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This paper aims to review the current status of wheat production, farming systems, production constraints and wheat demand-supply chain analysis; the role of international and national breeding programs and their approaches in wheat genetic improvement including targeting mega environments, shuttle breeding, doubled haploids, marker-assisted selection and key location phenotyping; and future prospects and opportunities of wheat production in Sub Saharan Africa (SSA).

Relevant literature works have been used and cited accordingly.

Though traditionally wheat was not the leading staple crop in SSA, it is becoming an important food crop because of rapid population growth associated with increased urbanization and change in food preference for easy and fast food such as bread, biscuits, pasta, noodles and porridge. In 2013, total wheat consumption in SSA reached 25 million tons with import accounting for 17.5 million tons at a price of USD6 billion, while during the same period the region produces only 7.3 million tons on a total area of 2.9 million hectares. The low productivity (2t/ha) in the region is principally because of abiotic (drought and heat) and biotic (yellow rust, stem rust, septoria and fusarium) stresses which are increasing in intensity and frequency associated with climate change. Furthermore, increased cost of production, growing populations, increased rural-urban migration, low public and private investments, weak extension systems and policies, and low adoption rates of new technologies remain to be major challenges for wheat production in SSA. Wheat breeding in SSA is dominantly carried out by National Agricultural Research Systems, in partnership with the international research centers [International center for improvement of maize and wheat (CIMMYT) and International center for agricultural research in the dry areas (ICARDA)], to develop high yielding and widely adapted wheat genotypes with increased water-use efficiency, heat tolerance and resistance to major diseases and pests. Most of the cultivars grown in SSA are originated from the international research centers, CIMMYT and ICARDA.

This paper will help to promote available wheat technologies in SSA by creating awareness to wheat scientists, extension agents and policymakers.

This manuscript is an original review paper which has not been published in this form elsewhere.

The purpose of this paper is to examine the effect of support price on wheat production in Pakistan during the period 1971–2016.

To capture the effect of support price on wheat production, the authors estimated the long-run linkage by using the ARDL bounds testing approach to cointegration.

This study confirmed the presence of a positive and long-term effect of area under cultivation, support price and fertilizer consumption on wheat production through ARDL bounds test. The results showed that both in the long run and short run, support price plays an important role in the enhancement of wheat production. The authors also found that the coefficients of the area under cultivation and fertilizer consumption variables were statistically significant and positive both in the long run and short run.

The use of the ARDL approach that examines the long-run and short-run effects of support price on wheat production in Pakistan makes the current study unique. An emerging economic literature suggests that only limited research has been conducted in this area.

This study aims to analyse the non-linear losses of a porous media (stack) composed by parallel plates and inserted in a resonator tube in oscillatory flows by proposing numerical correlations between pressure gradient and velocity.

The numerical correlations origin from computational fluid dynamics simulations, conducted at the microscopic scale, in which three fluid channels representing the porous media are taken into account. More specifically, for a specific frequency and stack porosity, the oscillating pressure input is varied, and the velocity and the pressure-drop are post-processed in the frequency domain (Fast Fourier Transform analysis).

It emerges that the viscous component of pressure drop follows a quadratic trend with respect to velocity inside the stack, while the inertial component is linear also at high-velocity regimes. Furthermore, the non-linear coefficient b of the correlation ax + bx² (related to the Forchheimer coefficient) is discovered to be dependent on frequency. The largest value of the b is found at low frequencies as the fluid particle displacement is comparable to the stack length. Furthermore, the lower the porosity the higher the Forchheimer term because the velocity gradients at the stack geometrical discontinuities are more pronounced.

The main novelty of this work is that, for the first time, non-linear losses of a parallel plate stack are investigated from a macroscopic point of view and summarised into a non-linear correlation, similar to the steady-state and well-known Darcy–Forchheimer law. The main difference is that it considers the frequency dependence of both Darcy and Forchheimer terms. The results can be used to enhance the analysis and design of thermoacoustic devices, which use the kind of stacks studied in the present work.

Recent studies have shown that the contribution of small firms to employment and GDP is increasing. A large amount of work has also established the significance of social and economic variables for entrepreneurial decisions. Very little is known, however, about how government policies and programs influence entrepreneurial activity, and whether these effects are consistent across countries. Using original data from a representative sample of 10,000 individuals and from more than 300 open-ended interviews in 10 countries, this article provides some suggestive evidence that government intervention aimed at enhancing the underlying environment of entrepreneurial decisions may be more effective than intervention designed to provide safety nets.

Using the Panel Study of Entrepreneurial Dynamics II dataset, we examine the role that household income plays in the emergence of consumer-oriented start-ups by individual (solo), family-based (family), and non-family based start-ups (team). In particular, we address the research question: Does household income impact firm emergence, and if so, is emergence impacted differently based on start-up configuration? Our results indicate that household income does have a significant impact on average firm emergence, as well as on emergence growth rates for solo and family firms, playing an especially significant role for family firms. Furthermore, we found that household income is not a significant predictor of start-up activity completion for teams. Results from our study reinforce the extant literature on the benefits of starting a firm with teams, and suggests that these enterprise types may provide a more stable platform on which to launch a start-up. Implications of these findings and opportunities for future research are offered.

Many of today’s information and technology systems and environments facilitate inquiry, learning, consciousness-raising and knowledge-building. Such platforms include e-learning systems which have learning, education and/or training as explicit goals or objectives. They also include search engines, social media platforms, video-sharing platforms, and knowledge sharing environments deployed for work, leisure, inquiry, and personal and professional productivity. The new journal, Information and Learning Sciences, aims to advance our understanding of human inquiry, learning and knowledge-building across such information, e-learning, and socio-technical system contexts.

This article introduces the journal at its launch under new editorship in January, 2019. The article, authored by the journal co-editors and all associate editors, explores the lineage of scholarly undertakings that have contributed to the journal's new scope and mission, which includes past and ongoing scholarship in the following arenas: Digital Youth, Constructionism, Mutually Constitutive Ties in Information and Learning Sciences, and Searching-as-Learning.

The article offers examples of ways in which the two fields stand to enrich each other towards a greater holistic advancement of scholarship. The article also summarizes the inaugural special issue contents from the following contributors: Caroline Haythornthwaite; Krista Glazewski and Cindy Hmelo-Silver; Stephanie Teasley; Gary Marchionini; Caroline R. Pitt; Adam Bell, Rose Strickman and Katie Davis; Denise Agosto; Nicole Cooke; and Victor Lee.

The article, this special issue, and the journal in full, are among the first formal and ongoing publication outlets to deliberately draw together and facilitate cross-disciplinary scholarship at this integral nexus. We enthusiastically and warmly invite continued engagement along these lines in the journal’s pages, and also welcome related, and wholly contrary points of view, and points of departure that may build upon or debate some of the themes we raise in the introduction and special issue contents.

Incumbent retail organisations need to develop new capabilities to adapt with the increasingly competitive retail landscape. Despite the growing relevance of innovation in retail practice, the strategic management of innovation in retailing is still vastly under-researched. This explorative study thus aims to investigate how incumbent retail firms can organise for innovation from an organisational ambidexterity perspective.

A single-case study of an established Swedish retail firm was conducted from December 2016 to July 2018 and followed up in June 2021. The authors followed the process of implementation of organisational changes aimed to increase innovation in the company, particularly the introduction of a digital marketing initiative and a corporate innovation hub. Data collection was based on nine semi-structured interviews and participant observations and unstructured interviews from 13 meetings and workshops. An abductive approach to data analysis was followed, iteratively comparing theoretical concepts and empirical data using open, axial and selective coding to distil findings into aggregated themes.

Given the inherently limited formalisation of innovation processes in most retail organisations, structural ambidexterity appears to be necessary when the aim is radical, strategic retail innovation. Structural mechanisms are able to safeguard the space and resources to focus on long-term research and projects with higher risk and uncertainty; however, integration of innovation activities to the mainstream organisation is critical. Pursuing contextual ambidexterity, wherein instead of structural solutions, employees are empowered to divide employees' time between innovation-related and efficiency-related tasks, is more likely related to retail innovations that are incremental and operational.

The paper contributes to the emerging topic of strategic management of innovation in retailing, by explicating how incumbent retailers can organise for innovation depending on the type of innovation that is aimed for, using organisational ambidexterity as a novel perspective.