An explanation of anomalous non-Hookean deformation of ionic single crystals

Anomalous non-Hookean deformation of ionic single crystal

Inhibition in the dynamics of selective attention: an integrative model for negative priming

We introduce a computational model of the negative priming (NP) effect that includes perception, memory, attention, decision making, and action. The model is designed to provide a coherent picture across competing theories of NP. The model is formulated in terms of abstract dynamics for the activations of features, their binding into object entities, their semantic categorization as well as related memories and appropriate reactions. The dynamic variables interact in a connectionist network which is shown to be adaptable to a variety of experimental paradigms. We find that selective attention can be modeled by means of inhibitory processes and by a threshold dynamics. From the necessity of quantifying the experimental paradigms, we conclude that the specificity of the experimental paradigm must be taken into account when predicting the nature of the NP effect

Bauernhofeffekt und Bio-Milchkonsum vor dem Hintergrund des Grundprinzips Gesundheit in der Ökologischen Landwirtschaft

The farm effect, reported in more than 40 studies, is associated with the more wellknown hygiene hypothesis. In particular the early consumption of untreated milk in a human's life may, besides genetic predisposition, impact the immune system of children and may prevent atopic diseases in their whole lifespan. Due to the special role of untreated milk, the question was answered, which milk causes a remarkable farm effect. There is evidence for differences between effects of treatment degrees of milk as well as its organic and conventional origin. These findings were evaluated before the background of organic agriculture by comprehensively reviewing existing interdisciplinary literature including medicinal studies and by conducting an expert interview. In consequence traditional lifestyle habits such as farm visits by children and organic milk consumption should be implemented in future preventive approaches, particularly because health has always been eminent in the principles of the organic agricultural movement

Profitability and risk evaluation of novel perennial pasture systems for livestock producers in the high rainfall zone: Context, Approach and Preliminary Results

The decision to invest in pasture improvement raises various questions for the livestock grazier, with the most pertinent being about the potential returns and risks. In the high rainfall zone of south-west Victoria, researchers have trialled novel perennial pasture systems with the aim of substantially increasing on-farm profits whilst simultaneously improving environmental outcomes. Results from the Hamilton EverGraze® proof site have shown potential to greatly improve livestock production. Promotion of the pasture technology is the next step. Key to this process is developing information about profitability and risk regarding the decision to invest in the new pasture. To help meet this need a model of a representative mixed livestock farm system for the region has been developed to generate information about profit, cash wealth and risk to aid extension and help inform decisions. The farm is comprised of a wool and meat producing sheep system and a beef enterprise. Using the model, the performance of two of the novel pasture systems can be evaluated against current practice, and compared to determine which of the two is the most beneficial EverGraze® option for the future. The risk associated with the pasture decision is assessed by considering different price structures and seasonal outcomes, and evaluating these effects on net benefits. Discounted cash flows, net present values and internal rates of return are estimated for the alternative systems, which include the effects of this price and seasonal variability. Preliminary results have been calculated, however further work is needed to confirm these. The method and results of the analysis provide information that is valuable for farm decisions about investing in a new pasture system and provide a basis for future economic analyses at the case study site and elsewhere.Farm Management,

The life cycle of starbursting circumnuclear gas discs

High-resolution observations from the sub-mm to the optical wavelength regime resolve the central few 100pc region of nearby galaxies in great detail. They reveal a large diversity of features: thick gas and stellar discs, nuclear starbursts, in- and outflows, central activity, jet interaction, etc. Concentrating on the role circumnuclear discs play in the life cycles of galactic nuclei, we employ 3D adaptive mesh refinement hydrodynamical simulations with the RAMSES code to self-consistently trace the evolution from a quasi-stable gas disc, undergoing gravitational (Toomre) instability, the formation of clumps and stars and the disc's subsequent, partial dispersal via stellar feedback. Our approach builds upon the observational finding that many nearby Seyfert galaxies have undergone intense nuclear starbursts in their recent past and in many nearby sources star formation is concentrated in a handful of clumps on a few 100pc distant from the galactic centre. We show that such observations can be understood as the result of gravitational instabilities in dense circumnuclear discs. By comparing these simulations to available integral field unit observations of a sample of nearby galactic nuclei, we find consistent gas and stellar masses, kinematics, star formation and outflow properties. Important ingredients in the simulations are the self-consistent treatment of star formation and the dynamical evolution of the stellar distribution as well as the modelling of a delay time distribution for the supernova feedback. The knowledge of the resulting simulated density structure and kinematics on pc scale is vital for understanding inflow and feedback processes towards galactic scales.Comment: accepted by MNRA

Nutrient Balances of Rewetted Fens – Groundwater Lysimeter Results

With the raising of groundwater levels to protect fens and the climate, there may be a risk of nutrients, such as nitrogen or potassium, leaching into the groundwater. Great amounts of nutrients, which are accumulated largely by peat forming plants like Phragmites australis and Carex spec., are conveyed into rewetted fens through high amounts of introduced water. Nitrogen leaching into the groundwater is very low even at the beginning of flooding and there is no sudden, pronounced leaching. Only a portion of potassium is taken up by plants whereas the rest might be found in the groundwater. Increasing nutrient inputs must be expected as soon as more contaminated water is added contributing to the regeneration of groundwater and increasing the pollution with nutrients at once

Experimental analysis of the Fitzgerald apparatus

Experimental analysis of Fitzgerald dynamic compliance machin

Use of polymeric supports for the synthesis of structurally defined oligomers.

The aims of this project were firstly to develop a protocol for the iterative synthesis of polyethers on a polymeric support, using suitably protected monomers. The synthesis of cyclic ethers by an intramolecular cyclisation/cleavage from the polymeric support, utilising a sulfonyl chloride linker, was also desired. The final aim was to develop a method for reductive amination on a polymeric support, with a view to forming mixed amine/ether oligomers. Chapter 1 is a review of the range of polymers that have been used as supports in organic synthesis, various linkers that have been used to immobilise molecules onto supports, the synthesis of polyethers and cyclic ethers in solution and on polymeric supports, and reductive amination in solution and on polymeric supports. Chapter 2 describes the protecting group strategies that were developed for the synthesis of linear, singly branched and dibranched monomers. These strategies gave monomers in very high yields, which were suitably protected for use in the synthesis of oligomers and cyclic ethers in later chapters. Chapter 3 describes the synthesis of novel linkers on a soluble PEG support PEG sulfonyl chloride and PEG Wang trichloroacetimidate. Both linkers were synthesised in high yields, and were successfully utilised in the PEG supported reactions described in later chapters. Chapter 4 describes the synthesis of oxetanes by mono-activation of a branched diol as a sulfonate ester in solution, on cross-linked polystyrene and on PEG, followed by intramolecular cyclisation/cleavage. Oxetanes were afforded in good yields, under mild conditions, with rapid purification. Chapter 5 describes the development of an iterative polyether synthesis, initially on cross-linked polystyrene, and then on a PEG support. This provided access to a range of structurally defined oligoethers and avoided the laborious purification techniques associated with classical solution based methods. Chapter 6 describes the mild and selective oxidation of an immobilised alcohol to an aldehyde on a PEG support, followed by reductive amination with secondary amines. A strategy is also proposed for the synthesis of mixed amine/ether oligomers. The final chapter describes the experimental techniques employed

Soil moisture control of NO turnover and N₂O release in nitrogen-saturated subtropical forest soils

Acid forest soils in South China experience a chronically elevated input of atmospheric nitrogen (N), turning them into hot spots for gaseous N emissions. Soil moisture is known to be a major controller for the partitioning of gaseous N loss to nitric (NO) and nitrous oxide (N2O), which may be of particular relevance in the monsoonal climate of South China. To study this partitioning in more detail, we determined gas phase kinetics of NO and N2O release during laboratory dry-out of acidic surface soils from the headwater catchment TieShanPing (TSP), situated close to Chongqing, SW China. Soils were sampled from two hydrologically distinct environments, a well-drained hill slope (HS), and a periodically flooded groundwater discharge zone (GDZ). Production and consumption of NO were studied in an automated flow-through system purged with NO-free or NO-spiked air. Production rates peaked at 21% and 18% water filled pore space (WFPS) in HS and GDZ soils, respectively, suggesting nitrification as the dominant process of NO formation in both landscape units. In HS soils, maximum production and consumption occurred at the same WFPS, whereas GDZ soils displayed maximum NO consumption at higher WFPS than maximum production, suggesting that denitrification is an important NO sink in GDZ soils. Net N2O release was largest at 100% WFPS and declined steadily during drying. Integrated over the entire range of soil moisture, potential NO-N loss outweighed potential N2O-N loss, suggesting that N-saturated, acid forest soil is an important NO source