Quantifying mixing using magnetic resonance imaging.

Mixing is a unit operation that combines two or more components into a homogeneous mixture. This work involves mixing two viscous liquid streams using an in-line static mixer. The mixer is a split-and-recombine design that employs shear and extensional flow to increase the interfacial contact between the components. A prototype split-and-recombine (SAR) mixer was constructed by aligning a series of thin laser-cut Poly (methyl methacrylate) (PMMA) plates held in place in a PVC pipe. Mixing in this device is illustrated in the photograph in Fig. 1. Red dye was added to a portion of the test fluid and used as the minor component being mixed into the major (undyed) component. At the inlet of the mixer, the injected layer of tracer fluid is split into two layers as it flows through the mixing section. On each subsequent mixing section, the number of horizontal layers is duplicated. Ultimately, the single stream of dye is uniformly dispersed throughout the cross section of the device. Using a non-Newtonian test fluid of 0.2% Carbopol and a doped tracer fluid of similar composition, mixing in the unit is visualized using magnetic resonance imaging (MRI). MRI is a very powerful experimental probe of molecular chemical and physical environment as well as sample structure on the length scales from microns to centimeters. This sensitivity has resulted in broad application of these techniques to characterize physical, chemical and/or biological properties of materials ranging from humans to foods to porous media (1, 2). The equipment and conditions used here are suitable for imaging liquids containing substantial amounts of NMR mobile (1)H such as ordinary water and organic liquids including oils. Traditionally MRI has utilized super conducting magnets which are not suitable for industrial environments and not portable within a laboratory (Fig. 2). Recent advances in magnet technology have permitted the construction of large volume industrially compatible magnets suitable for imaging process flows. Here, MRI provides spatially resolved component concentrations at different axial locations during the mixing process. This work documents real-time mixing of highly viscous fluids via distributive mixing with an application to personal care products

Haemopoietic progenitor-cell responses in mice with the transplanted lymphoid leukaemia ABE-8.

BALB/c mice bearing the transplanted lymphoid tumour ABE-8 developed increased levels of neutrophil, macrophage and eosinophil progenitor cells in the marrow and spleen. Neutrophil-macrophage progenitors, assayed as granulocyte-macrophage colony-forming cells in agar, increased in number only if invasion of the marrow or spleen by ABE-8 cells was demonstrable. Rises in B-lymphocyte colony-forming cells occurred whether or not there was invasion of the host spleen or marrow. No increase in progenitor cells was found in mice bearing diffusion chambers containing ABE-8 cells. The magnitude of leukaemic infiltration was determined by assaying numbers of leukaemic stem cells in the spleen and marrow using a selective cloning system. This transplanted lymphoid leukaemia appears to be a useful model for analysing the effects of haemopoietic tumours on host haemopoietic tissues

Aribo, De musica and Sententiae

Music was central to the medieval church\u27s public worship: it was the essential medium of the Mass and the Divine Office. In this new critical edition, T. J. H. McCarthy presents the Latin text and the first English translation of Aribo\u27s musical treatise, De musica and Sententiae. Written between 1070 and 1078, it is concerned with the workings of the liturgical music that Aribo and his contemporaries called Gregorian chant, and builds off of and responds to several contemporary treatises by Abbot Bern of Reichenau and his pupil Herman, Abbot William of Hirsau, Frutolf of Michelsberg, and Theoger of Metz. In the first new edition of the treatise in over sixty years, McCarthy addresses not only new approaches to the study of music history but newly discovered manuscripts of the treatise, paying careful attention to the diagrams that are integral to the coherence of the treatise.https://scholarworks.wmich.edu/mip_teamsvaria/1005/thumbnail.jp

Clustering of equine grass sickness cases in the United Kingdom: a study considering the effect of position-dependent reporting on the space-time K-function

Equine grass sickness (EGS) is a largely fatal, pasture-associated dysautonomia. Although the aetiology of this disease is unknown, there is increasing evidence that Clostridium botulinum type C plays an important role in this condition. The disease is widespread in the United Kingdom, with the highest incidence believed to occur in Scotland. EGS also shows strong seasonal variation (most cases are reported between April and July). Data from histologically confirmed cases of EGS from England and Wales in 1999 and 2000 were collected from UK veterinary diagnostic centres. The data did not represent a complete census of cases, and the proportion of all cases reported to the centres would have varied in space and, independently, in time. We consider the variable reporting of this condition and the appropriateness of the space–time K-function when exploring the spatial-temporal properties of a ‘thinned’ point process. We conclude that such position-dependent under-reporting of EGS does not invalidate the Monte Carlo test for space–time interaction, and find strong evidence for space–time clustering of EGS cases (P<0.001). This may be attributed to contagious or other spatially and temporally localized processes such as local climate and/or pasture management practices

Deep VLT spectroscopy of the z=2.49 Radio Galaxy MRC 2104-242: Evidence for a metallicity gradient in its extended emission line region

We present spectroscopic observations of the rest-frame UV line emission around radio galaxy MRC 2104-242 at z=2.49, obtained with FORS1 on VLT Antu. The morphology of the halo is dominated by two spatially resolved regions. Lya is extended by >12 arcsec along the radio axis, CIV and HeII are extended by ~8 arcsec. The overall spectrum is typical for that of high redshift radio galaxies. The most striking spatial variation is that NV is present in the spectrum of the region associated with the center of the galaxy hosting the radio source, the northern region, while absent in the southern region. Assuming that the gas is photoionized by a hidden quasar, the difference in NV emission can be explained by a metallicity gradient within the halo. This is consistent with a scenario in which the gas is associated with a massive cooling flow or originates from the debris of the merging of two or more galaxies.Comment: Accepted for publication in A&A Letter

HST images and properties of the most distant radio galaxies

We present Hubble Space Telescope images of 11 high redshift radio galaxies (between $z=2.3$ and $z=3.6$). The galaxies were observed with the WFPC2 camera in a broad band filter (F606W or F707W, roughly equivalent to V or R-band), for 2 orbits each. We find that on the scale of the HST observations there is a wide variety of morphological structures of the hosting galaxies: most objects have a clumpy, irregular appearance, consisting of a bright nucleus and a number of smaller components, suggestive of merging systems. Some observed structures could be due (at least partly) to the presence of dust distributed through the galaxies. The UV continuum emission is generally elongated and aligned with the axis of the radio sources, however the characteristics of the ``alignment effect'' differ from case to case, suggesting that the phenomenon cannot be explained by a single physical mechanism. We compare the properties of our radio galaxies with those of the UV dropout galaxies and conclude that (i) the most massive radio galaxies may well evolve from an aggregate of UV dropout galaxies and (ii) high redshift radio galaxies probably evolve into present day brightest cluster galaxies.Comment: 22 pages, 30 figures, accepted by A&

A new dawn? The Roman Catholic Church and environmental issues

This is a PDF version of an article published in New Blackfriars© 1997. The definitive version is available at www.blackwell-synergy.com.This article discusses the stance of the Roman Catholic Church on environmental issues and argues that the Church tends to stay on the fringe rather than get involved. Some of the ways in which Roman Catholic theologians have incorporated environmental issues into theological reflection is discussed, as are environmental challenges facing the Church in Britain (conservation, resources, biodiversity, animal welfare, biotechnology, cooperate/individual ethics, environmental justice, economics/policy development, and global issues)

Investigating Heating and Cooling in the BCS & B55 Cluster Samples

We study clusters in the BCS cluster sample which are observed by Chandra and are more distant than redshift, z>0.1. We select from this subsample the clusters which have both a short central cooling time and a central temperature drop, and also those with a central radio source. Six of the clusters have clear bubbles near the centre. We calculate the heating by these bubbles and express it as the ratio r_heat/r_cool=1.34+/-0.20. This result is used to calculate the average size of bubbles expected in all clusters with central radio sources. In three cases the predicted bubble sizes approximately match the observed radio lobe dimensions. We combine this cluster sample with the B55 sample studied in earlier work to increase the total sample size and redshift range. This extended sample contains 71 clusters in the redshift range 0<z<0.4. The average distance out to which the bubbles offset the X-ray cooling in the combined sample is at least r_heat/r_cool=0.92+/-0.11. The distribution of central cooling times for the combined sample shows no clusters with clear bubbles and t_cool>1.2Gyr. An investigation of the evolution of cluster parameters within the redshift range of the combined samples does not show any clear variation with redshift.Comment: 12 pages, 9 figures, accepted for publication in MNRA

A new era for The Sea

Author Posting. © The Authors, 2017. This article is posted here by permission of Sears Foundation for Marine Research for personal use, not for redistribution. The definitive version was published in Journal of Marine Research 75 (2017): 99, doi:10.1357/002224017821836815