Buoyancy and thermal radiation effects for the Blasius and Sakiadis flows with a convective surface boundary condition

This study is devoted to investigate the Buoyancy and thermal radiation effects on the laminar boundary layer about a flat-plate in a uniform stream of fluid (Blasius flow), and about a moving plate in a quiescent ambient fluid (Sakiadis flow) both under a convective surface boundary condition. Using a similarity variable, the governing nonlinear partial differential equations have been transformed into a set of coupled nonlinear ordinary differential equations, which are solved numerically by using shooting technique along side with the sixth order of Runge-Kutta integration scheme and the variations of dimensionless surface temperature and fluid-solid interface characteristics for different values of Prandtl number Pr, radiation parameter NR, parameter a and the local Grashof number Grx, which characterizes our convection processes are graphed and tabulated. Quite different and interesting behaviours were encountered for Blasius flow compared with a Sakiadis flow. A comparison with previously published results on special cases of the problem shows excellent agreement

Effects of chemical reaction, thermal radiation, internal heat generation, Soret and Dufour on chemically reacting MHD boundary layer flow of heat and mass transfer past a moving vertical plate with suction/injection

In the present analysis, we study the two-dimensional, steady, incompressible electrically conducting, laminar free convection boundary layer flow of a continuously moving vertical porous plate in a chemically reactive medium in the presence of transverse magnetic field, thermal radiation, chemical reaction, internal heat generation and Dufour and Soret effect with suction/injection. The governing nonlinear partial differential equations have been reduced to the coupled nonlinear ordinary differential equations by the similarity transformations. The problem is solved numerically using shooting techniques with the sixth order Runge-Kutta integration scheme. Comparison between the existing literature and the present study were carried out and found to be in excellent agreement. The influence of the various interesting parameters on the flow and heat transfer is analyzed and discussed through graphs in detail. The values of the local Nusselt number, Skin-friction and the Sherwood number for different physical parameters are also tabulated. Comparison of the present results with known numerical results is shown and a good agreement is observed

Effects of Ohmic Heating,Radiation and Viscous Dissipation on Steady MHD Flow Near a Stagnation Point on an Isothermal Stretching Sheet in the Presence of Heat Generation

Aim of the paper is to examine the influences of radiation, heat generation, Ohmic heating and viscous dissipation on steady flow of a viscous incompressible electrically conducting fluid in the presence of uniform transverse magnetic field and variable free stream near a stagnation point on a stretching non-conducting isolhennal sheet. The governing equations of continuity, momentum, and energy are transformed into ordinary differential equations and solved numerically by shooting method alongside with Runge-Kutta sixth order. The velocity and temperature profiles are extensively discussed numerically and presented with the aid of graphs. Skin-friction coefficient and the Nusselt number at the sheet are derived, discussed and their numerical values for various values of physical parameters are COf11lared with the existing literature in tabular form and there are perfect agreements

Reform in a Limbo: The Politics and Politicization of Reforms in Nigeria’s Petroleum Sector

Nigeria has been on a long-winding journey to reform its petroleum sector with no end in sight. The first version of the reform bill, the petroleum industry bill (PIB) was sent to the National Assembly in 2008. The sustained opposition to the PIB from both indigenous and international oil companies as well as other stakeholders led to the decision, in 2016, to balkanize it into four bills, with each bill focusing on an aspect of the reform. The first of the quadripartite bills, the petroleum industry governance bill (PIGB) was passed by both chambers of Nigeria’s National Assembly and transmitted to the president for assent. The president declined assent, thus deepening the uncertainty that characterizes the sector. Drawing data from primary and secondary sources, the paper evaluates the trajectory of Nigeria’s petroleum sector reform, including the long delay and its impact on the sector. It finds that the delay in passing the reform bills has negatively rubbed off on the country as it has stymied growth and closed off new investments. The paper advocates the depoliticization of the reform agenda in order to reposition the country’s petroleum sector for national development

Prolonged use of indwelling urinary catheter following acute urinary retention in a tertiary care centre in sub-Saharan Africa: Causes, costs and concerns

Objectives: To evaluate the causes, estimate out-of-pocket payments and assess concerns associated with prolonged use of urinary catheters following acute urinary retention secondary to benign prostate enlargement (BPE) and urethral stricture disease (USD) in men attending the urology out-patient clinic of a tertiary referral centre in North-central Nigeria. Patients and methods: This was a cross-sectional survey of men attending urology clinic and who are using indwelling urinary catheter for >3 months following acute urinary retention due to BPE or USD. The study was conducted over a six-month period (1st March 2012 to 31st August 2012) at a tertiary hospital in North-central Nigeria using interviewer administered questionnaires. Results: Of seventy-six men, 36/76 (47.4%) had BPE and 40/76 (52.6%) had USD. Median age, median duration of catheter use and median out-of-pocket payment per catheter change was 65 years (range 20–90 years), 12 months (range 3–120 months) and US$9.31 (range$3.63–18.75) respectively. There was no significant difference in the duration of catheter use and out-of-pocket payments between men with BPE and USD; however, men with USD were significantly younger than those with BPE. One-fifth and half of the men with BPE and USD, respectively attributed inability to pay for surgery as the reason for prolonged use of catheters. The second common reason was long waiting list for surgery. Men with BPE had their sexual relationships disrupted significantly more than those with USD and unexpectedly, we found that men using catheters for less than 6 months describe themselves as unhappy significantly more than those using the catheters for longer periods (p = 0.033). Conclusions: Inability to pay for definitive surgery and long waiting lists are the leading causes of prolonged use of indwelling urinary catheters in men with BPE and USD in our sub-Saharan setting. Prolonged catheter use adversely affected quality of life disrupting sexual relationships especially of men with BPE. Recommendations made to reduce out-of-pocket payments and shorten waiting times may help to improve access to urologic surgical care for these men

Cálcio, fósforo e proteína total no sangue de frangos de corte em função de níveis de balanço eletrolítico da ração

Determinaram-se os melhores valores do balanço eletrolítico (BE) de dietas para frangos quanto aos teores de cálcio, fósforo e proteína total no sangue de frangos de corte aos 42 dias de idade. Foram utilizadas 1728 aves de marca comercial, machos. As aves foram alimentadas com duas dietas basais, 20 ou 23% de proteína bruta (PB), na fase inicial, e uma única ração basal, 20% de PB, na fase de crescimento, combinadas com níveis de balanço eletrolítico de 0; 50; 100; 150; 200; 250; 300 e 350mEq/kg. Foi utilizado delineamento experimental inteiramente ao acaso, em arranjo fatorial, com seis repetições de 18 aves cada e 96 unidades experimentais. Foi escolhida uma ave em cada unidade experimental para a coleta de sangue. Foram avaliados os teores de cálcio, fósforo e proteínas totais no sangue dessas aves aos 42 dias de idade. Os melhores valores de BE estimados para o teor de proteína total no sangue foram de 101 e 131mEq/kg da dieta, para planos nutricionais de 20-20% e 23-20% de PB, respectivamente. Para os teores plasmáticos de cálcio e fósforo, não foram encontradas diferenças entre os níveis de BE estudados