The revolutionary technology of CRISPR/Cas systems and their extraordinary potential to address fundamental questions in every field of biological sciences has led to their developers being awarded the 2020 Nobel Prize for Chemistry. In agriculture, CRISPR/Cas systems have accelerated the development of new crop varieties with improved traits—without the need for transgenes. However, the future of this technology depends on a clear and truly global regulatory framework being developed for these crops. Some CRISPR-edited crops are already on the market, and yet countries and regions are still divided over their legal status. CRISPR editing does not require transgenes, making CRISPR crops more socially acceptable than genetically modified crops, but there is vigorous debate over how to regulate these crops and what precautionary measures are required before they appear on the market. This article reviews intended outcomes and risks arising from the site-directed nuclease CRISPR systems used to improve agricultural crop plant genomes. It examines how various CRISPR system components, and potential concerns associated with CRISPR/Cas, may trigger regulatory oversight of CRISPR-edited crops. The article highlights differences and similarities between GMOs and CRISPR-edited crops, and discusses social and ethical concerns. It outlines the regulatory framework for GMO crops, which many countries also apply to CRISPR-edited crops, and the global regulatory landscape for CRISPR-edited crops. The article concludes with future prospects for CRISPR-edited crops and their products.

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This study investigates the effects of sinusoidal pulsations externally imposed to an oblique round jet. The effectiveness of film coverage of an adiabatic wall onset for a thermally uniform bulk flow is presented in the perspective of gas turbine film cooling. For the injectant fluid, both the temperature and the mass flow rate are controlled prior to entrance to the periodic forcing system using a loudspeaker drive. The characteristic film cooling parameters including the blowing ratios and the temperature ratio are maintained at M=ρiUi/ρ∞U∞ = 0.65, 1, and 1.25, and Ti/T∞=2 respectively. The injection fluid is pulsated to a nondimensionalized frequency of St=f⋅d/U = 0, 0.2, 0.3, and 0.5. In the present investigation, the impact of injectant film modulation is figured out by analyzing the velocity fields measured by a system of time-resolved particle image velocimetry (TR-PIV), as well as analyzing the adiabatic wall temperature and the convective heat transfer coefficient measured by a system of infrared thermography. The overall film-cooling effectiveness is revealed by the time-averaged analysis, in which altered time-averaged jet trajectories and wake behavior are focused. It is observed that the pulsations tend to result in lower effectiveness when the flow remained attached to the wall in steady blowing case. In steady blowing cases with jet liftoff, such as for M= 1.25, rendering low-frequency pulsation helps in increasing film-cooling effectiveness due to the discharge of lower mass flow rate coolant during the significant time interval of the respective pulse cycle.

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