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The purpose of this paper is to assess the extent to which adaptation projects have incorporated ecosystem services, as well as their redesigning options. The projects selected are listed under National Adaptation Programme of Action in West African region.

A desktop survey approach was used to review 168 projects from 13 countries across West Africa. The projects were categorized and analyzed according to their adaptation goal, thematic focus, their implementation duration and level of investment.

The adaptation initiatives are dominated by actions in the agricultural sector accounting for 32 per cent of the total. Further, they were characterized by small grants consideration with 63 per cent falling under US$1m budget, short-term implementation duration with 46 per cent having three years’ execution period. A large portion of projects (55 per cent) mentioned directly one or more ecosystem services, with provisioning services being referred to in 50 per cent of the cases.

Adaptation projects with ecosystem services components are more sustainable and beneficial to the community. Hence, more consideration of nature benefits during project design, more financial consideration and localizing of the projects to realize the global adaptation goal should be considered.

The purpose of this paper is to study the transient natural convection of a Newtonian fluid which develops in a closed spherical annulus delimited by two vertically eccentric spheres by using a bispherical coordinates system. The inner sphere is heated by a heat flux of constant density and the outer one is maintained isothermal.

The transfer equations are written by using a bispherical coordinates system. The Navier‐Stokes equations are solved and coupled with the energy equation by using the alternating direction implicit (ADI) and the successive over relaxation (SOR) methods.

The study of the stream function and the Nusselt number shows that the convection motion is reinforced for the geometries characterized by positive values of the eccentricity with heat exchange increasing. The Nusselt number increases with the modified Rayleigh number. The heat exchange increases with the radius ratio. The results show that the steady state is reached faster when the modified Rayleigh number increases and the influence of the eccentricity is very low on the establishment of the steady state. The fluids flow depends strongly on the eccentricity and the modified Rayleigh number.

Simulations are performed for modified Rayleigh numbers ranging from 10³ to 10⁶, for eccentricities varying between –0.6 and +0.6 and for radius ratio between 1.5 and 2.

The results of eccentricity and modified Rayleigh number effects in transient natural convection between vertically eccentric spheres have been displayed.

The effect of radiation on unsteady natural convection in a two‐dimensional participating medium between two horizontal concentric and vertically eccentric cylinders is investigated numerically. The equations of transfer are written by using a bicylindrical coordinates system, the stream function, and the vorticity. The finite volume radiation solution method and the control volume approach are used to discretize the coupled equations of radiative transfer, momentum, and energy. Original results are obtained for three eccentricities, Rayleigh number equal to 10⁴, 10⁵, and a wide range of radiation‐conduction parameter. The effects of optical thickness, wall emissivity, and scattering on flow intensity and heat transfer are discussed.

The purpose of this paper is to compare the numerical laminar two‐dimensional unsteady natural convection in a partial sector‐shaped enclosure submitted respectively to a constant heat flux density q1 and a uniform temperature T1 on the inner cylindrical wall. The numerical model performed in this paper is applied more particularly for high Grashof numbers, in order to point out the advent and the development of pre‐turbulent flows. Results of numerical runs are presented. The mean Nusselt number on active walls is represented as a function of the Grashof number Gr and the aspect ratio F_r. The results may be correlated very well with an expression of the form \overlineNu = k1 Gr₁^k2, for technical calculations.

The paper aims to compare the return on Mudhārabah deposits (ROMD) to the return on equity (ROE) in Islamic banks.

The summary statistics of the ROMD and the ROE is used to make a comparison between them with a sample of nine Islamic banks, from seven countries, over the last five years. Regression analysis is also undertaken to unveil the variables affecting the behaviour of ROMD and ROE at Kuwait Finance House.

The results show that the ROE tend to be at least two times higher than the ROMD. In most of the investigated cases the ROMD are more correlated to the corresponding conventional interest rate than to ROE. The regression analysis suggests that the return on assets affects more significantly the ROE than the ROMD.

The originality of the paper resides in the size of the sample and in the design and the findings.