Development of Sorghum (Sorghum bicolor (L.) Moench) Endosperm in Varieties of Varying Hardness

Factors responsible for grain hardness in sorghum are not well understood. Therefore, a study was undertaken to observe differences in the developmental processes of three sorghum varieties which vary in endosperm texture: hard, intermediate, and soft. Grain samples were collected at 5 day intervals beginning at 5 days after half-bloom (DAHB) until physiological maturity (40 DAHB) and prepared for viewing with scanning electron microscopy and transmission electron microscopy. Comparisons were made between vitreous and floury endosperm portions of each variety and among the three varieties. The major difference between vitreous and floury endosperm was the degree to which the protein matrix was present and continuous. The protein matrix which surrounds the starch granules forms at approximately 20 DAHB. The proportion of cells in the endosperm with a continuous protein matrix corresponds to the proportion of vitreous endosperm in the mature kernel. A similar sequence of development was observed in the hard, intermediate, and soft varieties. however, the harder varieties appeared to develop faster than the softer varieties. Differences between hard and soft varieties were visible as early as 15 DAHB. In the early stages of endosperm development, the hard variety had a higher concentration of protein bodies in the outer endosperm than the softer varieties

Radial Photonic Crystal for detection of frequency and position of radiation sources

Based on the concepts of artificially microstructured materials, i.e. metamaterials, we present here the first practical realization of a radial wave crystal. This type of device was introduced as a theoretical proposal in the field of acoustics, and can be briefly defined as a structured medium with radial symmetry, where the constitutive parameters are invariant under radial geometrical translations. Our practical demonstration is realized in the electromagnetic microwave spectrum, because of the equivalence between the wave problems in both fields. A device has been designed, fabricated and experimentally characterized. It is able to perform beam shaping of punctual wave sources, and also to sense position and frequency of external radiators. Owing to the flexibility offered by the design concept, other possible applications are discussed.This work was supported in part by the Spanish Ministry of Science and Innovation under Grants TEC 2010-19751 and CSD2008-00066 (Consolider program) and by the U.S. Office of Naval Research under Grant N000140910554.Carbonell Olivares, J.; Díaz Rubio, A.; Torrent Martí, D.; Cervera Moreno, FS.; Kirleis, MA.; Pique, A.; Sánchez-Dehesa Moreno-Cid, J. (2012). Radial Photonic Crystal for detection of frequency and position of radiation sources. Scientific Reports. 2(558):1-8. https://doi.org/10.1038/srep00558S182558Pendry, J., Schurig, D. & Smith, D. Controlling electromagnetic fields. Science 312, 1780–1782 (2006).Leonhardt, U. Optical conformal mapping. Science 312, 1777–1780 (2006).Smith, D., Padilla, W., Vier, D., Nemat-Nasser, S. & Schultz, S. Composite medium with simultaneously negative permeability and permittivity. Phys. Rev. Lett. 84, 4184–4187 (2000).Pendry, J. B. Negative refraction makes a perfect lens. Phys. Rev. Lett. 85, 3966–3969 (2000).Schurig, D. et al. Metamaterial electromagnetic cloak at microwave frequencies. Science 314, 977–980 (2006).Narimanov, E. E. & Kildishev, A. V. Optical black hole: Broadband omnidirectional light absorber. Appl. Phys. Lett. 95, 041106 (2009).Grbic, A. & Eleftheriades, G. Overcoming the diffraction limit with a planar left-handed transmission-line lens. Phys. Rev. Lett. 92, 117403 (2004).Ma, H. F. & Cui, T. J. Three-dimensional broadband ground-plane cloak made of metamaterials. Nature Communications 1, 21 (2010).Engheta, N., Salandrino, A. & Alu, A. Circuit elements at optical frequencies: Nanoinductors, nanocapacitors and nanoresistors. Phys. Rev. Lett. 95, 095504 (2005).Zhang, F. et al. Negative-Zero-Positive Refractive Index in a Prism-Like Omega-Type Metamaterial. IEEE Trans. Microwave Theory Tech. 56, 2566–2573 (2008).Baena, J., Marques, R., Medina, F. & Martel, J. Artificial magnetic metamaterial design by using spiral resonators. Phys. Rev. B 69, 014402 (2004).Carbonell, J., Torrent, D., Diaz-Rubio, A. & Sanchez-Dehesa, J. Multidisciplinary approach to cylindrical anisotropic metamaterials. New J. Phys. 13, 103034 (2011).Torrent, D. & Sanchez-Dehesa, J. Radial Wave Crystals: Radially Periodic Structures from Anisotropic Metamaterials for Engineering Acoustic or Electromagnetic Waves. Phys. Rev. Lett. 103, 064301 (2009).Torrent, D. & Sanchez-Dehesa, J. Acoustic resonances in two-dimensional radial sonic crystal shells. New J. Phys. 12, 073034 (2010).Kurs, A. et al. Wireless power transfer via strongly coupled magnetic resonances. Science 317, 83–86 (2007).Marques, R., Medina, F. & Rafii-El-Idrissi, R. Role of bianisotropy in negative permeability and left-handed metamaterials. Phys. Rev. B 65, 144440 (2002).Pendry, J. B., Holden, A. J., Robbins, D. J. & Stewart, W. J. Magnetism from conductors and enhanced nonlinear phenomena. IEEE Trans. Microwave Theory Tech. 47, 2075–2084 (1999).Pollock, J. G. & Iyer, A. K. Effective-Medium Properties of Cylindrical Transmission-Line Metamaterials. IEEE Antennas and Wireless Propagation Letters 10, 1491–1494 (2011).Comsol, A. B. (Sweden). Comsol Multiphysics (v. 4.1). (2010).Ansoft. High Frequency Structure Simulator (HFSS), v.14. (2012).Smith, D. R., Vier, D. C., Koschny, T. & Soukoulis, C. M. Electromagnetic parameter retrieval from inhomogeneous metamaterials. Phys. Rev. E 71, 036617 (2005).Yang, Y. et al. Optofluidic waveguide as a transformation optics device for lightwave bending and manipulation. Nature Communications 3, 651 (2012).Liu, R. et al. Broadband Ground-Plane Cloak. Science 323, 366–369 (2009).Cheng, Q., Cui, T. J., Jiang, W. X. & Cai, B. G. An omnidirectional electromagnetic absorber made of metamaterials. New J. Phys. 12, 063006 (2010)

Isotopes prove advanced, integral crop production, and stockbreeding strategies nourished Trypillia mega-populations

After 500 y of colonizing the forest-steppe area northwest of the Black Sea, on the territories of what is today Moldova and Ukraine, Trypillia societies founded large, aggregated settlements from ca. 4150 BCE and mega-sites (>100 ha) from ca. 3950 BCE. Covering up to 320 ha and housing up to 15,000 inhabitants, the latter were the world’s largest settlements to date. Some 480 δ 13C and δ 15N measurements on bones of humans, animals, and charred crops allow the detection of spatio-temporal patterns and the calculation of complete agricultural Bayesian food webs for Trypillia societies. The isotope data come from settlements of the entire Trypillia area between the Prut and the Dnieper rivers. The datasets cover the development of the Trypillia societies from the early phase (4800–4200/4100 BCE), over the agglomeration of mega-sites (4200/4100–3650 BCE), to the dispersal phase (3650–3000 BCE). High δ 15N values mostly come from the mega-sites. Our analyses show that the subsistence of Trypillia mega-sites depended on pulses cultivated on strongly manured (dung-)soils and on cattle that were kept fenced on intensive pasture s to easy collect the manure for pulse cultivation. The food web models indicate a low proportion of meat in human diet (approximately 10%). The largely crop-based diet, consisting of cereals plus up to 46% pulses, was balanced in calories and indispensable amino acids. The flourishing of Europe’s first mega-populations depended on an advanced, integral mega-economy that included sophisticated dung management.Their demise was therefore not economically, but socially, conditioned [Hofmann et al., PLoS One. 14, e0222243 (2019)]

New AMS 14C dates track the arrival and spread of broomcorn millet cultivation and agricultural change in prehistoric Europe

Broomcorn millet (Panicum miliaceum L.) is not one of the founder crops domesticated in Southwest Asia in the early Holocene, but was domesticated in northeast China by 6000 bc. In Europe, millet was reported in Early Neolithic contexts formed by 6000 bc, but recent radiocarbon dating of a dozen 'early' grains cast doubt on these claims. Archaeobotanical evidence reveals that millet was common in Europe from the 2nd millennium bc, when major societal and economic transformations took place in the Bronze Age. We conducted an extensive programme of AMS-dating of charred broomcorn millet grains from 75 prehistoric sites in Europe. Our Bayesian model reveals that millet cultivation began in Europe at the earliest during the sixteenth century bc, and spread rapidly during the fifteenth/fourteenth centuries bc. Broomcorn millet succeeds in exceptionally wide range of growing conditions and completes its lifecycle in less than three summer months. Offering an additional harvest and thus surplus food/fodder, it likely was a transformative innovation in European prehistoric agriculture previously based mainly on (winter) cropping of wheat and barley. We provide a new, high-resolution chronological framework for this key agricultural development that likely contributed to far-reaching changes in lifestyle in late 2nd millennium bc Europe

Viking Age garden plants from southern Scandinavia: diversity, taphonomy and cultural aspects

Plant finds recovered from archaeological sites in southern Scandinavia dated to the Viking Age reflect the diversity of useful plants that were cultivated and collected. This review presents the results of 14 investigations of deposits that are dated between AD 775 and 1050. The site types are categorized as agrarian, urban, military and burials. Garden plants are unevenly distributed, as the greatest diversity is recorded in features from urban contexts. We argue that taphonomic processes played an important role in the picture displayed. Archaeobotanical research results from neighbouring regions suggest that Viking Age horticulture has its roots in older traditions, and that the spectrum of garden plants is influenced by central and north-western European horticultural customs, which were to a great extent shaped by Roman occupation

Triticum timopheevii s.l. (‘new glume wheat’) finds in regions of southern and eastern Europe across space and time

Triticum timopheevii sensu lato (‘new glume wheat’, NGW) was first recognised as a distinct prehistoric cereal crop through work on archaeobotanical finds from Neolithic and Bronze Age sites in northern Greece. This was later followed by its identification in archaeobotanical assemblages from other parts of Europe. This paper provides an overview of the currently known archaeobotanical finds of Timopheev’s wheat in southeastern and eastern Europe and observes their temporal span and spatial distribution. To date, there are 89 prehistoric sites with these finds, located in different parts of the study region and dated from the Neolithic to the very late Iron Age. Their latest recorded presence in the region is in the last centuries BCE. For assemblages from the site as a whole containing at least 30 grain and/or chaff remains of Timopheev’s wheat, we take a brief look at the overall relative proportions of Triticum monococcum (einkorn), T. dicoccum (emmer) and T. timopheevii s.l. (Timopheev’s wheat), the three most common glume wheats in our study region in prehistory. We highlight several sites where the overall proportions of Timopheev’s wheat might be taken to suggest it was a minor component of a mixed crop (maslin), or an unmonitored inclusion in einkorn or emmer fields. At the same sites, however, there are also discrete contexts where this wheat is strongly predominant, pointing to its cultivation as a pure crop. We therefore emphasise the need to evaluate the relative representation of Timopheev’s wheat at the level of individual samples or contexts before making inferences on its cultivation status. We also encourage re-examination of prehistoric and historic cereal assemblages for its remains