No abstract

The OSIMIS (OSI Management Information Service) platform provides the foundation for the quick, efficient and easy construction of complex management systems. It is an object-oriented development environment in C++ [Strou] based on the OSI Management Model [X701] that hides the underlying protocol complexity (CMIS/P) and harnesses the power and expressiveness of the associated information model [X722] through simple to use Application Program Interfaces (APIs). OSIMIS combines the thoroughness of the OSI models and protocols with advanced distributed systems concepts pioneered by ODP to provide a highly dynamic distributed information store. It also combines seamlessly the OSI management power with the large installed base of Internet SNMP [SNMP] capable network elements. OSIMIS supports particularly well a hierarchical management organisation through hybrid manager-agent applications and may embrace a number of diverse technologies through proxy systems. This paper explains the OSIMIS components, architecture, philosophy and direction.

The immunoglobulin heavy chain enhancer, or enhancer, is required for B cell development. Only the appropriate combination of transcription factors results in B cell-specific enhancer activation. HMGA1 (formerly (HMG-I(Y)) is a proposed co-activator of the ETS transcription factors required for enhancer activity. HMGA1 associates with the ETS factor PU.1, resulting in changes in PU.1 structure, and enhanced transcriptional synergy with Ets-1 on the enhancer in nonlymphoid cells. New data show HMGA1 directly interacts with Ets-1 in addition to PU.1. In vitro HMGA1/Ets-1 interaction facilitates Ets-1/ enhancer binding in the absence of an HMGA1⅐Ets-1⅐DNA complex. To address whether HMGA1 is present in the transcriptionally active nucleoprotein complex, we completed DNA pulldown assays to detect protein tethering in the context of protein/DNA interaction. Results show that HMGA1 is not tightly associated with enhancer DNA through PU.1 or Ets-1, despite strong associations between these proteins in solution. However, chromatin immunoprecipitation assays show HMGA1 associates with the endogenous enhancer in B cells. Furthermore, antisense HMGA1 substantially decreases enhancer activity in B cells. Taken together, these data suggest that HMGA1 functions as a transcriptional enhancer co-activator in B cells through indirect association with DNA.

Changes in tropical width can have important consequences in sectors including ecosystems, agriculture, and health. Observations suggest tropical expansion over the past 30 years although studies have not agreed on the magnitude of this change. Climate model projections have also indicated an expansion and show similar uncertainty in its magnitude. This study utilizes an objective, longitudinally varying, tropopause break method to define the extent of the tropics at upper levels. The location of the tropopause break is associated with enhanced stratosphere-troposphere exchange and thus its structure influences the chemical composition of the stratosphere. The method shows regional variations in the width of the upper-level tropics in the past and future. Four modern reanalyses show significant contraction of the tropics over the eastern Pacific between 1981 and 2015, and slight but significant expansion in other regions. The east Pacific narrowing contributes to zonal mean narrowing, contradicting prior work, and is attributed to the use of monthly and zonal mean data in prior studies. Six global climate models perform well in representing the climatological location of the tropical boundary. Future projections show a spread in the width trend (from ;0.58 decade 21 of narrowing to ;0.48 decade 21 of widening), with a narrowing projected across the east Pacific and Northern Hemisphere Americas. This study illustrates that this objective tropopause break method that uses instantaneous data and does not require zonal averaging is appropriate for identifying upper-level tropical width trends and the break location is connected with local and regional changes in precipitation.

The neonatal Fc receptor, FcRn, transports immunoglobulin G (IgG) across cellular barriers between mother and offspring. FcRn also protects circulating IgG from catabolism, probably during transport across the capillary endothelium. Only one cell culture model of transcytosis has been used extensively, the transport of IgA from the basolateral to the apical surface of Madin-Darby canine kidney cells by the polymeric immunoglobulin receptor (pIgR). We report that rat inner medullary collecting duct (IMCD) cells transfected with DNA encoding the (alpha) subunit of rat FcRn specifically and saturably transport Fc when grown as polarized monolayers. Using this system, we have found that transcytosis by FcRn, like transcytosis by the pIgR, depends upon an intact microtubule system. FcRn differs most strikingly from the pIgR in its ability to transport its ligand in both the apical to basolateral and basolateral to apical directions. The phosphatidylinositol 3-kinase inhibitors wortmannin and LY294002 inhibited basolateral to apical transport by FcRn more than apical to basolateral transport, suggesting that there are differences in the mechanisms of transport in the two directions. Lastly, we found that transcytosis by FcRn depends upon vesicular acidification. We anticipate that the IMCD cell culture model will allow further elucidation of the mechanism of IgG transport by FcRn.