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The report of a detection of an absorption profile centred at 78 MHz in the continuum radio background spectrum by the EDGES experiment and its interpretation as the redshifted 21 cm signal of cosmological origin has become one of the most debated results of observational cosmology in recent times. The cosmological 21 cm has long been proposed to be a powerful probe for observing the early Universe and tracing its evolution over cosmic time. Even though the science case is well established, measurement challenges posed on the technical ground are not fully understood to the level of claiming a successful detection. EDGES’s detection has naturally motivated a number of experimental attempts worldwide to corroborate the findings. In this paper, we present a precision cross-correlation spectrometer HYPEREION purpose-designed for a precision radio background measurement between 50–120 MHz to detect the absorption profile reported by the EDGES experiment. HYPEREION implements a pre-correlation signal processing technique that self-calibrates any spurious additive contamination from within the system and delivers a differential measurement of the sky spectrum and a reference thermal load internal to the system. This ensures an unambiguous “zero-point” of absolute calibration of the purported absorption profile. We present the system design, measurement equations of the ideal system, systematic effects in the real system, and finally, an assessment of the real system output for the detection of the absorption profile at 78 MHz in the continuum radio background spectrum.

Supermassive black holes and supernovae explosions at the centres of active galaxies power cycles of outflowing and inflowing gas that affect galactic evolution and the overall structure of the Universe. While simulations and observations show that this must be the case, the range of physical scales (over ten orders of magnitude) and paucity of available tracers, make both the simulation and observation of these effects difficult. By serendipity, there lies an active galaxy, Centaurus A (NGC 5128), at such a close proximity as to allow its observation over this entire range of scales and across the entire electromagnetic spectrum. In the radio band, however, details on scales of 10-100 kpc from the supermassive black hole have so far been obscured by instrumental limitations. Here we report low-frequency radio observations that overcome these limitations and show evidence for a broad, bipolar outflow with velocity 1100 km per s and mass outflow rate of 2.9 solar masses per year on these scales. We combine our data with the plethora of multi-scale, multi-wavelength historical observations of Centaurus A to probe a unified view of feeding and feedback, which we show to be consistent with the Chaotic Cold Accretion self-regulation scenario., Comment: 15 pages, 5 figures, 2 tables

The locations of Ly-$\alpha$ emitting galaxies (LAEs) at the end of the Epoch of Reionisation (EoR) are expected to correlate with regions of ionised hydrogen, traced by the redshifted 21~cm hyperfine line. Mapping the neutral hydrogen around regions with detected and localised LAEs offers an avenue to constrain the brightness temperature of the Universe within the EoR by providing an expectation for the spatial distribution of the gas, thereby providing prior information unavailable to power spectrum measurements. We use a test set of 12 hours of observations from the Murchison Widefield Array (MWA) in extended array configuration, to constrain the neutral hydrogen signature of 58 LAEs, detected with the Subaru Hypersuprime Cam in the \textit{Silverrush} survey, centred on $z$=6.58. We assume that detectable emitters reside in the centre of ionised HII bubbles during the end of reionization, and predict the redshifted neutral hydrogen signal corresponding to the remaining neutral regions using a set of different ionised bubble radii. A prewhitening matched filter detector is introduced to assess detectability. We demonstrate the ability to detect, or place limits upon, the amplitude of brightness temperature fluctuations, and the characteristic HII bubble size. With our limited data, we constrain the brightness temperature of neutral hydrogen to $\Delta{\rm T}_B, Comment: 9 pages, 6 figures, accepted for publication in MNRAS

We present an analysis of Murchison Widefield Array radio telescope data from $\omega$ Cen, possibly a stripped dwarf spheroidal galaxy core captured by our Galaxy. Recent interpretations of Fermi-LAT $\gamma$-ray data by Brown {\it et al.} (2019) and Reynoso-Cordova {\it et al.} (2019) suggest that $\omega$ Cen may contain significant Dark Matter. We utilise their best-fit Dark Matter annihilation models, and an estimate of the magnetic field strength in $\omega$ Cen, to calculate the expected radio synchrotron signal from annihilation, and show that one can usefully rule out significant parts of the magnetic field - diffusion coefficient plane using our current observational limits on the radio emission. Improvement by a factor of 10-100 on these limits could constrain the models even more tightly., Comment: Accepted in Physics of the Dark Universe, 7 pages, 4 figures, 1 table

Observations in the lowest MWA band between $75-100$ MHz have the potential to constrain the distribution of neutral hydrogen in the intergalactic medium at redshift $\sim 13-17$. Using 15 hours of MWA data, we analyse systematics in this band such as radio-frequency interference (RFI), ionospheric and wide field effects. By updating the position of point sources, we mitigate the direction independent calibration error due to ionospheric offsets. Our calibration strategy is optimized for the lowest frequency bands by reducing the number of direction dependent calibrators and taking into account radio sources within a wider field of view. We remove data polluted by systematics based on the RFI occupancy and ionospheric conditions, finally selecting 5.5 hours of the cleanest data. Using these data, we obtain two sigma upper limits on the 21 cm power spectrum in the range of $0.1\lessapprox k \lessapprox 1 ~\rm ~h~Mpc^{-1}$ and at $z$=14.2, 15.2 and 16.5, with the lowest limit being $6.3\times 10^6 ~\rm mK^2$ at $\rm k=0.14 \rm ~h~Mpc^{-1}$ and at $z=15.2$ with a possibility of a few \% of signal loss due to direction independent calibration., Comment: 17 pages, 18 figures, accepted to MNRAS

Genomic selection is expected to enhance the genetic improvement of forest tree species by providing more accurate estimates of breeding values through marker-based relationship matrices compared with pedigree-based methodologies. When adequately robust genomic prediction models are available, an additional increase in genetic gains can be made possible with the shortening of the breeding cycle through elimination of the progeny testing phase and early selection of parental candidates. The potential of genomic selection was investigated in an advanced Eucalyptus nitens breeding population focused on improvement for solid wood production. A high-density SNP chip (EUChip60K) was used to genotype 691 individuals in the breeding population, which represented two seed orchards with different selection histories. Phenotypic records for growth and form traits at age six, and for wood quality traits at age seven were available to build genomic prediction models using GBLUP, which were compared to the traditional pedigree-based alternative using BLUP. GBLUP demonstrated that breeding value accuracy would be improved and substantial increases in genetic gains towards solid wood production would be achieved. Cross-validation within and across two different seed orchards indicated that genomic predictions would likely benefit in terms of higher predictive accuracy from increasing the size of the training data sets through higher relatedness and better utilization of LD

With intensification of forest management, there has been increasing focus on the impacts of harvest residue removal on tree growth and long-term site productivity. The intensity of harvest removals, which has a direct impact on the available nutrient pools, influences tree growth and are also likely to impact the quality of wood formed. This study focused on the effects of harvesting residue removal practices (whole tree + forest floor, whole tree and stem only) at the end of the previous rotation and repeated fertiliser addition during the current rotation on selected wood quality attributes. Growth, wood density and standing tree acoustic velocity data were collected from almost 600 radiata pine (Pinus radiata D. Don) trees from long term site productivity trials across New Zealand (Woodhill, Tarawera and Berwick Forests). A sample of 116 trees were felled to obtain detailed wood quality measurements on logs and cross-sectional discs at different heights along the stem. There was little or no effect of different levels of harvesting removal on any of the measures of wood quality. However, repeated fertiliser addition throughout the course of the rotation (up to 3200 kg N ha−1 at Woodhill Forest) did result in adverse impacts on wood density, stiffness, branch size and heartwood content. The degree to which these affect returns to forest growers and end-product performance will depend on the market segment that logs are being sold into. It is recommended that nutritional strategies aimed at increasing forest productivity should incorporate studies to evaluate their potential adverse impacts on wood quality.

Modeling and simulation of vehicles in sand is critical for characterizing off-road mobility in arid and coastal regions. This paper presents improved algorithms for calculating sinkage (z) of wheeled vehicles operating on loose dry sand. The algorithms are developed based on 2737 tests conducted on sand with 23 different wheel configurations. The test results were collected from Database Records for Off-road Vehicle Environments (DROVE), a recently developed database of tests conducted with wheeled vehicles operating in loose dry sand. The study considers tire diameters from 36 to 124 cm with wheel loads of 0.19–36.12 kN. The proposed algorithms present a simple form of sinkage relationships, which only require the ratio of the wheel ground contact pressure and soil strength represented by cone index. The proposed models are compared against existing closed form solutions defined in the Vehicle Terrain Interface (VTI) model. Comparisons suggest that incorporating the proposed models into the VTI model can provide comparable predictive accuracy with simpler algorithms. In addition to simplicity, it is believed that the relationship between cone index (representing soil shear strength) and the contact pressure (representing the applied pressure to tire-soil interface) can better capture the physics of the problem being evaluated.

We explore methods for robust estimation of the 21 cm signal from the Epoch of Reionisation (EoR). A Kernel Density Estimator (KDE) is introduced for measuring the spatial temperature fluctuation power spectrum from the EoR. The KDE estimates the underlying probability distribution function of fluctuations as a function of spatial scale, and contains different systematic biases and errors to the typical approach to estimating the fluctuation power spectrum. Extraction of histograms of visibilities allows moments analysis to be used to discriminate foregrounds from 21 cm signal and thermal noise. We use the information available in the histograms, along with the statistical dis-similarity of foregrounds from two independent observing fields, to robustly separate foregrounds from cosmological signal, while making no assumptions about the Gaussianity of the signal. Using two independent observing fields to robustly discriminate signal from foregrounds is crucial for the analysis presented in this paper. We apply the techniques to 13 hours of Murchison Widefield Array (MWA) EoR data over two observing fields. We compare the output to that obtained with a comparative power spectrum estimation method, and demonstrate the reduced foreground contamination using this approach. Using the second moment obtained directly from the KDE distribution functions yields a factor of 2-3 improvement in power for k < 0.3hMpc^{-1} compared with a matched delay space power estimator, while weighting data by additional statistics does not offer significant improvement beyond that available for thermal noise-only weights., 19 pages, 18 figures, accepted for publication in MNRAS

There is an ongoing need to measure strains in reinforced concrete structures more reliably and under a range of circumstances e.g. long term durability (such as effects of cracking and reinforcement corrosion), response to normal working loads and response under abnormal load conditions. Fibre optic sensors have considerable potential for this purpose and have the additional advantages, including of immunity to electromagnetic interference and light weight (Grattan et al., 2000). This is important in railway scenarios and particularly so when the lines are electrified. Their small size allows for easy installation. However, their use as commercial ‘packaged’ devices (traditionally seen as necessary to achieve adequate robustness) is limited by their high cost relative to other sensor devices such as encapsulated electric resistance strain gauges. This paper describes preliminary work to produce a cost-effective and easy-to-use technique for encapsulating fibre optic sensors in resin using 3D printing techniques to produce a robust, inexpensive ‘packaged’ sensor system suitable for use with concrete structures. The work done to date has shown this to be a convenient and economical way of producing multiple sensors which were suitable for both surface mounting and embedment in reinforced concrete structures. The proof-of-concept testing to which the trial packages were subjected is described in the paper and the results indicate that 3D printed packages have considerable potential for further development and use in a variety of civil engineering applications, competing well with more conventional sensor systems.

We have detected 27 new supernova remnants (SNRs) using a new data release of the GLEAM survey from the Murchison Widefield Array telescope, including the lowest surface brightness SNR ever detected, G 0.1 – 9.7. Our method uses spectral fitting to the radio continuum to derive spectral indices for 26/27 candidates, and our low-frequency observations probe a steeper spectrum population than previously discovered. None of the candidates have coincidentWISEmid-IR emission, further showing that the emission is non-thermal. Using pulsar associations we derive physical properties for six candidate SNRs, finding G 0.1 – 9.7 may be younger than 10 kyr. Sixty per cent of the candidates subtend areas larger than 0.2 deg2on the sky, compared to < 25% of previously detected SNRs. We also make the first detection of two SNRs in the Galactic longitude range 220°–240°.

We examined the latest data release from the GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey covering 345°

Fiber optic sensors have considerable potential for measuring strains in the challenging environment posed by today’s civil engineering applications. Their long-term reliability and stability are particularly important attributes for assessing, with confidence, effects such as cracking and response to normal (and abnormal) loads. However, given the fragile nature of the bare fiber, the sensors must be packaged to achieve adequate robustness but the resulting increased cost of installation can frequently limit the number of sensors which can be installed or their use may have to be ruled out altogether due to these financial constraints. There is thus potential for the development of a more affordable type of packaging and this paper describes work undertaken to produce a cost-effective and easy-to-use technique for encapsulating fiber optic sensors in resin, taking advantage of 3D printing techniques which are widely available and at low cost. This approach can be used to produce a robust, inexpensive packaged sensor system which is seen as being suitable to be extended to a wider range of uses including installation in concrete structures prior to casting. To evaluate this approach, several such 3D printed package types and geometries are described and their behavior is assessed from a programme of laboratory trials, the results of which are presented in this paper. This proof-of-concept testing has demonstrated the considerable potential which 3D printed packages have and the scope for further development and consequent use in civil engineering applications. Areas showing promise and potential, which have been identified from the work undertaken, are discussed.

Soil moisture is a key terrain variable in ground vehicle off-road mobility. Historically, models of the land water balance have been used to estimate soil moisture. Recently, satellites have provided another source of soil moisture estimates that can be used to estimate soil-limited vehicle mobility. In this study, we compared the off-road vehicle mobility estimates based on three soil moisture sources: WindSat (a satellite source), LIS (a computer model source), and in situ ground sensors (to represent ground truth). Mobility of six vehicles, each with different ranges of sensitivity to soil moisture, was examined in three test sites. The results demonstrated that the effect of the soil moisture error on mobility predictions is complex and may produce very significant errors in off-road mobility analysis for certain combinations of vehicles, seasons, and climates. This is because soil moisture biases vary in both direction and magnitude with season and location. Furthermore, vehicles are sensitive to different ranges of soil moistures. Modeled vehicle speeds in the dry time periods were limited by the interaction between soil traction and the vehicles’ powertrain characteristics. In the wet season, differences in soil strength resulted in more significant differences in mobility predictions.

The compact configuration of Phase II of the Murchison Widefield Array (MWA) consists of both a redundant subarray and pseudo-random baselines, offering unique opportunities to perform sky-model and redundant interferometric calibration. The highly redundant hexagonal cores give improved power spectrum sensitivity. In this paper, we present the analysis of nearly 40 hours of data targeting one of the MWA's EoR fields observed in 2016. We use both improved analysis techniques presented in Barry et al. (2019) as well as several additional techniques developed for this work, including data quality control methods and interferometric calibration approaches. We show the EoR power spectrum limits at redshift 6.5, 6.8 and 7.1 based on our deep analysis on this 40-hour data set. These limits span a range in $k$ space of $0.18$ $h$ $\mathrm{Mpc^{-1}}$ $

We describe the motivation and design details of the "Phase II" upgrade of the Murchison Widefield Array (MWA) radio telescope. The expansion doubles to 256 the number of antenna tiles deployed in the array. The new antenna tiles enhance the capabilities of the MWA in several key science areas. Seventy-two of the new tiles are deployed in a regular configuration near the existing MWA core. These new tiles enhance the surface brightness sensitivity of the MWA and will improve the ability of the MWA to estimate the slope of the Epoch of Reionisation power spectrum by a factor of ~3.5. The remaining 56 tiles are deployed on long baselines, doubling the maximum baseline of the array and improving the array u,v coverage. The improved imaging capabilities will provide an order of magnitude improvement in the noise floor of MWA continuum images. The upgrade retains all of the features that have underpinned the MWA's success (large field-of-view, snapshot image quality, pointing agility) and boosts the scientific potential with enhanced imaging capabilities and by enabling new calibration strategies., Comment: 11 pages, 8 figs. Accepted for publication in PASA

Stem guying to prevent wind-induced swaying of radiata pine trees resulted in significant changes in radial growth, but did not affect the frequency of compression wood or resin features. Mechanical stress resulting from wind forces acting on trees can cause a number of direct and indirect effects ranging from microscopic changes in cambial activity through to stem breakage and uprooting. To better understand these effects on radial stem growth and wood properties, an experiment was established in a 13-year-old radiata pine (Pinus radiata D Don) stand in which 20 trees were guyed to prevent them from swaying. Radial growth was monitored in these trees and 20 matched controls at monthly intervals for 5 years. The trees were then felled and radial growth, resin features and compression wood were assessed on cross-sectional discs taken at fixed locations up the stem. There was a significant reduction in radial growth at breast height (1.4 m above the ground) in the guyed trees, but an increase in growth immediately above the guying point. A total of 277 resin features were observed in the growth rings formed following guying. The overall frequency of such features was related to height within the stem and annual ring number. No effect of stem guying was found on the incidence of compression wood. Interestingly, the distribution of resin features also did not differ between guyed and un-guyed trees. There was no evidence of a link between stem restraint as a result of guying and the incidence of resin features, suggesting that other factors, such as soil moisture may be more influential.

Wood density is considered a primary property because of its strong correlation with stem stiffness, and also because it is central to the accounting of carbon sequestration in plantations. Using an extensive dataset (n = 1214) of Pinus radiata outerwood density, the objectives of this research were to (i) develop a model of outerwood density, (ii) characterise the functional form of the relationships found between independent variables and outerwood density, (iii) from the final model develop a P. radiata outerwood density map for New Zealand, and (iv) investigate the influence of spatial scale on the accuracy of model predictions. Validation data (n = 200) found the final model accounted for 70% of the variance in outerwood density. The model included three significant (P

Genomic selection is expected to enhance the genetic improvement of forest tree species by providing more accurate estimates of breeding values through marker-based relationship matrices compared with pedigree-based methodologies. When adequately robust genomic prediction models are available, an additional increase in genetic gains can be made possible with the shortening of the breeding cycle through elimination of the progeny testing phase and early selection of parental candidates. The potential of genomic selection was investigated in an advanced Eucalyptus nitens breeding population focused on improvement for solid wood production. A high-density SNP chip (EUChip60K) was used to genotype 691 individuals in the breeding population, which represented two seed orchards with different selection histories. Phenotypic records for growth and form traits at age six, and for wood quality traits at age seven were available to build genomic prediction models using GBLUP, which were compared to the traditional pedigree-based alternative using BLUP. GBLUP demonstrated that breeding value accuracy would be improved and substantial increases in genetic gains towards solid wood production would be achieved. Cross-validation within and across two different seed orchards indicated that genomic predictions would likely benefit in terms of higher predictive accuracy from increasing the size of the training data sets through higher relatedness and better utilization of LD.

Women appear in different lights in the Essays; Montaigne can alternately praise and disparage them. He often presents them in binary opposition to men, but at times he subtly aligns himself with them, thereby troubling that binary divide that had characterized men’s writings about women since antiquity. The Essays record his ongoing questioning about the nature of women and their relationship to men. Montaigne recognized the political influence of certain noble women. Although he rarely mentions the women in his family, they were a prominent presence in his home life, and his essays obliquely reflect his experiences with them. Finally, the dedication of a woman guaranteed the posterity of his Essays through a series of editions into the seventeenth century, and in the twentieth century a woman became the first scholar and editor of Montaigne in North America.

The Detection of redshifted 21 cm emission from the epoch of reionization (EoR) is a challenging task owing to strong foregrounds that dominate the signal. In this paper, we propose a general method, based on the delay spectrum approach, to extract HI power spectra that is applicable to tracking observations using an imaging radio interferometer (Delay Spectrum with Imaging Arrays (DSIA)). Our method is based on modelling the HI signal taking into account the impact of wide field effects such as the $w$-term which are then used as appropriate weights in cross-correlating the measured visibilities. Our method is applicable to any radio interferometer that tracks a phase center and could be utilized for arrays such as MWA, LOFAR, GMRT, PAPER and HERA. In the literature the delay spectrum approach has been implemented for near-redundant baselines using drift scan observations. In this paper we explore the scheme for non-redundant tracking arrays, and this is the first application of delay spectrum methodology to such data to extract the HI signal. We analyze 3 hours of MWA tracking data on the EoR1 field. We present both 2-dimensional ($k_\parallel,k_\perp$) and 1-dimensional (k) power spectra from the analysis. Our results are in agreement with the findings of other pipelines developed to analyse the MWA EoR data., Comment: 17 pages, 10 figures, accepted for publication in The Astrophysical Journal

Infrared-faint radio sources (IFRS) are a class of radio-loud (RL) active galactic nuclei (AGN) at high redshifts (z > 1.7) that are characterised by their relative infrared faintness, resulting in enormous radio-to-infrared flux density ratios of up to several thousand. We aim to test the hypothesis that IFRS are young AGN, particularly GHz peaked-spectrum (GPS) and compact steep-spectrum (CSS) sources that have a low frequency turnover. We use the rich radio data set available for the Australia Telescope Large Area Survey fields, covering the frequency range between 150 MHz and 34 GHz with up to 19 wavebands from different telescopes, and build radio spectral energy distributions (SEDs) for 34 IFRS. We then study the radio properties of this class of object with respect to turnover, spectral index, and behaviour towards higher frequencies. We also present the highest-frequency radio observations of an IFRS, observed with the Plateau de Bure Interferometer at 105 GHz, and model the multi-wavelength and radio-far-infrared SED of this source. We find IFRS usually follow single power laws down to observed frequencies of around 150 MHz. Mostly, the radio SEDs are steep, but we also find ultra-steep SEDs. In particular, IFRS show statistically significantly steeper radio SEDs than the broader RL AGN population. Our analysis reveals that the fractions of GPS and CSS sources in the population of IFRS are consistent with the fractions in the broader RL AGN population. We find that at least 18% of IFRS contain young AGN, although the fraction might be significantly higher as suggested by the steep SEDs and the compact morphology of IFRS. The detailed multi-wavelength SED modelling of one IFRS shows that it is different from ordinary AGN, although it is consistent with a composite starburst-AGN model with a star formation rate of 170 solar masses per year., 25 pages, 7 figures, 5 tables, accepted for publication in A&A

Using a sample of 364 female nurses, we examined relationships among emotional organizational family support, instrumental organizational family support, core self-evaluations (CSE), and burnout. Hierarchical regression analyses revealed that organizational family support (both emotional and instrumental support) and CSE were each negatively associated with nurses’ burnout. We also found that CSE moderated both emotional organizational family support – burnout relationship and instrumental organizational family support – burnout relationship, but with different patterns. Specifically, nurses with higher CSE experienced less burnout than those with lower CSE when organization provided more instrumental family support. On the other hand, nurses with lower CSE experienced less burnout than those with higher CSE when more emotional organizational family support was provided. Implications for practice and theory are discussed.

Spiral grain angle (SGA) is a wood property that has a strong influence on end-product quality, particularly for solid timber, and most commercial log and timber grading rules restrict the amount of visible surface sloping grain. The aim of this study was to develop parametric models that can be used to predict the intra- and inter-stem variation in SGA in radiata pine (Pinus radiata D.Don) trees growing in New Zealand. Empirical models were developed using a dataset that contained records from over 1,100 trees that had SGA measured in both the radial direction and at different heights up the stem. Linear and nonlinear model forms were evaluated for their ability to predict the radial variation in SGA. Most values of spiral grain angle were between −5° and +10°, with a few extreme values (up to 20°) observed. A simple linear model based on cambial age was able to account for the radial variation in SGA outside of the innermost growth rings, but only explained 26 % of the overall variation in SGA. Including a relative height term in this linear model increased the proportion of variation in SGA explained to 30 %. A variance components analysis showed that 78 % of the variation in SGA occurred within individual stems, with only 7 % of the variation due to differences between sites. Our results confirmed that SGA decreased from the inner growth rings to the bark and increased with height up the stem, with low values of SGA only found in the lower peripheral part of the stem. Given that the data came from a wide range of sites, the relatively small amount of inter-site variation was unexpected. The models developed here can be incorporated into a growth and yield simulation system to enable forest managers to compare the potential impacts of different factors on the size of the corewood zone in a tree containing wood with high SGA.

We compare first order (refractive) ionospheric effects seen by the Murchison Widefield Array (MWA) with the ionosphere as inferred from Global Positioning System (GPS) data. The first order ionosphere manifests itself as a bulk position shift of the observed sources across an MWA field of view. These effects can be computed from global ionosphere maps provided by GPS analysis centres, namely the Center for Orbit Determination in Europe (CODE), using data from globally distributed GPS receivers. However, for the more accurate local ionosphere estimates required for precision radio astronomy applications, data from local GPS networks needs to be incorporated into ionospheric modelling. For GPS observations, the ionospheric parameters are biased by GPS receiver instrument delays, among other effects, also known as receiver Differential Code Biases (DCBs). The receiver DCBs need to be estimated for any non-CODE GPS station used for ionosphere modelling, a requirement for establishing dense GPS networks in arbitrary locations in the vicinity of the MWA. In this work, single GPS station-based ionospheric modelling is performed at a time resolution of 10 minutes. Also the receiver DCBs are estimated for selected Geoscience Australia (GA) GPS receivers, located at Murchison Radio Observatory (MRO1), Yarragadee (YAR3), Mount Magnet (MTMA) and Wiluna (WILU). The ionospheric gradients estimated from GPS are compared with the ionospheric gradients inferred from radio source position shifts observed with the MWA. The ionospheric gradients at all the GPS stations show a correlation with the gradients observed with the MWA. The ionosphere estimates obtained using GPS measurements show promise in terms of providing calibration information for the MWA.

Structural monitoring using optical fibre technology may be undertaken to establish the long-term behaviour of structures, components and materials of construction. Condition monitoring may be used as an aid to repair and strengthening schedules. The establishment of material durability is also part of the monitoring process. The paper describes and discusses the application and development of the use of optical fibres to monitor structures. Examples have been given in which strain, temperature and moisture content have been determined for structural elements and materials of construction. Of particular interest is the use of an optical fibre monitoring system to determine the performance of an actual bridge, which has been subjected to controlled loading conditions. The results, which have been described, demonstrate the enormous potential to monitor structures using optical fibres.

Biosolids have been applied to a 1000 ha Pinus radiata D. Don plantation in Nelson, New Zealand, since 1996. A research trial was established in a 6-year-old stand in 1997 with three stocking rates (300, 450, and 600 stems·ha–1), and biosolids were applied at ages 6, 9, and 12 years at three application rates based on total nitrogen loading at each application of 0 (control), 300 (standard), and 600 kg N·ha–1 (high). The aim of this study was to evaluate the responses of tree growth rate and wood properties to biosolids application at midrotation. Since the trial was established, tree diameter and volume increment in the biosolids-treated plots have increased markedly. This increase in growth is being maintained at midrotation, with the year 13–14 volume increment being 40% greater in the standard treatment than the control, and 46% greater in the high treatment than the control. The response in growth has occurred across all stockings in the trial, although there has been a tendency for the difference in growth between the standard and high rates to be greater at higher stockings. A small but significant reduction of basic wood density and standing-tree sonic velocity in P. radiata was found in the biosolids treatments. Although the reductions in wood density and stiffness may slightly decrease the average log value in biosolids treated trees, this will be greatly outweighed by the large increase in wood volume.

A fibre-optic-based humidity sensor has been developed and used for the measurement of moisture absorption in concrete. The sensor was fabricated using a fibre Bragg grating (FBG) coated with a moisture sensitive polymer. To investigate the use of this sensing technique for the detection of moisture ingress in concrete, the sensor was embedded in various concrete samples of different water to cement ratios which were then immersed in a water bath. A direct indication of the humidity level within a sample is given by the shift of the Bragg wavelength caused by the expansion of the humidity-sensitive material coated on the fibre. The sensor itself exploits the inherent characteristics of the FBG, with its operation being based on the strain effect induced in the Bragg grating, through the swelling of the polymer coating. It was found that optical-fibre-based humidity sensors of this type form a basis for determining the changes in the moisture content in different concrete samples, indicating potential new applications of the sensor system to ensure the integrity of civil engineering structures in which they are used.

A multiplexed optical fiber Bragg grating sensor system with a measurement bandwidth of up to 200 Hz enabling dynamic loading events, e.g., road traffic, to be observed has been designed, installed, and tested over an 18-month period on a 346-m road bridge in Norway, for design verification and structural integrity monitoring purposes. A network of 32 fiber Bragg sensors was surface bonded along with a corresponding set of resistive strain gauges for comparative tests to be made. The wavelength data were calibrated against two thermally stabilized (/spl sim/0.15 pm) reference gratings, which rejected common mode noise and provided absolute wavelength scaling. These data provides independent strain and temperature information. Long-term test results showed good linearity and repeatability of

Esprit abstraict, ravy, et ecstatic, Qui frequentant les cieulx, ton origine, As delaisse ton hoste et domestic, Ton corps concords, qui tant se morigine A tes edictz, en vie peregrine Sans sentement, et comme en Apathie: Vouldrois tu poinct faire quelque sortie De ton manoir divin, perpetuel? Et ca bas veoir une tierce partie Des faictz joyeux du bon Pantagruel Francois Rabelais a l'esprit de la royne de Navarre, Tiers Livre. 1546 (1) En 1545, quatre ans avant la mort de Marguerite de Navarre, Francois Rabelais lui dedie son Tiers Livre. Rabelais s'adresse a Marguerite comme a une mystique. Le dizain de dedicace evoque le voyage de l'esprit qui, ayant abandonne le corps ca bas sur terre, est retourne aux cieux, lieu divin de son origine. Le dizain nous permet d'apprecier toute une gamme de voyages dans la vie et dans les oeuvres de ces deux auteurs : voyages vecus, voyages thematiques et metaphoriques, voyages associes par convention a differents genres litteraires, voyages intertextuels, voyages d'ouverture vers le monde et voyages de retraite, voyages vers Dieu par divers chemins. Rabelais se plait ici a jouer sur les conventions du discours mystique qui remontent a l'Antiquite grecque et chretienne, conventions cheres aux auteurs du seizieme siecle. Erasme, dont la presence est manifeste dans le Tiers Livre, avait evoque l'experience mystique a la fin de l'Eloge de la Folie (2). La Folie en parle comme d'un voyage et d'une alienation: "Et quand l'ame s'entraine a voyager loin du corps et n'utilise plus normalement ses organes, on a raison sans aucun doute d'appeler cela de l'alienation". Elle appelle cette alienation "une sorte de delire" et elle l'explique ainsi: "ceux a qui il a ete permis de ressentir cela eprouvent quelque chose de tres semblable a la demence: ... ils sont en somme vraiment tout entiers hors d'eux-memes" (3). Mais le mystique en extase trouble souvent ses compagnons, qui veulent le faire "revenir" dans son corps. Erasme et ses lecteurs connaissaient bien cette voix terrestre qui vient interrompre l'extase. C'est celle d'Alcibiade ivre, qui fait irruption a la fin du Banquet de Platon, au moment ou Socrate termine le recit du discours de Diotime. Erasme avait exploite le discours d'Alcibiade dans son adage, Sileni Alcibiadis, et Rabelais, a son tour, avait imite cet adage dans le prologue de Gargantua. Dans Le Livre du Courtisan (1528), Castiglione avait represente la tension entre l'extase et les forces terrestres dans la conclusion du discours sur l'Amour (imite de celui de Diotime), prononcee par Bembo: Bembo, qui avait parle jusqu'ici avec tant de vehemence qu'il semblait etre dans un etat de ravissement et presque hors de lui, restait silencieux et immobile, les yeux tournes vers le ciel, comme frappe de stupeur, quand madame Emilia, qui, avec les autres, avait ecoute avec beaucoup d'attention son propos, le prit par le pan de son vetement, et, le secouant un peu, dit: "Prenez garde, messire Pietro, qu'avec ces pensees, votre ame a vous aussi ne se separe pas de votre corps" (4). Dans son dizain de dedicace du Tiers Livre a l'esprit de la reine de Navarre, Rabelais joue le role d'Emilia et d'Alcibiade vis-a-vis de Marguerite. Le dizain met en scene une rencontre textuelle entre deux auteurs des plus eminents des annees 1540--et a bien des egards des plus disparates. Nous ne savons pas si Rabelais et Marguerite se sont rencontres dans la vie. Pierre Jourda se pose la question: "Connaissait-elle Rabelais?" et repond que, "La chose est probable". Le dizain permet-il des conjectures a ce sujet? Dans son edition du Tiers Livre (1995), Jean Ceard avance que: "Cette dedicace, qui n'a pas pu etre ecrite et publiee sans son consentement, prouve que la reine soutient ouvertement Rabelais". Edwin Duval voit pourtant un ton critique, meme moqueur, dans le dizain, qu'il qualifie d'"etonnant dans son portrait peu flatteur" de la reine (5). …

Double Skin Composite (DSC) or Steel–Concrete–Steel sandwich construction was first conceived over 14 years ago for use in submerged tube-tunnel construction in the UK [1] . More recently, British Steel plc (now Corus UK) have developed the original shear-stud concept to currently friction-weld round steel bars to both plates in a simultaneous operation. This process not only makes the units easy to handle, but also provides sufficient strength to resist the internal hydrostatic pressures due to fresh concrete. This product is called Bi-Steel. This paper outlines a programme of research conducted at City University, in which the elastic and plastic behaviour of a series of 16 large-scale, simply supported, three-point bending tests were investigated [2] . These tests compare existing and new construction methods, and were conducted until collapse due to local buckling of the compression plate. The test programme is supported by a series of analytical solutions covering the elastic and plastic performance of the specimens.

We investigated the influence of using three different soil moisture sources WindSat (a satellite), land information system (LIS) (a computer model), and in situ ground sensors in a full-featured ground vehicle mobility analysis model. Soil moisture, soil type, land use, and slope were used to estimate the mobility in dry and wet scenarios for six vehicles using the NATO Reference Mobility Model (NRMM). The dry scenario showed nearly the same results for all three soil moisture sources. In the wet scenario, modelled travel times based on LIS were about 26% faster compared to those from the in situ moisture. Modelled times based on WindSat averaged 11% slower than those from the in situ moisture. For the test case we found agreement between the results of the current full-feature model against a previously-developed model using only soil moisture time series. This demonstrates that soil moisture can be important even as one terrain factor among many.

This paper describes the concept and field testing of a hollow, cast-in-situ, rotary bored pile foundation 1200 mm diameter and 30 m deep. The aim of the foundation is to allow large-diameter piles to be constructed using less concrete than in an equivalent conventional solid pile, and with a view to allowing reuse at a later date. Reuse is made possible because the hollow core of the pile allows access for inspection after demolition of an existing structure. The new piles may also allow modification to enhance load capacity by augering through the base and extending their length. In addition, the piles are better suited than conventional piles for use as ‘energy piles' to allow environmentally friendly heating and cooling. The geotechnical performance of the hollow test pile was comparable with that of a conventional solid pile constructed during the same trial. Details of construction are given, including lessons learned.

A qualitative study was conducted using focus group methodology to obtain the knowledge, attitudes, beliefs, programmatic suggestions as well as communication strategies for HIV prevention from four specific types of high-risk youth: incarcerated/detained youth, homeless/runaway youth, school aged youth, and alcohol and other drug using youth (in school). Eleven focus groups were conducted. No meaningful differences were found in issues across the four groups; however, there were differences with regard to gender. Youth provided specific suggestions for providing HIV prevention programs which include communication strategies. The results will be used to facilitate in the development and implementation of appropriate HIV prevention measures in eight counties of a predominantly rural south-eastern State.