Effects of no-tillage and subsoil loosening on soil physical properties and crop performance : a thesis presented in partial fulfilment of the requirements for the degree of Master of Applied Science in Soil Science at Massey University

Much of New Zealand's lowland agriculture integrates animal and crop production on poorly drained, easily compacted soils. Over the years, conventional cultivation has given rise to degraded soil structure on many farms. No-tillage has been shown to avoid many of these problems but the question remains: "Where soils are compact, what combination of deep tillage and/or drainage systems and no-tillage allow for the most efficient transition from conventional cultivation to no-tillage crop establishment?" The objective of this study was to ascertain if soil properties, and crop (Brassica campestis x Brassica napus cv "Pasja" followed by wheat Triticum aestivum cv "Kohika") establishment and yield on land converted from a conventionally tilled system to a no-tillage system could be improved by various subsoiling and mole plough operations. Plots on a Milson silt loam (Argillic Perch-Gley Pallic Soil) (Typic Ochraqualf) were paraplowed (PP), straight-legged subsoiled (SL), mole ploughed (M) or were left as non-subsoiled controls (C) in the autumn of 1997. Forage brassica was then sown with a Cross-Slot™ no-tillage drill. Wheat was established on the same plots with the same no-tillage drill in the spring of 1997. Subsoiling initially reduced soil strength by a significant amount. Shortly after subsoiling cone indices showed disruption to 300 mm with PP, 350 mm with SL and 100 mm with M. At the same time, approximately 20% of profile cone indices from subsoiled treatments were greater than 2 MPa, compared to approximately 52% for C and M. At 267 days after subsoiling, PP continued to have lower cone index values than C and M. Subsoiling initially reduced bulk density. When measured in May, the bulk density of PP plots was significantly lower than SL, M and C although reconsolidation in all plots was observed in February 1998 after the wheat was harvested. Air permeability in PP, SL and M was significantly greater than in C. Despite the differences in soil strength and bulk density (but not air permeability), subsoiling and mole ploughing did not produce differences in plant populations or yield for either the winter brassica or spring-sown wheat crops. The lack of any differences for brassica crop performance criteria were in spite of the vertical rooting depth being greater in the PP treatment. The lack of differences in plant establishment and yield was thought to be due to the relatively dry autumn and winter soil conditions and the use of the Cross-Slot™ no-tillage opener which is reported to be tolerant of variable soil conditions

Symplectic fibrations and Riemann-Roch numbers of reduced spaces

In this article we give formulas for the Riemann-Roch number of a symplectic quotient arising as the reduced space corresponding to a coadjoint orbit (for an orbit close to 0) as an evaluation of cohomology classes over the reduced space at 0. This formula exhibits the dependence of the Riemann-Roch number on the Lie algebra variable which specifies the orbit. We also express the formula as a sum over the components of the fixed point set of the maximal torus. Our proof applies to Hamiltonian G-manifolds even if they do not have a compatible Kahler structure, using the definition of quantisation in terms of the Spin-C Dirac operator.Comment: 11 pages; part of the Ph.D. thesis of the first author. Section 2 revised (Section 2.1, also Theorem 2.4 and new Proposition 2.5

Inferring black-hole orbital dynamics from numerical-relativity gravitational waveforms

Binary-black-hole dynamics cannot be related to the resulting gravitational-wave signal by a constant retarded time. This is due to the non-trivial dynamical spacetime curvature between the source and the signal. In a numerical-relativity simulation there is also some ambiguity in the black-hole dynamics, which depend on the gauge (coordinate) choices used in the numerical solution of Einstein's equations. It has been shown previously that a good approximation to the direction of the binary's time-dependent orbital angular momentum $\mathbf{\hat{L}}(t)$ can be calculated from the gravitational-wave signal. This is done by calculating the direction that maximises the quadrupolar $(\ell=2,|m|=2)$ emission. The direction depends on whether we use the Weyl scalar $\psi_4$ or the gravitational-wave strain $h$, but these directions are nonetheless invariant for a given binary configuration. We treat the $\psi_4$-based direction as a proxy to $\mathbf{\hat{L}}(t)$. We investigate how well the the binary's orbital phase, $\phi_{\rm orb}(t)$, can also be estimated from the signal. For this purpose we define a quantity $\Phi(t)$ that agrees well with $\phi_{\rm orb}(t)$. One application is to studies that involve injections of numerical-relativity waveforms into gravitational-wave detector data.Comment: 12 pages with 10 figure

Should we be promoting embryo transfer at blastocyst stage?

Copyright © 2015 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.Peer reviewedPublisher PD

Open Educational Resources: A Guide for Faculty

In this session, we will discuss the following topics: What are Open Educational Resources (OER)? What can I do with OER? Where can I find OER? How can I create OER? How can I share my OER

Standardizing the Collection and Measurement of Glucose in Exhaled Breath and Its Relationship to Blood Glucose Concentrations

Blood glucose level control (glycemic control) is crucial in diabetes. Limitations in current commercially available monitoring devices include causing patient pain leading to poor blood glucose level management. The development of a non-invasive measurement system may lead to improved patient glycemic control, reducing unwanted side-effects and complications of poor blood glucose level maintenance. This work explores the use of glucose within exhaled breath in attempt to establish an indirect method of blood glucose level measurement. Specifically, exhaled breath condensate (EBC) is examined. A breath condensing unit was designed to measure the temperature of the system, flow rate, volume of expired air, ambient humidity, and remove exhaled dead volume before condensing breath. A fluorometric assay was used to analyze and measure the glucose concentrations in the EBC samples. The results directly relate to the feasibility of developing a noninvasive EBC-based glucose measuring device. A nebulizer study was performed to verify that the amount of glucose present in the condensate was predictable, given a known concentration of aerosolized glucose. The nebulizer study revealed that some glucose interferent is present in the ambient air. Further exploration allowed for a humidity based model to be developed that can accurately and consistently predict the concentration of the condensate. An IRB approved study, using a total of five human subjects, was employed to quantitatively evaluate the change in both blood and EBC glucose levels associated with the intake of either food or water. The human subject study results indicate that, with the use of the humidity based model derived from the nebulizer study, it is possible to predict blood glucose levels from EBC glucose levels. These results provide motivation for the further exploration of an EBC-based non-invasive blood monitoring device