1,028 research outputs found

    Bridging the Semantic Gap in Multimedia Information Retrieval: Top-down and Bottom-up approaches

    No full text
    Semantic representation of multimedia information is vital for enabling the kind of multimedia search capabilities that professional searchers require. Manual annotation is often not possible because of the shear scale of the multimedia information that needs indexing. This paper explores the ways in which we are using both top-down, ontologically driven approaches and bottom-up, automatic-annotation approaches to provide retrieval facilities to users. We also discuss many of the current techniques that we are investigating to combine these top-down and bottom-up approaches

    Amino-terminal cysteine residues of RGS16 are required for palmitoylation and modulation of G(i)- and G(q)-mediated signaling

    Get PDF
    RGS proteins (Regulators of G protein Signaling) are a recently discovered family of proteins that accelerate the GTPase activity of heterotrimeric G protein Ī± subunits of the i, q, and 12 classes. The proteins share a homologous core domain but have divergent amino-terminal sequences that are the site of palmitoylation for RGS-GAIP and RGS4. We investigated the function of palmitoylation for RGS16, which shares conserved amino-terminal cysteines with RGS4 and RGS5. Mutation of cysteine residues at residues 2 and 12 blocked the incorporation of [3H]palmitate into RGS16 in metabolic labeling studies of transfected cells or into purified RGS proteins in a cell-free palmitoylation assay. The purified RGS16 proteins with the cysteine mutations were still able to act as GTPase-activating protein for GiĪ±. Inhibition or a decrease in palmitoylation did not significantly change the amount of protein that was membrane-associated. However, palmitoylation-defective RGS16 mutants demonstrated impaired ability to inhibit both Gi- and Gq-linked signaling pathways when expressed in HEK293T cells. These findings suggest that the amino-terminal region of RGS16 may affect the affinity of these proteins for GĪ± subunits in vivo or that palmitoylation localizes the RGS protein in close proximity to GĪ± subunits on cellular membranes

    Implementing Intensive Family Preservation Services: A Case of Infidelity

    Get PDF
    The importance of treatment fidelity in evaluations of all human service programs, including intensive family preservation services (IFPS), is examined in this article. Special attention is focused on the issue of treatment fidelity in IFPS programs attempting to adhere to a specific program model (HomebuildersĀ©), and on the problems that lack of treatment fidelity has caused for research that has been conducted on this and other program models. Attempts to address the issue of treatment fidelity in other program areas offer models for constructing treatment fidelity assessment tools for IFPS. The authors suggest a schema for assessing treatment fidelity in evaluations of IFPS programs that should help to explore relationships among different approaches to IFPS, the consistency with which they are being implemented, and the outcomes that result

    Selective migration of neuralized embryonic stem cells to stem cell factor and media conditioned by glioma cell lines

    Get PDF
    BACKGROUND: Pluripotent mouse embryonic stem (ES) cells can be induced in vitro to become neural progenitors. Upon transplantation, neural progenitors migrate toward areas of damage and inflammation in the CNS. We tested whether undifferentiated and neuralized mouse ES cells migrate toward media conditioned by glioma cell lines (C6, U87 & N1321) or Stem Cell Factor (SCF). RESULTS: Cell migration assays revealed selective migration by neuralized ES cells to conditioned media as well as to synthetic SCF. Migration of undifferentiated ES cells was extensive, but not significantly different from that of controls (Unconditioned Medium). RT-PCR analysis revealed that all the three tumor cell lines tested synthesized SCF and that both undifferentiated and neuralized ES cells expressed c-kit, the receptor for SCF. CONCLUSION: Our results demonstrate that undifferentiated ES cells are highly mobile and that neural progenitors derived from ES cells are selectively attracted toward factors produced by gliomas. Given that the glioma cell lines synthesize SCF, SCF may be one of several factors that contribute to the selective migration observed

    The effects of cystoscopy and hydrodistention on symptoms and bladder capacity in interstitial cystitis/bladder pain syndrome

    Full text link
    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145499/1/nau23555_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145499/2/nau23555.pd

    A variational problem on Stiefel manifolds

    Full text link
    In their paper on discrete analogues of some classical systems such as the rigid body and the geodesic flow on an ellipsoid, Moser and Veselov introduced their analysis in the general context of flows on Stiefel manifolds. We consider here a general class of continuous time, quadratic cost, optimal control problems on Stiefel manifolds, which in the extreme dimensions again yield these classical physical geodesic flows. We have already shown that this optimal control setting gives a new symmetric representation of the rigid body flow and in this paper we extend this representation to the geodesic flow on the ellipsoid and the more general Stiefel manifold case. The metric we choose on the Stiefel manifolds is the same as that used in the symmetric representation of the rigid body flow and that used by Moser and Veselov. In the extreme cases of the ellipsoid and the rigid body, the geodesic flows are known to be integrable. We obtain the extremal flows using both variational and optimal control approaches and elucidate the structure of the flows on general Stiefel manifolds.Comment: 30 page
    • ā€¦
    corecore