Technical note Cost-estimating procedures for drip-, micro- and furrow-irrigation systems

The total annual fixed and operating costs of a drip-, micro- and furrow-irrigation system were estimated, as well as the marginal factor cost of water applied. An existing centre-pivot irrigation cost-estimating procedure was used. The type of irrigation system data needed are specified. The assumptions about the salvage value and expected lifespan of the system components are given. The total investment cost of the drip-, micro- and furrow-irrigation system is R200 000, R277 586 and R132 012 respectively. The total annual fixed and operating costs of the drip-, micro- and furrow-irrigation system are R28 509, R39 817 and R17 763 (fixed) and R36 957, R38 980 and R106 375 (operating) respectively. The marginal factor cost of water applied for the drip-, micro- and furrow-irrigation systems is R2.00/mm·ha, R1.90/mm·ha and R2.20/mm·ha. The proper estimation of irrigation costs is critical for irrigators to be able to evaluate efficient water use techniques. Water SA Vol.31 (3) 2005: pp.403-40

The radiation of cynodonts and the ground plan of mammalian morphological diversity

Cynodont therapsids diversified extensively after the Permo-Triassic mass extinction event, and gave rise to mammals in the Jurassic. We use an enlarged and revised dataset of discrete skeletal characters to build a new phylogeny for all main cynodont clades from the Late Permian to the Early Jurassic, and we analyse models of morphological diversification in the group. Basal taxa and epicynodonts are paraphyletic relative to eucynodonts, and the latter are divided into cynognathians and probainognathians, with tritylodonts and mammals forming sister groups. Disparity analyses reveal a heterogeneous distribution of cynodonts in a morphospace derived from cladistic characters. Pairwise morphological distances are weakly correlated with phylogenetic distances. Comparisons of disparity by groups and through time are non-significant, especially after the data are rarefied. A disparity peak occurs in the Early/Middle Triassic, after which period the mean disparity fluctuates little. Cynognathians were characterized by high evolutionary rates and high diversity early in their history, whereas probainognathian rates were low. Community structure may have been instrumental in imposing different rates on the two clades

Heritability of live weight and condition score in a Holstein herd and correlations with milk traits – preliminary estimat

Genetic and environmental parameters for live weight and condition score have been determined for Holstein cows. Genetic correlations with milk traits were also derived. Monthly records were modelled by cubic splines, while the direct, additive effects of animal and the temporary environment (defined as cow environmental effects within lactations) were fitted as random. Lactation number interacted with monthly trends in cow live weight. Cows lost weight in the early part of the lactation. This reduction in live weight was probably because of a loss in body reserves, as suggested by a lower condition score. Cows gained live weight towards the end of lactation. The ultimate live weight of cows increased with parity because of ongoing growth. The heritability (h²) estimate for live weight was high at 0.65 ± 0.04, albeit still within the expected range. Condition score had a medium h² of 0.24 ± 0.05. Genetic and phenotypic correlations of live weight with milk yield were positive, i.e. 0.19 ± 0.14 and 0.12 ± 0.05, respectively, while correlations of condition score with milk yield were negative, i.e. 0.42 ± 0.15 and -0.17 ± 0.04, respectively. Although live weight could be used as an indirect indicator of feed intake and efficiency of milk production, other body conformation traits could also be used. There is a need in the South African dairy industry for a selection index based on production parameters and some traits such as live weight, condition score or specific conformation traits. However, a large participation of animals in milk recording and measurement of such traits is a prerequisite for such developments. South African Journal of Animal Science Vol. 36(2) 2006: 79-8

Predictions of DKIST/DL-NIRSP observations for an off-limb kink-unstable coronal loop

This is the author accepted manuscript. The final version is available from the American Astronomical Society via the DOI in this record.Synthetic intensity maps are generated from a 3D kink-unstable ux rope simulation using several DKIST/DL-NIRSP spectral lines to make a prediction of the observational signatures of energy transport and release. The reconstructed large eld-of-view intensity mosaics and single tile sit-and-stare high-cadence image sequences show detailed, ne-scale structure and exhibit signatures of wave propagation, redistribution of heat, ows and ne-scale bursts. These ne-scale bursts are present in the synthetic Doppler velocity maps and can be interpreted as evidence for small-scale magnetic reconnection at the loop boundary. The spectral lines reveal the di erent thermodynamic structures of the loop, with the hotter lines showing the loop interior and braiding, and the cooler lines showing the radial edges of the loop. The synthetic observations of DL-NIRSP are found to preserve the radial expansion and hence the loop radius can be measured accurately. The electron number density can be estimated using the intensity ratio of the Fe xiii lines at 10747 and 10798 A. The estimated density from this ratio is correct to within 10% during the later phases of the evolution, however it is less accurate initially when line-of-sight density inhomogeneities contribute to the Fe xiii intensity, resulting in an overprediction of the density by 30%. The identi ed signatures are all above a conservative estimate for instrument noise and therefore will be detectable. In summary, we have used forward modelling to demonstrate that the coronal o -limb mode of DKIST/DL-NIRSP will be able to detect multiple independent signatures of a kink-unstable loop and observe small-scale transient features including loop braiding/twisting and small-scale reconnection events occurring at the radial edge of the loop.BS was supported by the STFC grant ST/M000826/1. PRY acknowledges funding from NASA grant NNX15AF25G. GJJB, ES and JAM acknowledge STFC for IDL support as well as support via ST/L006243/1

Phase Mixing of Alfvén Waves Near a 2D Magnetic Null Point

The propagation of linear Alfvén wave pulses in an inhomogeneous plasma near a 2D coronal null point is investigated. When a uniform plasma density is considered, it is seen that an initially planar Alfvén wavefront remains planar, despite the varying equilibrium Alfvén speed, and that all the wave collects at the separatrices. Thus, in the non-ideal case, these Alfvénic disturbances preferentially dissipate their energy at these locations. For a non-uniform equilibrium density, it is found that the Alfvén wavefront is significantly distorted away from the initially planar geometry, inviting the possibility of dissipation due to phase mixing. Despite this however, we conclude that for the Alfvén wave, current density accumulation and preferential heating still primarily occur at the separatrices, even when an extremely non-uniform density profile is considered

Effects of Chitin and Contact Insecticide Complexes on Rove Beetles in Commercial Orchards

A five-year research project was performed to explore the potential effects of contact insecticide applications on the change of abundance and species richness of predatory rove beetles (Coleoptera: Staphylinidae) in conventionally managed orchards. Twelve blocks of nine orchards were used for this study in Central Europe. High sensitivity atomic force microscopic examination was carried out for chitin structure analyses as well as computer simulation for steric energy calculation between insecticides and chitin. The species richness of rove beetles in orchards was relatively high after insecticide application. Comparing the mean abundance before and after insecticide application, a higher value was observed before spraying with alphacypermethrin and lambda-cyhalothrin, and a lower value was observed in the cases of diflubenzuron, malathion, lufenuron, and phosalone. The species richness was higher only before chlorpyrifos-methyl application. There was a negative correlation between abundance and stability value of chitin-insecticides, persistence time, and soil absorption coefficients. Positive correlation was observed with lipo- and water solubility

A Novel Technology for Complex Rheological Measurements

As the UK nuclear industry embarks on a second phase of nuclear power generation, the industry is faced with numerous sludge and slurry challenges associated with the decommissioning and clean-up of historical nuclear sites. The remediation of Sellafield, the largest nuclear site in the UK, is anticipated to cost GBP 53bn over the next 100 years. Substantial cost is associated with the clean-up, transfer and safe storage of legacy particulate wastes encountered in ponds, silos, highly active storage tanks and many more large tanks on site. To develop suitable design strategies for the mobilization and transfer of sludge, the rheology of the sludge should be accurately determined. The current work demonstrates the use of a Quartz Crystal Microbalance to measure sludge rheology, specifically the shear yield stress. The device is simple to operate with no mechanical parts, small and portable enabling deployment into limited access areas, and eliminates the need for operator sampling and laboratory measurement. The measurement principle relates to the resonance frequency and motional resistance of a piezo-electric sensor as the sensor is submerged in the desired test material. The air-to-sample frequency and resistance shifts are shown to correlate with the shear yield stress of the suspension as measured by conventional vane viscometry. As the particle network stiffens (increased yield stress), the sensor motional resistance and its resonant frequency become more positive These characteristic responses and their correlation to the shear yield stress have been confirmed for a range of particle suspensions

Quartz crystal microbalance as a device to measure the yield stress of colloidal suspensions

The application of quartz crystal microbalance (QCM) as a device to measure the rheology of colloidal suspensions has been studied. Using a commercial dip-probe QCM, the yield stress of magnesium hydroxide suspensions has been correlated to the resonance properties of a 5 MHz AT-cut quartz sensor. A stable resonance baseline was first established in air before submerging the sensor into the colloidal suspension. The response of the sensor resistance was shown to correlate to changes in the suspension yield stress, while the frequency response was found to result from more complex contact mechanics and suspension viscoelasticity contributions. Since the QCM is a relatively simple technique with no mechanically moving parts, this approach offers the potential for rapid in situ rheology assessment

Liver Transplantation for Hepatocellular Carcinoma

Background: Orthotopic liver transplantation (OLT) is the best available option for early hepatocellular carcinoma (HCC), although its application is limited by stringent selection criteria, costs, and deceased donor graft shortage, particularly in Asia, where living donor liver transplant (LDLT) has been developed. Methods: This article reviews the present standards for patient selection represented by size-and-number criteria with particular references to Milan Criteria and novel prediction models based on results achieved in patients exceeding those limits, with consideration of the expanded indication represented by the UCSF Criteria. Results: The expected outcomes after deceased donor liver transplant (DDLT) or LDLT are favorable if predetermined selection criteria are applied. However, selection bias, difference in waiting time, and ischemia-regeneration injuries of the graft among DDLT vs LDLT may influence long-term results. In the article, the differences between East and West in first-line treatments for HCC (resection vs transplantation), indications, and ethics for the donor, are summarized as well as possible novel predictors of tumor biology (especially DNA mutation and fractional allelic loss, FAI) to be considered for better outcome prediction. Conclusions: Liver transplantation remains the most promising product of modern surgery and represents a cornerstone in the management of patients with HCC. © 2007 The Author(s)