in HbAic by about 0.158 units (95 % CI equals 0.007 to 0.308, p-value=0.04). Age group <45 years were about 2 times less likely to have good diet quality than those of 55 years and above (OR=0.502; 95 % CI=0.270 – 0.932, p-value=0.029). Conclusions: the study has assisted to characterise this population of hypertensives in terms of serum glucose levels. The prevalence of hyperglycaemia was high among these hypertensives. The predictors of hyperglycaemia were HDL and Cholesterol. Also, the predictor of good diet quality was the age of the respondent