X-Ray Absorption from the Milky Way Halo and the Local Group

Million degree gas is present at near-zero redshift and is due either to a gaseous Galactic Halo or a more diffuse but very massive Local Group medium. We can discriminate between these models because the column densities should depend on location in the sky, either relative to the Galaxy bulge or to the M31-Milky Way axis. To search for these signatures, we measured the OVII Kalpha absorption line strength toward 25 bright AGNs, plus LMC X-3, using XMM-Newton RGS archival data. The data are in conflict with a purely Local Group model, but support the Galactic Halo model. The strongest correlation is between the OVII equivalent widths and the ROSAT background emission measurement in the R45 band (0.4-1 keV), for which OVII emission makes the largest single contribution. This suggests that much of the OVII emission and absorption are cospatial, from which the radius of a uniform halo appears to lie the range 15-110 kpc. The present data do not constrain the type of halo gas model and an equally good fit is obtained in a model where the gas density decreases as a power-law, such as r^(-3/2). For a uniform halo with a radius of 20 kpc, the electron density would be 9E-4 cm^(-3), and the gas mass is 4E8 Msolar. The redshift of the four highest S/N OVII measurements is consistent with a Milky Way origin rather than a Local Group origin.Comment: 32 pages (14 figures); ApJ, in pres

Self-Consciousness and Schizophrenia: the Literary World of Nuria Amat

This article explores varieties of self-consciousness in a range of texts by the Catalan writer, Nuria Amat (1950 - ). Her relentless pursuit of interrelated themes concerning reading, writing and collecting books leads to the exploration of literary passions and mental pathologies, notably madness, as well as to literary associations with suicide and death. Amat’s references to the work of international literary figures such as Kafka, Joyce and Borges and her interest in the relevance of such concepts as originality and plagiarism in the literary domain, suggest the blurring of boundaries between creative writing and criticism which reflects the practice of several contemporary, especially Latin American, writers. The essay concludes by emphasizing the feminist aspects of Amat’s work and noting the extent of her personal involvement in the vortex of literary activities she describes, a process which approximates her style to what Felman terms a language of madness (as distinct from a language about madness)

Time, Digression and the Other (Side) in Juan Jose Saer's La grande

This essay focuses on the final novel, La grande (2005), of the Argentine writer, Juan José Saer (1937-2005) and focuses on his treatment of time in the light of the pressures posed by his impending death. It also analyses Saer’s disparagement of reason in a world governed by the pervasive influence of incoherence and discontinuity and his portraits of disability (both literal and metaphorical). Saer subordinates the intellect to the senses and literary rigour to freewheeling digressiveness. The conclusion considers the significance of the ‘lugar más grande’ that overshadows the ‘real’ world and ‘real’ time

No 'free ride' for African women:a comparison of head-loading versus back-loading among Xhosa women

Although contrasting evidence exists in the literature as to the economy of head-loading, there is a notion that head-loading is an extremely economical method of load carriage. This has become known as the ‘free ride’ hypothesis and, although untested, it is widely accepted. The purpose of this study was to test the ‘free ride’ hypothesis for head-load carriage among African women by comparing the relative economy of head-loading and back-loading. Twenty-four Xhosa women walked on a level treadmill, attempting to carry loads of between 10% and 70% of their body mass (BM) using both a backpack and a head basket. All 24 women carried at least 25% of their BM in both conditions. The relative economy of load carriage was calculated for loads of 10% to 25% of BM. Results indicated that the ‘free ride’ was not a generalisable phenomenon, with both methods realising economy scores close to unity (1.04 ± 0.19 and 0.97 ± 0.15 for head-loading and back-loading, respectively). The results did, however, reveal significant individual differences in economy scores and it is suggested that analysis of such individual differences in future may well be instructive in understanding mechanisms associated with greater economy in load carriage

A kinetic comparison of back-loading and head-loading in Xhosa women

The purpose of this study was to compare the kinetic responses associated with ground reaction force measurements to both head-loading and back-loading in a group of Xhosa women. Altogether, 16 women were divided into two groups based on their experience of head-loading. They walked over a force plate in three conditions: unloaded or carrying 20 kg in either a backpack or on their head. The most striking finding was that there was no difference in kinetic response to head-loading as a consequence of previous experience. Considering the differences between the load carriage methods, most changes were consistent with increasing load. Head-loading was, however, associated with a shorter contact time, smaller thrust maximum and greater vertical force minimum than back-loading. Both loading conditions differed from unloaded walking for a number of temporal variables associated with the ground contact phase, e.g. vertical impact peak was delayed whilst vertical thrust maximum occurred earlier. Statement of Relevance: Consideration of the kinetics of head and back load carriage in African women is important from a health and safety perspective, providing an understanding of the mechanical adaptations associated with both forms of load carriage for a group of people for whom such load carriage is a daily necessity

Subjective perceptions of load carriage on the head and back in Xhosa women

The purpose of this study was to compare the subjective perceptual responses to both head-loading and back-loading in a group of Xhosa women. Thirty two women were divided into three groups based on their experience of head-loading and walked on a treadmill on two occasions, head-loading and back-loading, at a self selected walking speed for four minutes with a variety of loads until pain or discomfort caused the test to be terminated or a load of 70% body mass was successfully carried. After each workload there was a one minute rest period during which the women indicated feelings of pain or discomfort in particular areas of the body via visual analogue scales. At the end of each test the women were asked to complete further questionnaires relating to pain and discomfort and on completion of the second test were also asked to compare the two loading conditions. Finally the women were interviewed to establish their history of load carriage and associated pain and discomfort. The data indicate that whilst back-loading was generally associated with more areas of discomfort than head-loading, the pain and discomfort in the neck associated with head-loading was the predominant factor in the termination of tests and that this was independent of head-loading experience. This early termination meant that, on average, the women could carry greater loads on their backs than on their heads. The study suggests that further work needs to be carried out to establish viable alternatives to head-loading for rural dwellers in Africa

A Comparison of the Utah Cattle Slaughter Market with the California Cattle Carcass Market

Reliable price data for fat cattle in Utah are becoming difficult to obtain because fewer and fewer slaughter cattle go through market channels where live cattle prices are reported. The objectives of this study were to determine how correlated Utah fat cattle prices are with the California dressed meat market for cattle and formulate an equation or equations enabling reliable price predictions to be made for the Utah slaughter cattle market. Utah choice and good steer prices (both direct and auction) were compared to the San Francisco wholesale meat market prices. Utah choice steer, good steer and choice heifer prices (both direct and auction) were compared with the Los Angeles wholesale meat market prices. All price comparisons were highly correlated except Utah good steer prices and Los Angeles dressed meat market prices, A regression analysis not only gave the correlation coefficients but was also used to determine any time lags between the Utah slaughter cattle market and the California dressed meat market for cattle. Price changes in the Utah slaughter cattle market are preceded by at least one weeks change in the California dressed meat market for all classifications and grades of slaughter cattle used in this study. A mathematical model was formulated which equated Utah fat cattle prices with the California dressed meat market prices. This model as well as statistical model obtained from the regression analysis if used with the time lags predict Utah fat cattle prices very satisfactorily

Process Synthesis for Antibiotic Recovery by Microfiltration from Saccharopolyspora erythraea Fermentations

The causes of the interactions between fermentation and microfiltration were first examined experimentally by investigating erythromycin production using two different media. Soluble complex media (SCM) broths reached maximum erythromycin concentrations more rapidly (64.2 0.3 h) than the less expensive and therefore industrially preferred oil based media (OBM) broths (176 15 h) but also attained lower titres (241 55 g.L-1 compared to 617 104 g.L-1). The OBM broths showed oxygen limitation due to the high apparent viscosity. Both broths were found to be shear thinning and exhibited different time dependant rheological profiles which could impact on the performance of the subsequent microfiltration operation. The microfiltration performance of the two broths was subsequently examined using a flat sheet membrane system (area = 60 - 120 cm2). This small-scale unit allowed the determination of flux and transmission profiles as a function of fermentation time and for membrane operation over a range of transmembrane pressures and crossflow velocities. The OBM broths were quicker to blind the membrane, achieved lower values of steady state permeate flux, which decreased over fermentation time as apparent viscosity increased. SCM broths showed no time dependant variation in steady state permeate flux. Transmission of product was higher in SCM (96.4 1.6 %) than OBM broths (89.6 1.4 %). This was attributed to the high solids content of the OBM broth in the form of the undissolved soya flour. The mass transfer of erythromycin across the membrane was similar in both cases (SCM: 1.47 0.28 x 10-6 kg.m-2.s-1, OBM: 1.38 0.20 x 10-6 kg.m-2.s-1) due to the differences between erythromycin titre and permeate flux. For the SCM broths image analysis was also used to determine if there was a relationship between bacterial morphology and microfiltration performance. No such relationship could be adequately determined. In OBM broths image analysis was used to predict the biomass concentration. Modelling of the process using on- and off-line measurements, combined with scale-down methodologies, allows unit operations to be rapidly assessed and optimised, thus reducing product lead times through the development process. The performance of the microfiltration step was successfully predicted using a simple gel polarisation model which was reliable within a fermentation 9.5 % and a model modified to take account of operation at pressure below cTMP 6.2%. This allowed prediction of steady state permeate flux at the harvest time and the critical transmembrane pressure

Studies on times of lambing in ewes grazing subterranean clover based pastures in relation to stocking rates in south-western Australia

The investigation is reported in six parts: effect on ewe liveweight and fertility, lamb losses, effect on lamb growth and subsequent growth after weaning, wool production, pasture production and composition, and conclusions and practical implications. The results show that in the absence of supplementary feeding the physiological requirements of ewes in late pregnancy are better met by spring rather than autumn lambing