Copy Number Variation Affecting the Photoperiod-B1 and Vernalization-A1 Genes Is Associated with Altered Flowering Time in Wheat (Triticum aestivum)

The timing of flowering during the year is an important adaptive character affecting reproductive success in plants and is critical to crop yield. Flowering time has been extensively manipulated in crops such as wheat (Triticum aestivum L.) during domestication, and this enables them to grow productively in a wide range of environments. Several major genes controlling flowering time have been identified in wheat with mutant alleles having sequence changes such as insertions, deletions or point mutations. We investigated genetic variants in commercial varieties of wheat that regulate flowering by altering photoperiod response (Ppd-B1 alleles) or vernalization requirement (Vrn-A1 alleles) and for which no candidate mutation was found within the gene sequence. Genetic and genomic approaches showed that in both cases alleles conferring altered flowering time had an increased copy number of the gene and altered gene expression. Alleles with an increased copy number of Ppd-B1 confer an early flowering day neutral phenotype and have arisen independently at least twice. Plants with an increased copy number of Vrn-A1 have an increased requirement for vernalization so that longer periods of cold are required to potentiate flowering. The results suggest that copy number variation (CNV) plays a significant role in wheat adaptation

Identification of a Lacosamide Binding Protein Using an Affinity Bait and Chemical Reporter Strategy: 14-3-3 ζ

We have advanced a useful strategy to elucidate binding partners of ligands (drugs) with modest binding affinity. Key to this strategy is attaching to the ligand an affinity bait (AB) and a chemical reporter (CR) group, where the AB irreversibly attaches the ligand to the receptor upon binding and the CR group is employed for receptor detection and isolation. We have tested this AB&CR strategy using lacosamide ((R)-1), a low-molecular-weight antiepileptic drug. We demonstrate that using a (R)-lacosamide AB&CR agent ((R)-2) 14-3-3 ζ in rodent brain soluble lysates is preferentially adducted, adduction is stereospecific with respect to the AB&CR agent, and adduction depends upon the presence of endogenous levels of the small molecule metabolite xanthine. Substitution of lacosamide AB agent ((R)- 5) for (R)-2 led to the identification of the 14-3-3 ζ adduction site (K120) by mass spectrometry. Competition experiments using increasing amounts of (R)-1 in the presence of (R)-2 demonstrated that (R)-1 binds at or near the (R)-2 modification site on 14-3-3 ζ. Structure-activity studies of xanthine derivatives provided information concerning the likely binding interaction between this metabolite and recombinant 14-3-3 ζ. Documentation of the 14-3-3 ζ-xanthine interaction was obtained with isothermal calorimetry using xanthine and the xanthine analogue 1,7-dimethylxanthine

Conventional and Molecular Breeding Approaches for Biofortification of Pearl Millet

Pearl millet [Pennisetum glaucum (L.) R. Br.] is an essential diet of more than 90 million people in the semi-arid tropics of the world where droughts and low fertility of soils cause frequent failures of other crops. It is an important nutri-rich grain cereal in the drier regions of the world grown on 26 mha by millions of farmers (IFAD 1999; Yadav and Rai 2013). This makes pearl millet the sixth most important crop in the world and fourth most important food crop of the India, next to rice, wheat, and maize with annual cultivation over an area of ~8 mha. Pearl millet is also primary food crop in sub-Saharan Africa and is grown on 15 mha (Yadav and Rai 2013). The significant increase in productivity of pearl millet in India is attributed to development and adoption of hybrids of early to medium duration maturity. More than 120 diverse hybrids/varieties have been released till date for various production environments. The heterosis breeding and improved crop management technologies increased productivity substantially achieving higher increased production of 9.80 mt in 2016–2017 from 2.60 mt in 1950–1951 in spite of declined of area under the crop by 20–30% over last two decades (Yadav et al. 2012)

Entry, descent and landing systems analysis of Mars exploration missions.

Planetary exploration has always been a very complex and risky engineering problem. Building on the past successes, more missions are currently being considered and investigated for the near future. One of the cornerstones of a successful lander-based planetary mission is the Entry, Descent and Landing System (EDLS) on which this work concentrates. The Entry, Descent and Landing sequence is introduced in the broader context of planetary exploration and the various systems involved in delivering safely a payload on the surface are presented. The literature review concentrates on a number of studies that emphasised the need to understand the whole EDL sequence to help designing better systems. It also introduces the reader to the current state-of-the-art both in term of EDLS technologies and design methods as well as identifying a need to design EDL systems in a more integrated and streamlined manner. From the conclusions of the literature review, the main drivers of the EDLS are identified and a new integrated computational framework, SPADES, is developed that provides analysis and design of entry systems. Current and new methods are built into the framework to size all the main EDL systems and provide realistic simulated scenario validated against past missions data. From this point onward, new mission data is generated in the form of the proposed 140 kg astrobiology-focused Vanguard Mars Mission, for which both a parachute and an inflatable-based EDLS is produced. In addition, an ESA mars lander concept is investigated, focusing on the scalability of powered landing systems up to the scale of the future Mars Sample Return vehicle. Finally, building on the case studies and additional mission scenarios, the influence of spatial and atmospheric variables on the performance of EDLS is systematically assessed to provide planet- wide access maps for specific EDL systems and characterise the impact of low-density atmospheric profiles on a number of mission parameters

Entry, descent and landing systems analysis of Mars exploration missions

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Evolving legged robots using biologically inspired optimization strategies

When designing a legged robot a small change in one variable can have a significant effect on a number of the robot’s characteristics, meaning that making tradeoffs can be difficult. The algorithm presented in this paper uses biologically inspired optimization techniques to identify the effects of changing various robot design variables and determine if there are any general rules which can be applied to the design of a legged robot. Designs produced by this simulation are also compared to existing robot designs and biological systems, showing that the algorithm produces results which require less power than other robots of a similar mass, and which share a number of characteristics with biological systems