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Ultra-high-pressure (UHP) eclogites and ultramafites and associated fluid inclusions from the Western Gneiss Region, Norwegian Caledonides, have been analysed for F, Cl, Br and I using electron-probe micro-analysis, time-of-flight secondary ion mass spectrometry and neutron-irradiated noble gas mass spectrometry. Textures of multi-phase and fluid inclusions in the cores of silicate grains indicate formation during growth of the host crystal at UHP. Halogens are predominantly hosted by fluid inclusions with a minor component from mineral inclusions such as biotite, phengite, amphibole and apatite. The reconstructed fluid composition contains between 11.3 and 12.1 wt% Cl, 870 and 8900 ppm Br and 6 and 169 ppm I. F/Cl ratios indicate efficient fractionation of F from Cl by hydrous mineral crystallisation. Heavy halogen ratios are higher than modern seawater by up to two orders of magnitude for Br/Cl and up to three orders of magnitude for I/Cl. No correlation exists between Cl and Br or I, while Br and I show good correlation, suggesting that Cl behaved differently to Br and I during subduction. Evolution to higher Br/Cl ratios is similar to trends defined by eclogitic hydration reactions and seawater evaporation, indicating preferential removal of Cl from the fluid during UHP metamorphism. This study, by analogy, offers a field model for an alternative source (continental crust) and mechanism (metasomatism by partial melts or supercritical fluids) by which halogens may be transferred to and stored in the sub-continental lithospheric mantle during transient subduction of a continental margin.

Background. DNA adenine methyltransferase (dam) has been well documented for its role in regulation of replication, mismatch repair and transposition. Recent studies have also suggested a role for dam in protection against antibiotic stress, although this is not yet fully defined. We therefore evaluated the role of dam in the development of antibiotic resistance and triclosan-associated cross-resistance. Results. A significant impact on growth rate was seen in the dam knockout compared to the parental strain. Known triclosan resistance-associated mutations in fabI were seen regardless of dam status, with an additional mutation in lrhA seen in the dam knockout. The expression of multiple antibiotic resistance-associated genes was significantly different between the parent and dam knockout post-resistance induction. Reversion rate assays showed that resistance mechanisms were stable. Conclusions. dam knockout had a significant effect on growth, but its role in the development of antibiotic resistance is likely confined to those antibiotics using acrAD-containing efflux pumps.

Phase equilibrium experiments were performed in the MgO–SiO2–H2O system, along with fluorine (MSH + F), at conditions between 800–1000 °C and 2.0–2.5 GPa to constrain the solubility of fluorine in humite-group minerals and to determine fluorine partitioning between humite-group minerals and aqueous fluid. Fluorine solubility in humite-group minerals ranges between ~ 1 and 11 wt% F and is dependent on the salinity of the fluid (~ 0.2–3.5 wt% F), indicating that humite-group minerals have exceedingly high saturation limits for F and that a full solid solution between F− and OH− is possible within the crystal structure. Raman spectroscopy reveals the preferential ordering of F, promoting the formation of a stable OH–F bond. Mineral-fluid partition coefficients are always greater than unity, with average coefficients of D F clinohumite/fluid = 3, D F humite/fluid = 2, D F chondrodite/fluid = 4, and D F norbergite/fluid = 4. Partition coefficients are independent of pressure or temperature, but decrease with increasing fluid salinity. Fluorine is, therefore, highly soluble and compatible within this group of ultramafic mantle minerals. High solubility and mineral-fluid partition coefficients, together with wide stability fields in pressure and temperature space, demonstrate that humite-group minerals are potential storage sites for F, and by extension H2O, during subduction. Upon the breakdown of less stable hydrous and/or fluorine-rich phases during lower grades of subduction zone metamorphism, fluorine may redistribute into phases such as humite-group minerals and be transported beyond the volcanic arc and to the upper mantle.

During the course of rodent malaria a marked decrease in the numbers of circulating lymphocytes within the peripheral blood occurred 2-4 days post-infection. Monocytes and polymorphs did not show the same degree of decline. For both avirulent Plasmodium yoelii and lethal Plasmodium berghei infections lymphocyte numbers returned to control levels by day 6-8 post-infection. While these levels were maintained until clearance of P. yoelii infection, a sustained and abnormal increase occurred during P. berghei infection. Early lymphocyte depletion was also observed following Babesia microti and Plasmodium vinckei petteri infections, and could be induced by freeze-thawed P. yoelii infected blood and its particulate, but not soluble, fraction. Corynebacterium parvum and sheep red blood cells had no depressant effect on peripheral blood lymphocyte counts. Cell trapping experiments indicated that peripheral blood lymphocytes were preferentially recruited to the spleen in the initial stages of infection. Cell surface marker tests showed that the major cell type involved was Thy-1.2+ T-lymphocytes.

The protection of mouse erythrocytes (RBC) parasitized with Plasmodium vinckei vinckei against activated oxygen species was examined in relation to the intraerythrocytic parasite load. RBC from highly infected animals were separated by density gradient centrifugation into six bands with increasing parasite content and with parasitemias ranging from 17% to 100%. Increase in parasite load was accompanied by a decrease in the activities of the enzymes superoxide dismutase (EC 1.15.1.1), catalase (EC 1.11.1.6), glutathione peroxidase (EC 1.11.1.9), glutathione reductase [NAD(P)H] (EC 1.6.4.2), and NADH-methemoglobin reductase (EC 1.6.2.2; NADH:ferricytochrome b5 oxidoreductase) in the RBC lysates. In contrast, the total amount of reduced glutathione increased in the highly parasitized bands. Furthermore, the vitamin E content of all RBC bands, including the one that contained mainly nonparasitized erythrocytes, was 3- to 5-fold higher than that of control noninfected RBC. Increasing parasite load was accompanied by an increase in the production of malonyldialdehyde, indicating enhanced lipid peroxidation. Our results indicate that oxidative stress is experienced by all RBC during a malarial infection and is accompanied by a variety of changes in the antioxidant defense mechanisms of the host and the parasite. Furthermore, it appears that the plasma membrane of the host cell is better protected against oxidative injury than are the membranes surrounding the parasite.

During the course of rodent malaria a marked decrease in the numbers of circulating lymphocytes within the peripheral blood occurred 2-4 days post-infection. Monocytes and polymorphs did not show the same degree of decline. For both avirulent Plasmodium yoelii and lethal Plasmodium berghei infections lym- phocyte numbers returned to control levels by day 6-8 post-infection. While these levels were maintained until clearance of P. yoelii infection, a sustained and abnormal increase occurred during P. berghei infection. Early lymphocyte depletion was also observed following Babesia microti and Plasmodium vinckei petteri infections, and could be induced by freeze-thawed P. yoelii infected blood and its particulate, but not soluble, fraction. Corynebacterium parvum and sheep red blood cells had no depressant effect on peripheral blood lymphocyte counts. Cell trapping experiments indicated that peripheral blood lymphocytes were preferentially recruited to the spleen in the initial stages of infection. Cell surface marker tests showed that the major cell type involved was Thy-l .2+ T-lymphocytes.

The small tract here reprinted, A plaine and true relation of the goodnes of God towards the Sommer Hands, written by way of exhortation, to stirre up the people there to praise God, was first printed at London by Edward All-de in 1621. Its author was Lewis Hughes, Puritan minister in the colony of Bermuda. As published, it occupied the first fifteen of forty-six pages of text in a small quarto of twenty-four unnumbered leaves. The remainder of the pamphlet, except for a little over three pages at the end devoted to suggested prayers, was comprised of Certaine questions and answers concerning the keeping holy of the Saboth day, and publicke exercises of religion: written in the Summer Ilands for the benefit of the people there.' This "doctrine of the Saboth," as the author commonly referred to it, was also a product of Hughes' pen. Thus, it will be seen, the "Relation," exhortatory in spirit and historical in form, served as an introduction to the more lengthy Sabbatarian treatise. Of the two, Hughes regarded the latter as of greater importance, and for reasons not difficult to understand. But historians find more worth in the other, to which several considerations lend unusual interest.2