From the Top to the Bottom of the Main Sequence: A Complete Mass Function of the Young Open Cluster M35

We present very deep and accurate photometry of the open cluster M35 (VRIc filters). We have covered a region of 27.5x27.5 square arcmin. The data range from Ic=12.5 to 23.5 mag, and the color intervals are 0.4\le(V-I)c\le3.0, 0.5\le(R-I)c\le2.5. Roughly, these values span from 1.6 M_\odot down to the substellar limit. By using the location of the stars on color-magnitude and color-color diagrams, we have selected candidate members of this cluster. We have merged our sample with previously published data and obtained a color-magnitude diagram for the complete stellar population of the cluster, covering the spectral range early B - mid M. The Mass Function increases monotonically, when plotted in a log-log form, until it reaches ~0.8 M_\odot (\alpha=2.59). It remains shallower for less massive stars (\alpha=0.81 for 0.8-0.2 M_\odot), whereas a decrease ins observed for stars close to the substellar regime. The total mass of the cluster is ~1600 M_\odot in the area covered by this study.Comment: Accepted ApJ (Jan 10, 2001 issue

The Retinoic Acid Receptor Agonist Am80 Increases Mucosal Inflammation in an IL-6 Dependent Manner During Trichuris muris Infection

PURPOSE: Vitamin A metabolites, such as all-trans-retinoic acid (RA) that act through the nuclear receptor; retinoic acid receptor (RAR), have been shown to polarise T cells towards Th2, and to be important in resistance to helminth infections. Co-incidentally, people harbouring intestinal parasites are often supplemented with vitamin A, as both vitamin A deficiency and parasite infections often occur in the same regions of the globe. However, the impact of vitamin A supplementation on gut inflammation caused by intestinal parasites is not yet completely understood. METHODS: Here, we use Trichuris muris, a helminth parasite that buries into the large intestine of mice causing mucosal inflammation, as a model of both human Trichuriasis and IBD, treat with an RARα/β agonist (Am80) and quantify the ensuing pathological changes in the gut. RESULTS: Critically, we show, for the first time, that rather than playing an anti-inflammatory role, Am80 actually exacerbates helminth-driven inflammation, demonstrated by an increased colonic crypt length and a significant CD4(+) T cell infiltrate. Further, we established that the Am80-driven crypt hyperplasia and CD4(+) T cell infiltrate were dependent on IL-6, as both were absent in Am80-treated IL-6 knock-out mice. CONCLUSIONS: This study presents novel data showing a pro-inflammatory role of RAR ligands in T. muris infection, and implies an undesirable effect for the administration of vitamin A during chronic helminth infection. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10875-013-9936-8) contains supplementary material, which is available to authorized users

Islamic architecture

New York424 p.: Illus., 28 cm

Western Islamic Architecture

vii, 120 hlm.;20c