Transcriptome Analysis of the Vernalization Response in Barley (Hordeum vulgare) Seedlings

Temperate cereals, such as wheat (Triticum spp.) and barley (Hordeum vulgare), respond to prolonged cold by becoming more tolerant of freezing (cold acclimation) and by becoming competent to flower (vernalization). These responses occur concomitantly during winter, but vernalization continues to influence development during spring. Previous studies identified VERNALIZATION1 (VRN1) as a master regulator of the vernalization response in cereals. The extent to which other genes contribute to this process is unclear. In this study the Barley1 Affymetrix chip was used to assay gene expression in barley seedlings during short or prolonged cold treatment. Gene expression was also assayed in the leaves of plants after prolonged cold treatment, in order to identify genes that show lasting responses to prolonged cold, which might contribute to vernalization-induced flowering. Many genes showed altered expression in response to short or prolonged cold treatment, but these responses differed markedly. A limited number of genes showed lasting responses to prolonged cold treatment. These include genes known to be regulated by vernalization, such as VRN1 and ODDSOC2, and also contigs encoding a calcium binding protein, 23-KD jasmonate induced proteins, an RNase S-like protein, a PR17d secretory protein and a serine acetyltransferase. Some contigs that were up-regulated by short term cold also showed lasting changes in expression after prolonged cold treatment. These include COLD REGULATED 14B (COR14B) and the barley homologue of WHEAT COLD SPECIFIC 19 (WSC19), which were expressed at elevated levels after prolonged cold. Conversely, two C-REPEAT BINDING FACTOR (CBF) genes showed reduced expression after prolonged cold. Overall, these data show that a limited number of barley genes exhibit lasting changes in expression after prolonged cold treatment, highlighting the central role of VRN1 in the vernalization response in cereals

Isotopic techniques to measure N2O, N2 and their sources

GHG emissions are usually the result of several simultaneous processes. Furthermore, some gases such as N2 are very difficult to quantify and require special techniques. Therefore, in this chapter, the focus is on stable isotope methods. Both natural abundance techniques and enrichment techniques are used. Especially in the last decade, a number of methodological advances have been made. Thus, this chapter provides an overview and description of a number of current state-of-theart techniques, especially techniques using the stable isotope 15N. Basic principles and recent advances of the 15N gas flux method are presented to quantify N2 fluxes, but also the latest isotopologue and isotopomer methods to identify pathways for N2O production. The second part of the chapter is devoted to 15N tracing techniques, the theoretical background and recent methodological advances. A range of different methods is presented from analytical to numerical tools to identify and quantify pathway-specific N2O emissions. While this chapter is chiefly concerned with gaseous N emissions, a lot of the techniques can also be applied to other gases such as methane (CH4), as outlined in Sect. 5.3

Recycled Polystyrene Waste to Triboelectric Nanogenerators: Volumetric Electromechanically Responsive Laminates from Same-Material Contact Electrification

Millions of tonnes of polystyrene (PS) are produced annually, with only an estimated 12% being recycled. Herein, the upcycling of expanded or foamed PS waste into electromechanically responsive triboelectric laminates (TLs) is described. These TLs possess internal triboelectric dipoles offering an alternative to ferroelectric fluoropolymers, and, when manufactured into triboelectric nanogenerators (TENGs), are able to generate over 200 V and 12 μA from motion. This energy harvesting is enabled by electrospinning alternating layers of small and large diameter PS fibers, which upon friction establish an effective dipole moment within the TL. The PS‐TENG shows remarkable stability and is able to charge a 0.47 μF capacitor to 15 V in 200 s of vibration from same material contact electrification, with piezoelectric contact‐mode testing showing that a single PS laminate is comparable to state‐of‐the‐art piezoelectric fluoropolymers for overall electromechanical conversion

Electrocatalysis for Green(er) Chemistry: Limitations and Opportunities with Traditional and Emerging Characterization Methods for Tangible Societal Impact

The world is facing grand challenges in energy security, environmental pollution, and sustainable use (and re‐use) of resources. Electrochemical processes, incorporating electrosynthesis, electrochemical catalysis, and electrochemical energy storage devices, provide pathways to address these challenges via green chemistry. However, the applicability of electrochemical processes for these systems is limited by the required energy input, the “electrons” in electrochemistry. Electrocatalysis as a subset of electrochemistry is set to underpin many of the United Nations Sustainable Development Goals, including “Affordable and Clean Energy” through the production of future fuels and abatement of carbon emissions; “Responsible Consumption and Production” through recycling and degradation of waste; and “Climate Action” through CO2 (and other greenhouse gas) remediation. The rise of green photovoltaic power has lowered the carbon cost of these electrons, making electrocatalysis an even more viable, green(er), chemical conversion pathway. This perspective highlights the need for comprehensive understanding of catalyst structure via in situ and operando analysis to complement device design considerations. The challenges faced by the field of electrocatalysis in data reporting, elimination of electrochemical artifacts, catalyst stability, and scaling to industrial relevance, along with opportunities, emerging tools, are discussed with a view to achieve the maximum ‘potential’ of electrocatalysis

Runa dla kompozytów z elektroprzędzonych nanowłókien z PVA i celulozy

A study of the manufacturing and characterisation of poly (vinyl alcohol) (PVA) nanofibre mats reinforced with microcrystalline cellulose (MCC) is presented. Results obtained from Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectrometry and Scanning Electron Microscopy (SEM) of the products are discussed and interpreted. PVA nano-fibre mats reinforced with MCC nano-whiskers (CNWs) were prepared from aqueous PVA solutions by NanospiderTM high-voltage electro-spinning on NS Lab 200 (Elmarco) equipment with a circular cylinder as the emitting electrode. PVA/CNWs mats of a modal nano-fibre diameter of 300 nm and average diameter within the range from 350 to 294 nm were obtained by the electro-spinning technique. Solution parameters, such as the content of CNWs in the solution and PVA concentration and viscosity were varied in an attempt to produce possibly finer cellulose nano-fibres.Przedstawiono badania dotyczące wytwarzania i charakterystyki nanowłókien z PVA wzmocnionych mikrokrystaliczną celulozą. Włókna otrzymywano za pomocą elektroprzędzenia przy zastosowaniu urządzenia Nanospider i formowania runa. Włókna badano za pomocą spektroskopii ATR-FTIR i elektromikroskopii skaningowej SEM. Uzyskano włókna o modalnej średnicy 300 nm i średniej w zakresie 294-350 nm. W celu uzyskania możliwie najcieńszych włókien stosowano rożne warunki przędzenia i stężenia roztworu przędzalniczego

Measuring Piezoelectric Output—Fact or Friction?

Piezoelectric polymers are emerging as exceptionally promising materials for energy harvesting. While the theoretical figures of merit for piezoelectric polymers are comparable to ceramics, the measurement techniques need to be retrofitted to account for the different mechanical properties of the softer polymeric materials. Here, how contact electrification, including friction and contact separation, is often mistaken for piezoelectric charge is examined, and a perspective for how to separate these effects is provided. The state of the literature is assessed, and recommendations are made for clear and simple guidelines in reporting, for both sample geometry and testing methods, to enable accurate determination of piezoelectric figures of merit in polymers. Such improvements will allow an understanding of what types of material manipulation are required in order to enhance the piezoelectric output from polymers and enable the next generation of polymer energy harvester design

Stronger Reductive Environment in Solvothermal Synthesis Leads to Improved Ga Doping Efficiency in ZnO Nanocrystals and Enhanced Plasmonic Absorption

The key parameter for degenerated semiconductor oxide plasmonic nanocrystals is the doping level. Hydrothermal and solvothermal approaches are considered to be less effective toward achieving high concentration of aliovalent donor dopants in a host oxide when compared to other synthesis methods that use long chain hydrocarbon solvents, fatty acids, and fatty amines as precursors. Because of this, although they have several advantages such as sustainability, ease of use, relatively inexpensive reagents and apparatus, and reduced environmental impact, they are excluded from the list of potential synthesis methods. Herein, an effective Zn2+ substitution with aliovalent Ga3+ in the ZnO host lattice is demonstrated, and it is achieved by increasing the reductive power of the solvothermal synthesis conditions by either solvent substitution or the addition of reducing agents. This increase results in an increased oxidation affinity of the medium. This in turn promotes Ga3+ incorporation into the ZnO lattice, by skewing the reaction equilibrium toward oxygen evolution