Comparative performance of agricultural productivity in 44 SSA countries for a period of 59 years (1961-2019): A Malmquist productivity index approach.

We investigate the extent and nature of productivity growth in Sub-Saharan African countries using non-parametric frontier techniques. In this work, we examine agricultural total factor productivity (TFP) change in 44 countries in Sub-Saharan Africa (SSA), covering a period of fifty-nine (59) years (1961-2019). We make use of data drawn from the Food and Agriculture Organization of the United Nations. Due to the non-availability of reliable input price data, the study uses data envelopment analysis (DEA) to derive Malmquist productivity indices. The results demonstrate a decline in agricultural TFP growth in the region from 1961 to 2019. This notwithstanding, a general average growth was seen in some of the conventional inputs measured (land, labour, capital, and fertilizer) which are the main drivers of growth in the region. This finding implies that the increase in agricultural output over the past five decades in SSA is mainly due to an increased use of conventional inputs over time, including land, and not due to an increase in the ratio of output over inputs. As a generally acceptable and preferred indicator of technical and efficiency changes, we use TFP to calculate the Malmquist productivity index (MPI).

Efficient Water Collection from Biodesigned and Natural Inclined Surfaces: Influence of Inclination Angle on Atmospheric Water Collection.

Water is one of the most important and crucial indicators of sustainable development goals (SDGs) for humans and other living organisms. Water demand has outstripped supply, resulting in shortage on a worldwide scale, particularly in arid regions. This water scarcity has impeded agricultural productivity and other developmental projects with the ongoing global warming and other anthropogenic activities making it more complicated. To address the worldwide water crisis, it is worthwhile to convert atmospheric air to drinking water. Sequel to that, a hydrophobic surface was designed using facile lithography to compare its water harvesting efficiency with a hydrophilic surface at different orientation angles. For the research, the hydrophobic designed surface is called biodesigned material, while the hydrophilic natural surface is a Mangifera indica leaf (MIL). It is against this background that we seek to investigate the most suitable orientation angle good for efficient water harvesting. To that end, a 60° inclination angle is the most efficacious orientation for water collection as it outperformed the 30 and 45° orientation angles. To minimize re-evaporation, absorption, suction, and other environmental challenges that impede efficient collection, atmospheric moisture should be collected immediately from functional surfaces.

Biotemplate Replication of Novel Mangifera indica Leaf (MIL) for Atmospheric Water Harvesting: Intrinsic Surface Wettability and Collection Efficiency.

Water shortage has become a global crisis that has posed and still poses a serious threat to the human race, especially in developing countries. Harvesting moisture from the atmosphere is a viable approach to easing the world water crisis due to its ubiquitous nature. Inspired by nature, biotemplate surfaces have been given considerable attention in recent years though these surfaces still suffer from intrinsic trade-offs making replication more challenging. In the design of artificial surfaces, maximizing their full potential and benefits as that of the natural surface is difficult. Here, we conveniently made use of Mangifera indica leaf (MIL) and its replicated surfaces (RMIL) to collect atmosphere water. This research provides a novel insight into the facile replication mechanism of a wettable surface made of Polydimethylsiloxane (PDMS), which has proven useful in collecting atmospheric water. This comparative study shows that biotemplate surfaces (RMIL) with hydrophobic characteristics outperform natural hydrophilic surfaces (DMIL and FMIL) in droplet termination and water collection abilities. Water collection efficiency from the Replicated Mangifera indica leaf (RMIL) surface was shown to be superior to that of the Dry Mangifera indica leaf (DMIL) and Fresh Mangifera indica leaf (FMIL) surfaces. Furthermore, the wettability of the DMIL, FMIL, and RMIL was thoroughly investigated, with the apices playing an important role in droplet roll-off.

Mangifera indica Leaf (MIL) as a Novel Material in Atmospheric Water Collection.

Here, Mangifera indica leaves (MILs) have been used to collect atmospheric water for the first time. This novel material has been viewed by mankind as environmental waste and is mostly discarded or incinerated, causing environmental pollution. By turning waste into wealth, MILs have proven resourceful and can help ameliorate the water crisis, especially in tropical countries. The unprecedented water collection result is enough to describe MILs as an ideal material for atmospheric water collection when compared to other natural plants. Both the physical and chemical surface morphologies were extensively characterized. This comparative study shows that MIL surface droplet termination and hydrophilic nature differ from those of other materials, with the apex playing a key role in the roll-off of the droplet. The surface wettability and its interaction with the droplet are of keen interest in this study.