Are We Ignoring Science in our Quest for Simplicity in Range Management?

Accurate determination of range condition and trend is essential for proper range management. In the United States, the range condition model currently used is not based on up-to-date ecological knowledge. It assumes a single stable state (climax) and linear pathways. Multiple stable state models more accurately depict community dynamics but have not been widely accepted. U.S. Federal land management agencies are using surrogates, such as qualitative “instant trend” measures and substitution of utilization for measured condition and trend to guide management. Most of these short cuts are not based on science. Attacks on livestock grazing by environmentalists are based on inaccurate assumptions about the effect of grazing on biodiversity

Long-term Properties of Accretion Disks in X-ray Binaries: II. Stability of Radiation-Driven Warping

A significant number of X-ray binaries are now known to exhibit long-term ``superorbital'' periodicities on timescales of $\sim$ 10 - 100 days. Several physical mechanisms have been proposed that give rise to such periodicities, in particular warping and/or precession of the accretion disk. Recent theoretical work predicts the stability to disk warping of X-ray binaries as a function of the mass ratio, binary radius, viscosity and accretion efficiency, and here we examine the constraints that can be placed on such models by current observations. In paper I we used a dynamic power spectrum (DPS) analysis of long-term X-ray datasets (CGRO, RXTE), focusing on the remarkable, smooth variations in the superorbital period exhibited by SMC X-1. Here we use a similar DPS analysis to investigate the stability of the superorbital periodicities in the neutron star X-ray binaries Cyg X-2, LMC X-4 and Her X-1, and thereby confront stability predictions with observation. We find that the period and nature of superorbital variations in these sources is consistent with the predictions of warping theory. We also use a dynamic lightcurve analysis to examine the behaviour of Her X-1 as it enters and leaves the 1999 Anomalous Low State (ALS). This reveals a significant phase shift some 15 cycles before the ALS, which indicates a change in the disk structure or profile leading into the ALS.Comment: 12 pages, 14 figures, Re-submitted to MNRAS after referee's comment

A socio-economic investigation of pre-harvest and post-harvest crop loss between producers and retailers in Fenland

This paper presents the results of an investigation which identified causes of both pre- and post-harvest crop losses and retail-induced crop losses within Fenland, Cambridgeshire. This study used semi-structured face-to-face interviews with local fruit and vegetable producers. Constructivist grounded theory was utilised for data analysis which revealed aspects not previously identified within academic literature. The causes of crop loss are heavily influenced by external forces situated near the consumer-end of the food supply chain in addition to natural factors, such as weather events, were identified to form a small percentage of loss. While crop loss cannot be totally mitigated; producers appear to use a plethora of strategies including the use of technology to minimise these losses. Producers were found to be directly affected by the high demands of retailers and consumers, however, the significance was found to be dependent on the scale of production and the crop grown. This study establishes the need for new future policies to ensure equality for producers in the UK fresh food supply chain, in addition to the promotion of sustainable food production

The H1 Forward Track Detector at HERA II

In order to maintain efficient tracking in the forward region of H1 after the luminosity upgrade of the HERA machine, the H1 Forward Track Detector was also upgraded. While much of the original software and techniques used for the HERA I phase could be reused, the software for pattern recognition was completely rewritten. This, along with several other improvements in hit finding and high-level track reconstruction, are described in detail together with a summary of the performance of the detector.Comment: Minor revision requested by journal (JINST) edito

North Stradbroke Island

The islands bordering Moreton Bay to its east are vegetated dunes formed during a past period of intense wind activity. Aeolian sand, as indicated by drilling, occurs to considerable depth below sea level. There is also evidence of sub-aerial weathering in bedrock samples and this implies subsequent drowning of the land surface. The occurrence of colouration (red, brown, grey) in much of the dune mass is thought to be due to decomposition of some of the disseminated heavy minerals - the older more leached dune sand being quite white in appearance. Of particular interest is the occurrence within the dunes of white argillaceous and black humate cemented sands, which have formed at the groundwater surface on interception of downward percolating products of leaching

AX J0049.4-7323 - a close look at a neutron star interacting with a circumstellar disk

Detailed evidence on the system AX J0049.4-7323 is presented here to show how the passage of the neutron star in the binary system disrupts the circumstellar disk of the mass donor Be star. A similar effect is noted in three other Be/X-ray binary systems. Together the observational data should provide valuable tools for modelling these complex interactions.Comment: 4 pages, accepted for publication in MNRA

Effects of Tape Recorded Textbook Passages upon Social Studies Achievement of Selected Elementary School Intermediate Pupils

Elementary Educatio

The binary period and outburst behaviour of the SMC X-ray binary pulsar system SXP504

A probable binary period has been detected in the optical counterpart to the X-ray source CXOU J005455.6-724510 = RX J0054.9-7245 = AXJ0054.8-7244 = SXP504 in the Small Magellanic Cloud. This source was detected by Chandra on 04 Jul 2002 and subsequently observed by XMM-Newton on 18 Dec 2003. The source is coincident with an Optical Gravitational Lensing (OGLE) object in the lightcurves of which several optical outburst peaks are visible at ~ 268 day intervals. Timing analysis shows a period of 268.6 +/- 0.1 days at > 99% significance. Archival Rossi X-ray Timing Explorer (RXTE) data for the 504s pulse-period has revealed detections which correspond closely with predicted or actual peaks in the optical data. The relationship between this orbital period and the pulse period of 504s is within the normal variance found in the Corbet diagram.Comment: Accepted by MNRAS. 1 LATEX page. 4 figure