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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.

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.

The purpose of this paper is to examine the influence of cultural leadership factors (charismatic/value-based, team oriented, participative, humane, autonomous and self-protective) on the rates of opportunity and necessity entrepreneurship.

The study integrates insights from institutional and cultural leadership theories to provide a fresh perspective to advance comparative entrepreneurship research. To test the hypotheses, the authors conduct a multiple regression analysis with observations from 34 countries, using data (from the year 2013) from the Global Entrepreneurship Monitor for the dependent variable and from Global Leadership and Organizational Behavior Effectiveness to create leadership factors as independent variables.

The results show that all the types of leadership considered in the study have a relevant effect on entrepreneurial activity. However, charismatic leadership has a greater effect on entrepreneurial activity, particularly on opportunity entrepreneurship. The research also shows that autonomous leadership has a negative impact on entrepreneurial activity, although, when it is moderated by the humane dimension, this relationship changes.

Since the alternative dimensions facilitate or inhibit the generation of new firm creation, it is critical for researchers, teachers and leaders to learn about and to foster such leadership types.

This research covers a gap in the cross-cultural evidence presented in the literature and suggests the integration of the concepts leadership and entrepreneurship.

The purpose of this paper was to study the genetic variability, heritability, heat tolerance indices and phenotypic and genotypic correlation studies for traits of 250 elite International Center for Agricultural Research in the Dry Areas (ICARDA) bread wheat genotypes under high temperature in Wad Medani, Center in Sudan.

Bread wheat is an important food on a global level and is used in the form of different products. High temperature associated with climate change is considered to be a detrimental stress in the future on world wheat production. A total of 10,250 bread wheat genotypes selected from different advanced yield trials introduction from ICARDA and three checks including were grown in two sowing dates (SODs) (1st and 2nd) 1st SOD heat stress and 2nd SOD non-stress at the Gezira Research Farm, of the Agricultural Research Corporation, Wad Medani, Sudan.

An alpha lattice design with two replications was used to assess the presence of phenotypic and genotypic variations of different traits, indices for heat stress and heat tolerance for 20 top genotypes and phenotypic and genotypic correlations. Analysis of variance revealed significant differences among genotypes for all the characters. A wide range, 944-4,016 kg/ha in the first SOD and 1,192-5,120 kg/ha in the second SOD, was found in grain yield. The average yield on the first SOD is less than that of the secondnd SOD by 717.7 kg/ha, as the maximum and minimum temperatures were reduced by 3ºC each in the second SOD when compared to the first SOD of the critical stage of crop growth shown.

Similar wide ranges were found in all morpho-physiological traits studied. High heritability in a broad sense was estimated for days to heading and maturity. Moderate heritability estimates found for grain yield ranged from 44 to 63.6 per cent, biomass ranged from 37.8 to 49.1 per cent and canopy temperature (CT) after heading ranged from 44.2 to 48 per cent for the first and secondnd SODs. The top 20 genotypes are better than the better check in the two sowing dates and seven genotypes (248, 139, 143, 27, 67, 192 and 152) were produced high grain yield under both 1st SOD and 2nd SOD.

The same genotypes in addition to Imam (check) showed smaller tolerance (TOL) values, indicating that these genotypes had a smaller yield reduction under heat-stressed conditions and that they showed a higher heat stress susceptibility index (SSI). A smaller TOL and a higher SSI are favored. Both phenotypic and genotypic correlations of grain yield were positively and significantly correlated with biomass, harvest index, number of spikes/m², number of seeds/spike and days to heading and maturity in both SODs and negatively and significantly correlated with canopy temperature before and after heading in both SODs.

Genetic variations, heritability, heat tolerance indices and correlation studies for traits of bread wheat genotypes under high temperature

This paper aims to inform the promotion of sustainable modes of transport. For this purpose, it deploys a means-ends framework as a type of second-order cybernetics and uses it to explore cognitive transport mode choice structures.

The empirical study relies on a purposive sample and a qualitative research methodology known as laddering. It is aimed at the identification and comparative analysis of the cognitive means-ends structures of transport users.

The results reveal more positive and complex associations for the car than for public transport. Two main positive means-ends structures are identified for public transport, one related with the relaxation and the other with doing useful things while travelling. Dominant positive structures for the car are related with self-confidence, satisfaction and personal freedom. Negative means-ends structures in addition reveal important justifications and rationalizations for car use.

Based on the identified distinct means-ends elements and structures, this study holds important implications for developing a communications strategy and policy interventions seeking to promote public transport.

Means-ends theory is proposed as an integrative cybernetic framework for the study of stakeholders’ (customers’) mental models. The empirical study is the first to concurrently and comparatively examine positive and negative means-ends chains for the car and for the public transport modes.

The purpose of this paper is to introduce an approach in measuring the shielding gas flow within laser powder bed fusion (L-PBF) machines under near-process conditions (regarding oxygen content and shielding gas flow).

The measurements are made sequentially using a hot-wire anemometer. After a short introduction into the measurement technique, the system which places the measurement probe within the machine is described. Finally, the measured shielding gas flow of a commercial L-PBF machine is presented.

An approach to measure the shielding gas flow within SLM machines has been developed and successfully tested. The use of a thermal anemometer along with an automated probe-placement system enables the space-resolved measurement of the flow speed and its turbulence.

The used single-normal (SN) hot-wire anemometer does not provide the flow vectors’ orientation. Using a probe with two or three hot-films and an improved placement system will provide more information about the flow and less disturbance to it.

A measurement system which allows the measurement of the shielding gas flow within commercial L-PBF machines is presented. This enables the correlation of the shielding gas flow with the resulting parts’ quality.