Moisture movement in bulk stockpiles

Both drainage and evaporation are possible mechanisms for moisture loss in iron-ore and coal stockpiles. Some simple models are used to study both these mechanisms for various stages of stockpiling. The process of segregation of different particle sizes of the ore as it is stockpiled is also considered and this may have important implications for both drainage and evaporative moisture loss

Tear film thickness variations and the role of the tear meniscus

A mathematical model is developed to investigate the two-dimensional variations in the thickness of tear fluid deposited on the eye surface during a blink. Such variations can become greatly enhanced as the tears evaporate during the interblink period.\ud The four mechanisms considered are: i) the deposition of the tear film from the upper eyelid meniscus, ii) the flow of tear fluid from under the eyelid as it is retracted and from the lacrimal gland, iii) the flow of tear fluid around the eye within the meniscus and iv) the drainage of tear fluid into the canaliculi through the inferior and superior puncta.\ud There are two main insights from the modelling. First is that the amount of fluid within the tear meniscus is much greater than previously employed in models and this significantly changes the predicted distribution of tears. Secondly the uniformity of the tear film for a single blink is: i) primarily dictated by the storage in the meniscus, ii) quite sensitive to the speed of the blink and the ratio of the viscosity to the surface tension iii) less sensitive to the precise puncta behaviour, the flow under the eyelids or the specific distribution of fluid along the meniscus at the start of the blink. The modelling briefly examines the flow into the puncta which interact strongly with the meniscus and acts to control the meniscus volume. In addition it considers flow from the lacrimal glands which appears to occurs continue even during the interblink period when the eyelids are stationary

The 2MASS Wide-Field T Dwarf Search. IV Unting out T dwarfs with Methane Imaging

We present first results from a major program of methane filter photometry for low-mass stars and brown dwarfs. The definition of a new methane filter photometric system is described. A recipe is provided for the differential calibration of methane imaging data using existing 2MASS photometry. We show that these filters are effective in discriminating T dwarfs from other types of stars, and demonstrate this with Anglo-Australian Telescope observations using the IRIS2 imager. Methane imaging data and proper motions are presented for ten T dwarfs identified as part of the 2MASS "Wide Field T Dwarf Search" -- seven of them initially identified as T dwarfs using methane imaging. We also present near-infrared moderate resolution spectra for five T dwarfs, newly discovered by this technique. Spectral types obtained from these spectra are compared to those derived from both our methane filter observations, and spectral types derived by other observers. Finally, we suggest a range of future programs to which these filters are clearly well suited: the winnowing of T dwarf and Y dwarf candidate objects coming from the next generation of near-infrared sky surveys; the robust detection of candidate planetary-mass brown dwarfs in clusters; the detection of T dwarf companions to known L and T dwarfs via deep methane imaging; and the search for rotationally-modulated time-variable surface features on cool brown dwarfs.Comment: 20 pages. To appear in The Astronomical Journal, Nov. 200

High dose melphalan, BCNU and etoposide with autologous bone marrow transplantation for Hodgkin's disease.

Thirty-eight patients with previously treated Hodgkin's disease were given high dose combination chemotherapy using melphalan and BCNU and autologous bone marrow transplantation. In 25 patients etoposide was added in conventional dosage. During the course of the study the dose of melphalan was increased from 80 to 140 mg m-2 and the dose of BCNU from 300 to 600 mg m-2. The response rate was 76% with 53% complete remission. Forty-five per cent of the patients are free of disease at 4-20 months follow-up. There were eight (26%) treatment-related deaths due to lung damage (seven cases) and irreversible cardiac failure (one case). Fatal lung damage occurred only in patients receiving 600 mg m-2 of BCNU with high dose melphalan. The dose of BCNU given with high dose melphalan should not exceed 500 mg m-2. This treatment is effective against relapsed Hodgkin's disease but must be used cautiously. The best time for its use remains to be determined

Quiescience as a mechanism for cyclical hypoxia and acidosis

Tumour tissue characteristically experiences fluctuations in substrate supply. This unstable microenvironment drives constitutive metabolic changes within cellular populations and, ultimately, leads to a more aggressive phenotype. Previously, variations in substrate levels were assumed to occur through oscillations in the hæmodynamics of nearby and distant blood vessels. In this paper we examine an alternative hypothesis, that cycles of metabolite concentrations are also driven by cycles of cellular quiescence and proliferation. Using a mathematical modelling approach, we show that the interdependence between cell cycle and the microenvironment will induce typical cycles with the period of order hours in tumour acidity and oxygenation. As a corollary, this means that the standard assumption of metabolites entering diffusive equilibrium around the tumour is not valid; instead temporal dynamics must be considered

Magnetometry of the classical T Tauri star GQ Lup: non-stationary dynamos & spin evolution of young Suns

We report here results of spectropolarimetric observations of the classical T Tauri star (cTTS) GQ Lup carried out with ESPaDOnS at the Canada-France-Hawaii Telescope (CFHT) in the framework of the "Magnetic Protostars and Planets" (MaPP) programme, and obtained at 2 different epochs (2009 July & 2011 June). From these observations, we first infer that GQ Lup has a photospheric temperature of 4,300+-50\^A K and a rotation period of 8.4+-0.3 d; it implies that it is a 1.05+-0.07 Msun star viewed at an inclination of ~30deg, with an age of 2-5 Myr, a radius of 1.7+-0.2 Rsun, and has just started to develop a radiative core. Large Zeeman signatures are clearly detected at all times, both in photospheric lines & in accretion-powered emission lines, probing longitudinal fields of up to 6 kG and hence making GQ Lup the cTTS with the strongest large-scale fields known as of today. Rotational modulation of Zeeman signatures is clearly different between our 2 runs, demonstrating that large-scale fields of cTTSs are evolving with time and are likely produced by non-stationary dynamo processes. Using tomographic imaging, we reconstruct maps of the large-scale field, of the photospheric brightness & of the accretion-powered emission of GQ Lup. We find that the magnetic topology is mostly poloidal & axisymmetric; moreover, the octupolar component of the large-scale field (of strength 2.4 & 1.6 kG in 2009 & 2011) dominates the dipolar component (of strength ~1 kG) by a factor of ~2, consistent with the fact that GQ Lup is no longer fully-convective. GQ Lup also features dominantly poleward magnetospheric accretion at both epochs. The large-scale dipole of GQ Lup is however not strong enough to disrupt the surrounding accretion disc further than about half-way to the corotation radius, suggesting that GQ Lup should rapidly spin up like other similar partly-convective cTTSs (abridged).Comment: MNRAS, in press (17 pages, 10 figures, 1 table