The relationship between insulin binding, insulin activation of insulin-receptor tyrosine kinase, and insulin stimulation of glucose uptake in isolated rat adipocytes

We have studied the relationship between insulin activation of insulin-receptor kinase and insulin stimulation of glucose uptake in isolated rat adipocytes. Glucose uptake was half-maximally or maximally stimulated, respectively, when only 4% or 14% of the maximal kinase activity had been reached. To investigate this relationship also under conditions where the insulin effect on activation of receptor kinase was decreased, the adipocytes were exposed to 10 microM-isoprenaline alone or with 5 micrograms of adenosine deaminase/ml. An approx. 30% (isoprenaline) or approx. 50% (isoprenaline + adenosine deaminase) decrease in the insulin effect on receptor kinase activity was found at insulin concentrations between 0.4 and 20 ng/ml, and this could not be explained by decreased insulin binding. The decreased insulin-effect on kinase activity was closely correlated with a loss of insulin-sensitivity of glucose uptake. Moreover, our data indicate that the relation between receptor kinase activity and glucose uptake (expressed as percentage of maximal uptake) remained unchanged. The following conclusions were drawn. (1) If activation of receptor kinase stimulates glucose uptake, only 14% of the maximal kinase activity is sufficient for maximal stimulation. (2) Isoprenaline decreases the coupling efficiency between insulin binding and receptor-kinase activation, this being accompanied by a corresponding decrease in sensitivity of glucose uptake. (3) Our data indicate that the signalling for glucose uptake is closely related to receptor-kinase activity, even when the coupling efficiency between insulin binding and kinase activation is altered. They thus support the hypothesis that receptor-kinase activity reflects the signal which originates from the receptor and which is transduced to the glucose-transport system

On the bend number of circular-arc graphs as edge intersection graphs of paths on a grid

Golumbic, Lipshteyn and Stern \cite{Golumbic-epg} proved that every graph can be represented as the edge intersection graph of paths on a grid (EPG graph), i.e., one can associate with each vertex of the graph a nontrivial path on a rectangular grid such that two vertices are adjacent if and only if the corresponding paths share at least one edge of the grid. For a nonnegative integer $k$, $B_k$-EPG graphs are defined as EPG graphs admitting a model in which each path has at most $k$ bends. Circular-arc graphs are intersection graphs of open arcs of a circle. It is easy to see that every circular-arc graph is a $B_4$-EPG graph, by embedding the circle into a rectangle of the grid. In this paper, we prove that every circular-arc graph is $B_3$-EPG, and that there exist circular-arc graphs which are not $B_2$-EPG. If we restrict ourselves to rectangular representations (i.e., the union of the paths used in the model is contained in a rectangle of the grid), we obtain EPR (edge intersection of path in a rectangle) representations. We may define $B_k$-EPR graphs, $k\geq 0$, the same way as $B_k$-EPG graphs. Circular-arc graphs are clearly $B_4$-EPR graphs and we will show that there exist circular-arc graphs that are not $B_3$-EPR graphs. We also show that normal circular-arc graphs are $B_2$-EPR graphs and that there exist normal circular-arc graphs that are not $B_1$-EPR graphs. Finally, we characterize $B_1$-EPR graphs by a family of minimal forbidden induced subgraphs, and show that they form a subclass of normal Helly circular-arc graphs

Quantum scissors: teleportation of single-mode optical states by means of a nonlocal single photon

We employ the quantum state of a single photon entangled with the vacuum (|1,0>-|0,1>), generated by a photon incident upon a symmetric beam splitter, to teleport single-mode quantum states of light by means of the Bennett protocol. Teleportation of coherent states results in truncation of their Fock expansion to the first two terms. We analyze the teleported ensembles by means of homodyne tomography and obtain fidelities of up to 99 per cent for low source state amplitudes. This work is an experimental realization of the quantum scissors device proposed by Pegg, Phillips and Barnett (Phys. Rev. Lett. 81, 1604 (1998)

Studies in the Sphingolipids Series. XV. Partial Synthesis of Anhy~ro Cerebrin of Yeast

The partial synthesis of anhydro cerebrin (Ila) - a compound resulting by the acid catalyzed release of yeast cerebrin (I) - was effected. The synthetic Ila and its diacetyl derivative (Ile) were identical with the authentic samples

Studies in the Sphingolipids Series. XIII. On the Ceramides and Ceramide Esters of C20-Phytosphingosine and Cio-Phytosphingosine Anhydro Base of Yeast

The N and 0-acylations of C20-phytosphingosine anhydro base (Ia) , C20 -anhydro cere\u27brin (Ila) and C20 -cerebrin (IIIa) with longchain fatty acid chlorides have been examined. The reactions have been carried out in both quinoline and N,N-dimethyl formamide. The ceramides and ceramide esters thus obtained are represented by formulas I-III

On the minimum and maximum selective graph coloring problems in some graph classes

Given a graph together with a partition of its vertex set, the minimum selective coloring problem consists of selecting one vertex per partition set such that the chromatic number of the subgraph induced by the selected vertices is minimum. The contribution of this paper is twofold. First, we investigate the complexity status of the minimum selective coloring problem in some specific graph classes motivated by some models described in Demange et al. (2015). Second, we introduce a new problem that corresponds to the worst situation in the minimum selective coloring; the maximum selective coloring problem aims to select one vertex per partition set such that the chromatic number of the subgraph induced by the selected vertices is maximum. We motivat

Kontribusi Pembiayaan Bank Syariah untuk Sektor Pertanian di Indonesia

Based on Islamic Banking Law Article 1 paragraph 2 funding was the main activity for Islamic banking in its function as a financial intermediary and drived real sector. This study was aim to determine how much the influences of SBIS, amount of DPK, Non Performing Financing and the exchange rate of dollar against the Islamic banking financing as well as the contribution of Islamic bank financing for the agricultural sector in Indonesia by using VAR/VECM approach. VECM results indicated variables that affected agricultural financing in the short term was variable LNER and SBIS. While in the long term variable lnDPK and lnNPF statistically significant against to agricultural financing. The results of IRF showed that lnDPK, lnNPF and LNER responded positively influencing the contribution of financing on Islamic bank for the agricultural sector in Indonesia. As for The contribution of financing on Islamic bank for the agricultural sector in Indonesia, LNER gave the largest contribution to the Islamic bank financing for the agricultural sector in Indonesia, followed by the variable SBIS, lnDPK, and lnNPF. The higher value of rupiah would increase the financing by the islamic banking for Agricultural sector, as would as the lower of rate SBIS would increase the financing of islamic banking