Pressure-induced changes of the vibrational modes of spin-crossover complexes studied by nuclear resonance scattering of synchrotron radiation

Nuclear inelastic scattering (NIS) spectra were recorded for the spin-crossover complexes STP and ETP (STP = [Fe(1,1,1-trisf[N-(2-pyridylmethyl)-N-methylamino]methylg- ethane)](ClO4)2 and ETP = [Fe(1,1,1-trisf[N-(2-pyridylmethyl)-N-methylamino]methylg-butane)](ClO4)2) at 30 K and at room temperature and also at ambient pressure and applied pressure (up to 2.6 GPa). Spin transition from the high-spin (HS) to the low-spin (LS) state was observed by lowering temperature and also by applying pressure at room temperature and has been assigned to the hardening of iron-bond stretching modes due to the smaller volume in the LS isomer

G03-1504 Lime Use for Soil Acidity Management

Soil acidity can reduce crop production by directly affecting roots and changing the availability of essential nutrients and toxic elements. Liming can neutralize soil acidity, but several factors can affect the economic benefits of liming. With continuous cropping, soil pH can decrease (i.e., increase in acidity) because of various factors, including crop removal and leaching of basic cations, application of ammoniabased nitrogen fertilizers, and organic matter decomposition. Adding lime or other materials can raise soil pH to the ideal range for crop production, create an environment for a healthy function of microbes, and increase the levels of calcium or magnesium ions

Increasing the Profitability of Fertilizer by Financed-Constrained Smallholder Farmers in Sub-Saharan Africa

Low commercial fertilizer use by smallholder farmers in developing regions of the world commonly limits productivity. Many of these farmers do not have the financial capacity to purchase enough fertilizer to maximize net returns on their limited investment per hectare. High fertilizer costs and low commodity prices often reduce profit potential, and competing needs for money often take priority. Such farmers need high net returns on their investments to justify the application of fertilizers

Interplay between Superconductivity and Magnetism in Rb0.8Fe1.6Se2 under Pressure

High-pressure magnetization, structural and 57Fe M\"ossbauer studies were performed on superconducting Rb0.8Fe1.6Se2.0 with Tc = 32.4 K. The superconducting transition temperature gradually decreases on increasing pressure up to 5.0 GPa followed by a marked step-like suppression of superconductivity near 6 GPa. No structural phase transition in the Fe vacancy-ordered superstructure is observed in synchrotron XRD studies up to 15.6 GPa, while the M\"ossbauer spectra above 5 GPa reveal the appearance of a new paramagnetic phase and significant changes in the magnetic and electronic properties of the dominant antiferromagnetic phase, coinciding with the disappearance of superconductivity. These findings underline the strong correlation between antiferromagnetic order and superconductivity in phase-separated AxFe2-x/2Se2 (A = K, Rb, Cs) superconductors

Density of Phonon States in Superconducting FeSe as a Function of Temperature and Pressure

The temperature and pressure dependence of the partial density of phonon states of iron atoms in superconducting Fe1.01Se was studied by 57Fe nuclear inelastic scattering (NIS). The high energy resolution allows for a detailed observation of spectral properties. A sharpening of the optical phonon modes and shift of all spectral features towards higher energies by ~4% with decreasing temperature from 296 K to 10 K was found. However, no detectable change at the tetragonal - orthorhombic phase transition around 100 K was observed. Application of a pressure of 6.7 GPa, connected with an increase of the superconducting temperature from 8 K to 34 K, results in an increase of the optical phonon mode energies at 296 K by ~12%, and an even more pronounced increase for the lowest-lying transversal acoustic mode. Despite these strong pressure-induced modifications of the phonon-DOS we conclude that the pronounced increase of Tc in Fe1.01Se with pressure cannot be described in the framework of classical electron-phonon coupling. This result suggests the importance of spin fluctuations to the observed superconductivity

Engineering a ROVER language in GEMOC STUDIO & MONTICORE: A comparison of language reuse support

Domain-specific languages (DSLs) improve engineering productivity through powerful abstractions and automation. To support the development of DSLs, the software language engineering (SLE) community has produced various solutions for the systematic engineering of DSLs that manifest in language workbenches. In this paper, we investigate the applicability of the language workbenches GEMOC STUDIO and MONTICORE to the MDETools’17 ROVER challenge. To this effect, we refine the challenge’s requirements and show how GEMOC STUDIO and MONTICORE can be leveraged to engineer a Rover-specific DSL by reusing existing DSLs and tooling of GEMOC STUDIO and MONTICORE. Through this, we reflect on the SLE state of the art, detail capabilities of the two workbenches focusing particularly on language reuse support, and sketch how modelers can approach ROVER programming with modern modeling tools

Intercalation effect on hyperfine parameters of Fe in FeSe superconductor with Tc = 42 K

57Fe-Mossbauer spectra of superconducting beta-FeSe, the Li/NH3 intercalate product and a subsequent sample of this intercalate treated with moist He gas have been measured in temperature range 4.7 - 290 K. A correlation is established between hyperfine parameters and critical temperature Tc in these phases. A strong increase of isomer shift upon intercalation is explained by a charge transfer from the Li/NH3 intercalate to the FeSe layers resulting in an increase of Tc up to 42 K. A significant decrease of the quadrupole splitting above 240 K has been attributed to diffusive motion of Li+ ions within the interlamellar space.Comment: 6 pages, 5 figures, 1 tabl

Atlas of common bean (Phaseolus vulgaris L.) production in Africa

The Bean atlas is a comprehensive map of the bean growing areas in Africa. The first version was first published in 1998 and in paper format. For the last four years, PABRA has been developing the second edition, which shows dramatic changes in bean production areas across Africa, where some have expanded and others have shifted. The new atlas will be digital and available online soon. The new edition contains information from bean producing areas in Eastern, Southern and Western Africa and represents a total of 22 countries. It overlays bean producing areas with information on: bean varieties grown in those regions; ongoing seed production and dissemination work; local, national and international bean markets; market routes; information on end users, farmers and bean consumption; bean constraints, both Biotic and abiotic; and more

Localized inhibition of protein phosphatase 1 by NUAK1 promotes spliceosome activity and reveals a MYC-sensitive feedback control of transcription.

Deregulated expression of MYC induces a dependence on the NUAK1 kinase, but the molecular mechanisms underlying this dependence have not been fully clarified. Here, we show that NUAK1 is a predominantly nuclear protein that associates with a network of nuclear protein phosphatase 1 (PP1) interactors and that PNUTS, a nuclear regulatory subunit of PP1, is phosphorylated by NUAK1. Both NUAK1 and PNUTS associate with the splicing machinery. Inhibition of NUAK1 abolishes chromatin association of PNUTS, reduces spliceosome activity, and suppresses nascent RNA synthesis. Activation of MYC does not bypass the requirement for NUAK1 for spliceosome activity but significantly attenuates transcription inhibition. Consequently, NUAK1 inhibition in MYC-transformed cells induces global accumulation of RNAPII both at the pause site and at the first exon-intron boundary but does not increase mRNA synthesis. We suggest that NUAK1 inhibition in the presence of deregulated MYC traps non-productive RNAPII because of the absence of correctly assembled spliceosomes