237 research outputs found
Effectiveness of segment routing technology in reducing the bandwidth and cloud resources provisioning times in network function virtualization architectures
Network Function Virtualization is a new technology allowing for a elastic cloud and bandwidth resource allocation. The technology requires an orchestrator whose role is the service and resource orchestration. It receives service requests, each one characterized by a Service Function Chain, which is a set of service functions to be executed according to a given order. It implements an algorithm for deciding where both to allocate the cloud and bandwidth resources and to route the SFCs. In a traditional orchestration algorithm, the orchestrator has a detailed knowledge of the cloud and network infrastructures and that can lead to high computational complexity of the SFC Routing and Cloud and Bandwidth resource Allocation (SRCBA) algorithm. In this paper, we propose and evaluate the effectiveness of a scalable orchestration architecture inherited by the one proposed within the European Telecommunications Standards Institute (ETSI) and based on the functional separation of an NFV orchestrator in Resource Orchestrator (RO) and Network Service Orchestrator (NSO). Each cloud domain is equipped with an RO whose task is to provide a simple and abstract representation of the cloud infrastructure. These representations are notified of the NSO that can apply a simplified and less complex SRCBA algorithm. In addition, we show how the segment routing technology can help to simplify the SFC routing by means of an effective addressing of the service functions. The scalable orchestration solution has been investigated and compared to the one of a traditional orchestrator in some network scenarios and varying the number of cloud domains. We have verified that the execution time of the SRCBA algorithm can be drastically reduced without degrading the performance in terms of cloud and bandwidth resource costs
Insight on collagen self-assembly mechanisms by coupling molecular dynamics and UV spectroscopy techniques
Self-assembly of rat tail collagen type I was investigated by means of turbidity measurements and molecular dynamics simulations. Turbidity curves collected at different pH values show that the rate of aggregation was not linear in dependence from pH, with the fastest kinetics at pHâŻ5.0 and the lowest at neutral pH. MD simulations were carried out on two regions with different hydropathicity, monitoring the aggregation of up to four staggered tropocollagen fragments at different ionic strength. At physiological conditions, association of lowly charged regions occurs more easily than for highly charged ones, the latter seeming to aggregate in a sequential way. The first contacts indicate for both regions that the driving force is hydrophobic, the electrostatic contribution becoming relevant at short distance. The direct inter-tropocollagen H-bonds confirm that fibrillogenesis is driven by loss of surface water from the monomers and involves in large percentage hydroxyproline residues. Low ionic strength dynamics leads to the formation of incorrect assemblies, driven by not shielded pairwise charge interactions
Creation of a Scholars Program in Dental Leadership (SPDL) for Dental and Dental Hygiene Students
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153552/1/jddj0022033720097310tb04805x.pd
Dynamic in-network classification for service function chaining ready SDN networks
Service Function Chaining (SFC) paradigm consists in steering traffic flows through an ordered set of Service Functions (SFs) so that to realize complex end to end services. SFC architecture introduces all the logical functions that need to be developed in order to provide the required service. The SFC overlay infrastructure can be built on top of many different underlay network technologies. The high flexibility and centrally controlled feature of Software Defined Networking (SDN), make SDN networks to be a perfect underlay to build the SFC architecture. Due to Ternary Content Address Memory (TCAM) limited size, SDN switches have a limitation in the number of flow rules that can be hosted. This constraint is particularly penalizing in case of the SFC classifier function, since it requires to manage a high number of different flows. The limitation imposed by the TCAM size on the SFC classifier can be a bottleneck for the number of SFC requests that the SDN-based SFC architecture can handle. In this paper we define the Dynamic Chain Request Classification Offloading (D-CRCO) problem, as the one of maximizing the number of accepted SFC requests, having the possibility of: i) implement the SFC classifier also in a node that is internal to the SDN-based SFC domain, and ii) install classification rules in a reactive fashion. Furthermore, we propose the Dynamic Nearest Node (DNN) heuristic to solve the D-CRCO problem. Performance evaluation shows that by using DNN heuristic it is possible to triple the number of accepted requests, with respect to existing solutions
Small Angle X-ray Scattering From Lipid-bound Myelin Basic Protein In Solution
The structure of myelin basic protein (MBP), purified from the myelin sheath in both lipid-free (LF-MBP) and lipid-bound (LB-MBP) forms, was investigated in solution by small angle x-ray scattering. The water-soluble LF-MBP, extracted at pH 7.0. Under all conditions, the scattering from the two protein forms was different, indicating different molecular shapes. For the LB-MBP, well-defined scattering curves were obtained, suggesting that the protein had a unique, compact (but not globular) structure. Furthermore, these data were compatible with earlier results from molecular modeling calculations on the MBP structure which have been refined by us. In contrast, the LF-MBP data were in accordance with the expected open-coil conformation. The results represent the first direct structural information from x-ray scattering measurements on MBP in its native lipidic environment in solution.861 I455460Altschul, S.F., Madden, T.L., SchÀffer, A.A.Z.J., Zhang, Z., Miller, W., Gapped, L.D.J., BLAST and PSI-BLAST: A new generation of protein database search programs (1997) Nucleic Acids Res., 25, pp. 3389-3402Alvord, E.C., Kies, M.W., Suckling, A.L., (1984) Experimental Allergic Encephalomyelitis: A Useful Model for Multiple Sclerosis, , Alan R. Liss Inc., New YorkBates, I.R., Harauz, G., Molecular dynamics exposes α-helices in myelin basic protein (2003) J. Mol. Mod., , published online 24 July 2003Beniac, D.R., Luckevich, M.D., Czamota, G.J., Tompkins, T.A., Ridsdale, R.A., Ottensmeyer, F.P., Moscarello, M.A., Harauz, G., Three-dimensional structure of myelin basic protein. I. Reconstruction via angular reconstitution of randomly oriented single particles (1997) J. Biol. Chem., 272, pp. 4261-4268Berman, H.M., Westbrook, J., Feng, Z., Gilliland, G., Bhat, T.N., Weissig, H., Shindyalov, I.N., Bourne, P.E., The Protein Data Bank (2000) Nucleic Acids Res., 28, pp. 235-242Bobba, A., Munno, I., Greco, B., Pellegrino, N.M., Riccio, P., Jirillo, E., Quagliariello, E., On the spontaneous adherence of myelin basic protein to T-lymphocytes (1991) Biochem. Biophys. Res. Commun., 180, pp. 1125-1129Boggs, J.M., Moscarello, M.A., Papahadiopolos, D., Structural organization of myelin-role of lipid-protein interactions determined in model systems (1982) Lipid-Protein Interactions, 2, pp. 1-51. , P. C. Jost and O. H. Griffith, editors. Wiley & Sons, New YorkDeibler, G., Martenson, R.E., Kies, M.W., Large-scale preparation of myelin basic protein from central nervous tissue of several mammalian species (1972) Prep. Biochem., 2, pp. 139-165Deibler, G.E., Boyd, L.F., Kies, M.W., Proteolytic activity associated with purified myelin basic protein (1984) Experimental Allergic Encephalomyelitis: A Useful Model for Multiple Sclerosis, pp. 249-256. , E. C. Alvord Jr., M. W. Kies, and A. J. Suckling, editors. Liss, New YorkEpand, R.M., Moscarello, M.A., Zierenberg, B., Vail, W.J., The folded conformation of the encephalogenic protein of the human brain (1974) Biochemistry, 13, pp. 1264-1267Garavito, R.M., Ferguson-Miller, S., Detergents as tools in membrane biochemistry (2001) J. Biol. Chem., 276, pp. 32403-32406Glatter, O., Convolution square root of band-limited symmetrical functions and its applications to small-angle scattering data (1981) J. Appl. Crystallogr., 14, pp. 101-108Gow, A., Smith, R., The thermodynamically stable state of myelin basic protein in solution is a flexible coil (1989) Biochem. J., 257, pp. 535-540Guinier, A., Fournet, G., (1955) Small-Angle Scattering of X-Rays, , Wiley & Sons, New YorkHaas, H., Torrielli, M., Steitz, R., Cavatorta, P., Sorbi, R., Riccio, P., Gliozzi, A., Myelin model membranes on solid substrate (1998) Thin Sol. Films, 327-329, pp. 627-631Kellermann, G., Vicentin, E., Tamura, E., Rocha, M., Tolentino, H., Barbosa, A., Craievich, A., Torriani, I., The small-angle x-ray scattering beamline of the Brazilian Synchrotron Light Laboratory (1997) J. Appl. Crystallogr., 30, pp. 880-883Kirschner, D.A., Blaurock, A.E., Organization, phylogenetic variations and dynamic transitions of myelin (1992) Myelin: Biology and Chemistry, pp. 3-78. , R. E. Martenson, editor. CRC Press, Boca Raton, FLKrigbaum, W.R., Hsu, T.S., Molecular conformation of bovine A1 basic protein, a coiling macromolecule in aqueous solution (1975) Biochemistry, 14, pp. 2542-2546Liebes, L.F., Zand, R., Phillips, W.D., Solution behavior, circular dichroism and 22 MHz PMR studies of the bovine myelin basic protein (1975) Biochim. Biophys. Acta, 405, pp. 27-39Liuzzi, G.M., Tamborra, R., Ventola, A., Bisaccia, F., Quagliariello, E., Riccio, P., Different recognition by clostripain of myelin basic protein in the lipid-bound and lipid-free forms (1996) Biochem. Biophys. Res. Commun., 226, pp. 566-571Lolli, F., Liuzzi, G.M., Vergelli, M., Massacesi, L., Ballerini, C., Amaducci, L., Riccio, P., Antibodies specific for the lipid-bound form of myelin basic protein during experimental autoimmune encephalomyelitis (1993) J. Neuroimmunol., 44, pp. 69-76Massacesi, L., Vergelli, M., Zehetbauer, B., Liuzzi, G.M., Olivotto, J., Ballerini, C., Uccelli, A., Amaducci, L., Induction of the autoimmune encephalomyelitis in rats and immune response to myelin basic protein in lipid bound form (1993) J. Neurol. Sci., 119, pp. 91-98Mazzanti, B., Vergelli, M., Riccio, P., Martin, R., McFarland, H.F., Liuzzi, M.G., Amaducci, L., Massacesi, L., T-cell response to myelin basic protein and lipid-bound myelin basic protein in patients with Multiple Sclerosis and health donors (1998) J. Neuroimmunol., 82, pp. 96-100Moscarello, M.A., Evolving biological concepts and therapeutic approaches (1996) Cell Biology and Pathology of Myelin, , R. M. Devon, R. Doucette, B. H. J. Juurlink, A. J. Nazarali, D. J. Schreyer, and V. M. K. Verge, editors. Plenum Publishing, New YorkOliveira, C.L.P., Dos Santos, D.R., Kellermann, G., Plivelic, T., Torriani, I.L., Data treatment program for the SAXS beamline (1997) LNLS Technical Note, , unpublished, available for beam line usersPerkins, J.P., X-ray and neutron solution scattering (1988) Modern Physical Methods in Biochemistry, Part B, pp. 134-265. , A. Neuberger and L. L. M. van Deenen, editors. Elsevier, Amsterdam, The NetherlandsPolverini, E., Fasano, A., Zito, F., Riccio, P., Cavatorta, P., Conformation of bovine myelin basic protein purified with bound lipids (1999) Eur. Biophys. J., 28, pp. 351-355Readhead, C., Popko, B., Takahashi, N., Shine, H.D., Saavedra, R.A., Sidman, R.L., Hood, L., Expression of a myelin basic protein gene in transgenic mice: Correlation of the dismyelinating phenotype (1987) Cell, 48, pp. 703-712Riccio, P., Rosenbusch, J.P., Quagliarello, E., A new procedure to isolate brain myelin basic protein in a lipid-bound form (1984) FEBS Lett., 177, pp. 236-240Riccio, P., Masotti, L., Cavatorta, P., De Santis, A., Juretic, D., Bobba, A., Pasquali-Ronchetti, I., Quagliariello, E., Myelin basic protein ability to organize lipid bilayers: Structural transitions in bilayers of lysophosphatidylcholine micelles (1986) Biochem. Biophys. Res. Commun., 134, pp. 313-319Riccio, P., Quagliariello, E., Lipid-bound, native-like, myelin basic protein: A well-known protein in a new guise, or an unlikely story? (1993) J. Neurochem., 61, pp. 787-788Riccio, P., Bobba, A., Romito, E., Minetola, M., Quagliariello, E., A new detergent to purify CNS myelin basic protein isoforms in lipid-bound form (1994) Neuroreport, 24, pp. 689-692Riccio, P., Fasano, A., Borenshtein, N., Bleve-Zacheo, T., Kirschner, D.A., Multilamellar packing of myelin modeled by lipid-bound MBP (2000) J. Neurosci. Res., 59, pp. 513-521Ridsdale, R.A., Beniac, D.R., Tompkins, T.A., Moscarello, M.A., Harauz, G., Three-dimensional structure of myelin basic protein. II. Molecular modeling and considerations of predicted structures in multiple sclerosis (1997) J. Biol. Chem., 272, pp. 4269-4275Rosenbusch, J.P., Stability of membrane proteins: Relevance for the selection of appropriate methods for high-resolution structure determinations (2001) J. Struct. Biol., 136, pp. 144-157Semenyuk, V., Svergun, D.I., GNOM - A program package for small angle scattering data processing (1991) J. Appl. Crystallogr., 24, pp. 537-540Smith, R., Self-association of myelin basic protein: Enhancement by detergents and lipids (1982) Biochemistry, 12, pp. 2697-2701Smith, R., The basic protein of CNS myelin: Its structure and ligand binding (1992) J. Neurochem., 59, pp. 1589-1608Staugaitis, S.M., Colman, D.R., Pedraza, L., Membrane adhesion and other functions for the myelin basic proteins (1996) Bioessays, 18, pp. 13-18Stoffel, W., The myelin membrane of the central nervous system-essential macromolecular structure and function (1990) Angew. Chem. Int. Ed. Engl., 29, pp. 958-976Svergun, D.I., Petoukhov, M.V., Koch, M.H.J., Determination of domain structure of proteins from x-ray solution scattering (2001) Biophys. J., 80, pp. 2946-2953Vergelli, M., Pinet, V., Vogt, A.B., Kalbus, M., Malnati, M., Riccio, P., Long, E.O., Martin, R., HLA-DR-restricted presentation of purified myelin basic protein is independent of intracellular processing (1997) Eur. J. Immunol., 27, pp. 941-951Vriend, G., WHAT IF: A molecular modeling and drug design program (1990) J. Mol. Graph., 8, pp. 52-5
Effect of lipopolysaccharides on vascular endothelial growth factor expression in mouse pulp cells and macrophages
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71399/1/j.1600-0722.2003.00041.x.pd
The complex TIE between macrophages and angiogenesis
Macrophages are primarily known as phagocytic immune cells, but they also play a role in diverse processes, such as morphogenesis, homeostasis and regeneration. In this review, we discuss the influence of macrophages on angiogenesis, the process of new blood vessel formation from the pre-existing vasculature. Macrophages play crucial roles at each step of the angiogenic cascade, starting from new blood vessel sprouting to the remodelling of the vascular plexus and vessel maturation. Macrophages form promising targets for both pro- and anti-angiogenic treatments. However, to target macrophages, we will first need to understand the mechanisms that control the functional plasticity of macrophages during each of the steps of the angiogenic cascade. Here, we review recent insights in this topic. Special attention will be given to the TIE2-expressing macrophage (TEM), which is a subtype of highly angiogenic macrophages that is able to influence angiogenesis via the angiopoietin-TIE pathway
Angiogenesis induced by tumor necrosis factor-agr; is mediated by α4 integrins
Tumor necrosis factor-α (TNF-α) and fibroblast growth factor-2 (FGF-2 or bFGF) are potent stimulators of angiogenesis. TNF-α, but not FGF-2, can induce the expression of vascular cell adhesion molecule-1 (VCAM-1) on the surface of endothelial cells. The soluble form of VCAM-1 has recently been demonstrated to function as an angiogenic mediator. Here we demonstrate that monoclonal antibodies directed against VCAM-1 or its α4 integrin counter-receptor inhibited TNF-α-induced endothelial cell migration in vitro. Angiogenesis induced in vivo in rat corneas by TNF-α was inhibited by a neutralizing antibody directed against the rat α4 integrin subunit. A peptide antagonist of the a4 integrins blocked TNF-α-induced endothelial cell migration in vitro and angiogenesis in rat corneas in vivo. No inhibition by the antibodies or peptide antagonist was observed either in vitro or in vivo when FGF-2 was used as the stimulus. The peptide antagonist did not inhibit TNF-a binding to its receptor nor did it block the function of αvÎČ3, an integrin previously implicated in TNF-a and FGF-2 mediated angiogenesis. These results demonstrate that angiogenic processes induced by TNF-α are mediated in part by agr;4 integrins possibly by a mechanism involving the induction of soluble VCAM-1.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41761/1/10456_2004_Article_188219.pd
Informal and formal reconciliation strategies of older peoplesâ working carers: the European carers@work project
Faced with a historically unprecedented process of demographic ageing, many European societies implemented pension reforms in recent years to extend working lives. Although aimed at rebalancing public pension systems, this approach has the unintended side effect that it also extends the number of years in which working carers have to juggle the conflicting demands of employment and caregiving. This not only impinges on working carersâ well-being and ability to continue providing care but also affects European enterprisesâ capacity to generate growth which increasingly relies on ageing workforces. The focus of this paper will thus be a cross-national comparison of individual reconciliation strategies and workplace-related company policies aimed at enabling working carers to reconcile both conflicting roles in four different European welfare states: Germany, Italy, Poland, and the United Kingdom
- âŠ