Lay leadership dinner

Immanuel Janssen, master of ceremonies; R. Hopmann, L. Hempelmann, J. Klotz, R. Meyer, M. Miller, S. Nafzger, R. Bohlmann, speakers. Recorded May 7, 1981

The Northern Engineer, Vol. 06, no. 4 (Winter 1974)

What's Old in Geothermal Energy / Lee Leonard -- Permafrost and Ground Stability / J. A. Heginbottom -- Waste Management in the North / Eb Rice ; Amos J. "Joe" Alter -- What You've Always Wanted to Know about Earthquakes ; Larry D. Gedney -- Estimating the Cost of Garbage Collection for Settlements in Northern Regions / Donald J. Gamble ; Christian T. L. Janssen -- International Symposium on Dredging Technology -- Design of Floors for Arctic Shelters / Axel R. Carlson -- Correction -- The Coast and Shelf of the Beaufort Sea -- Satellite Communication Systems Technolog

Statistics of the two-point transmission at Anderson localization transitions

At Anderson critical points, the statistics of the two-point transmission $T_L$ for disordered samples of linear size $L$ is expected to be multifractal with the following properties [Janssen {\it et al} PRB 59, 15836 (1999)] : (i) the probability to have $T_L \sim 1/L^{\kappa}$ behaves as $L^{\Phi(\kappa)}$, where the multifractal spectrum $\Phi(\kappa)$ terminates at $\kappa=0$ as a consequence of the physical bound $T_L \leq 1$; (ii) the exponents $X(q)$ that govern the moments $\overline{T_L^q} \sim 1/L^{X(q)}$ become frozen above some threshold: $X(q \geq q_{sat}) = - \Phi(\kappa=0)$, i.e. all moments of order $q \geq q_{sat}$ are governed by the measure of the rare samples having a finite transmission ($\kappa=0$). In the present paper, we test numerically these predictions for the ensemble of $L \times L$ power-law random banded matrices, where the random hopping $H_{i,j}$ decays as a power-law $(b/| i-j |)^a$. This model is known to present an Anderson transition at $a=1$ between localized ($a>1$) and extended ($a<1$) states, with critical properties that depend continuously on the parameter $b$. Our numerical results for the multifractal spectra $\Phi_b(\kappa)$ for various $b$ are in agreement with the relation $\Phi(\kappa \geq 0) = 2 [ f(\alpha= d+ \frac{\kappa}{2}) -d ]$ in terms of the singularity spectrum $f(\alpha)$ of individual critical eigenfunctions, in particular the typical exponents are related via the relation $\kappa_{typ}(b)= 2 (\alpha_{typ}(b)-d)$. We also discuss the statistics of the two-point transmission in the delocalized phase and in the localized phase.Comment: v2=final version with two new appendices with respect to v1; 12 pages, 10 figure

Coupled quantum wires

We study a set of crossed 1D systems, which are coupled with each other via tunnelling at the crossings. We begin with the simplest case with no electron-electron interactions and find that besides the expected level splitting, bound states can emerge. Next, we include an external potential and electron-electron interactions, which are treated within the Hartree approximation. Then, we write down a formal general solution to the problem, giving additional details for the case of a symmetric external potential. Concentrating on the case of a single crossing, we were able to explain recent experinents on crossed metallic and semiconducting nanotubes [J. W. Janssen, S. G. Lemay, L. P. Kouwenhoven, and C. Dekker, Phys. Rev. B 65, 115423 (2002)], which showed the presence of localized states in the region of crossing.Comment: 11 pages, 10 figure

The determination of the magnetoelectric coupling coefficient in ferroelectric-ferromagnetic composite base on PZT-ferrite

In the present work, the magnetoelectric coupling coefficient, from the temperature dependences of the dielectric permittivity for the multiferroic composite was determined. The research material was ferroelectric–ferromagnetic composite on the based PZT and ferrite. We investigated the temperature dependences of the dielectric permittivity (") for the different frequency of measurement’s field. From the dielectric measurements we determined the temperature of phase transition from ferroelectric to paraelectric phase. For the theoretical description of the temperature dependence of the dielectric constant, the Hamiltonian of Alcantara, Gehring and Janssen was used. To investigate the dielectric properties of the multiferroic composite this Hamiltonian was expressed under the mean–field approximation. Based on dielectric measurements and theoretical considerations, the values of the magnetoelectric coupling coefficient were specified.[1] Z. S u r o w i a k, D. B o c h e n e k, Archives of Acoustics 33,2, 243-260 (2008). [2] J.A. B a r t k o w s k a, J. I l c z u k, Int. J Thermophys. 31, 1 (2010). [3] J.A. B a r t k o w s k a, J. B l u s z c z, R. Z a c h a r i a s z, J. I l c z u k, B. B r u s, J. Phys. IV France 137, 19 (2006). [4] J.A. B a r t k o w s k a, J. C i s o w s k i, J. V o i r o n, J. H e i m a n n, M. C z a j a, Z. M a z u r a k, J Magn. Magn.Mat. 221, 273 (2000). [5] Y. T o k u r a, Science 312, 1481 (2006). [6] T. K i m u r a, T. G o t o, H. S h i n t a n i, K. I s h i z a k a, T. A r i m a, Y. T o k u r a, Nature (London) 426, 55 (2003). [7] D. B o c h e n e k, P. N i e m i e c, R. Z a c h a r i a s z, A. C h r o b a k, G. Z i ó ł k o w s k i, Archives of Metallurgy and Materials 58, 1013 (2013). [8] O.F. A l c a n t a r a, G.A. G e h r i n g, Adv. Phys. 29, 731 (1980). [9] T. J a n s s e n, J.A. T j i o n, Phys. Rev. B 24, 2245 (1981). [10] M.H. W h a n g b o, H.-J. K o o, D. D a i, J. Solid State Chem. 176, 417 (2003). [11] T. J a n s s e n, J.A. T j i o n, Phys. Rev. B 24, 2245 (1981). [12] X.S. G a o, J.M. L i u, X.Y. C h e n, Z.G. L i u, J. Appl. Phys. 88, 4250 (2000). [13] X.S. G a o, J.M. L i u, Q.C. L i, Z.G. L i u, Ferroelectrics 252, 69 (2001). [14] Z. X u, Y. F e n g, S. Z h e n g, A. J i n, F. W a n g, X. Y a o, J. Appl. Phys. 92, 5, 2663 (2002). [15] M. K u m a r, K.L. Y a d a v, J. Phys.: Condens. Matter 19, 242202 (2007)

Bibliographie de l'histoire de Belgique : bibliografie van de geschiedenis van België. 1990

Van Eenoo Romain, Bovesse J., Vrielinck S., Janssen R., Vanthemsche Guy, Geirnaert Ν., Meyers W., François L., Maréchal Griet, Vanhaute E., Art J., Haesenne-Peremans N., Cauchies Jean-Marie, Lis Catharina, Gaus H., Vermeulen U., Triaille-Closset C., Prevenier Walter, Van Derveeghde Denise, Petit R., Hélin Etienne. Bibliographie de l'histoire de Belgique — Bibliografie van de geschiedenis van België. 1990. In: Revue belge de philologie et d'histoire, tome 70, fasc. 2, 1992. Histoire médiévale, moderne et contemporaine — Middeleeuwse, moderne en hedendaagse geschiedenis. pp. 420-546

The activation dependent adhesion of macrophages to laminin involves cytoskeletal anchoring and phosphorylation of the alpha 6 beta 1 integrin

Macrophages require activation with either PMA (Mercurio, A. M., and L. M. Shaw. 1988. J. Cell Biol. 107:1873-1880) or interferon-gamma (Shaw, L. M., and A. M. Mercurio. 1989. J. Exp. Med. 169:303-308) to adhere to a laminin substratum. In the present study, we identified an integrin laminin receptor on macrophages and characterized cellular changes that occur in response to PMA activation that facilitate laminin adhesion. A monoclonal antibody (GoH3) that recognizes the integrin alpha 6 subunit (Sonnenberg, A., H. Janssen, F. Hogervorst, J. Calafat, and J. Hilgers. 1987. J. Biol. Chem. 262:10376-10383) specifically inhibited adhesion to laminin-coated surfaces. This antibody precipitated an alpha 6 beta 1 heterodimer (Mr 130/110 kD) from 125I surface-labeled macrophages. The amount of radiolabeled receptor on the cell surface did not increase after PMA activation. Thus, the induction of laminin adhesion cannot be attributed to de novo or increased surface expression of alpha 6 beta 1. By initially removing the Triton X-100-soluble fraction of macrophages and then disrupting the remaining cytoskeletal framework, we observed that 75% of the alpha 6 beta 1 heterodimer on the cell surface is anchored to the cytoskeleton in macrophages that had adhered to a laminin substratum in response to PMA. Significant cytoskeletal anchoring of this receptor was not observed in macrophages that had adhered to fibronectin or tissue culture plastic, nor was it seen in nonadherent cells. PMA also induced phosphorylation of the cytoplasmic domain of the alpha 6 subunit, but not the beta 1 subunit. Phosphorylated alpha 6 was localized to the cytoskeletal fraction only in macrophages plated on a laminin substratum. In summary, our results support a mechanism for the regulation of macrophage adhesion to laminin that involves specific and dynamic matrix integrin-cytoskeletal interactions that may be facilitated by integrin phosphorylation