Self-organized critical and synchronized states in a nonequilibrium percolation model

We introduce a nonequilibrium percolation model which shows a self-organized critical (SOC) state and several periodic states. In the SOC state, the correlation length diverges slower than the system size, and the corresponding exponent depends non universally on the parameter of the model. The periodic states contain an infinite cluster covering only part of the system.Comment: 10 pages, Revtex, two uuencoded figure

Rhetoric of landscape architecture and interior design discourses: preparation for cross-disciplinary practice

In the current reform context, the uniqueness of local disciplinary practices is being forgotten in the race towards cross-disciplinary practice. The rhetoric of the pedagogic discourses of landscape architectural students and interior design students is described as part of a doctoral study undertaken to document practices and orientations prior to cross-disciplinary collaboration. We draw on the theoretical framework of Bernstein and the rhetorical method of Burke to study the grammars of 'landscape' representation employed within these disciplinary examples. We offer a method of investigating how prepared final year students may be for working in a cross-disciplinary manner. The discursive interactions of their work, as illustrated by four examples of drawn images and written text, are described. Comparisons of these examples show both similarities and differences in the students' grammars of representation within their disciplines. Furthermore, however, the findings suggest a progressive weakening of the grammars of the pedagogic discourses that apply to the concepts and procedures of both disciplines. This poses some key issues for educators. It is argued that while weak grammars foster students' deeper understanding of concepts, they also weaken the pedagogic identity and autonomy of their discipline. Strong grammars resist domination and subordination, ensuring the ongoing relative autonomy of a discipline

Finite-size effects in the self-organized critical forest-fire model

We study finite-size effects in the self-organized critical forest-fire model by numerically evaluating the tree density and the fire size distribution. The results show that this model does not display the finite-size scaling seen in conventional critical systems. Rather, the system is composed of relatively homogeneous patches of different tree densities, leading to two qualitatively different types of fires: those that span an entire patch and those that don't. As the system size becomes smaller, the system contains less patches, and finally becomes homogeneous, with large density fluctuations in time.Comment: 10 pages, 11 figure

Review of \u3cem\u3eGuest Workers and Resistance to U.S. Corporate Despotism.\u3c/em\u3e Immanuel Ness. Reviewed by Barbara Franz.

Book review of Immanuel Ness, Guest Workers and Resistance to U.S. Corporate Despotism, University of Illinois Press (2011). $70.00 (hardcover),$25.00 (paperback)

Doppler sonography of the uterine and the cubital arteries in normal pregnancies, preeclampsia and intrauterine growth restriction: evidence for a systemic vessel involvement

Aims: The decrease in uterine resistance during normal pregnancy is known to be related to invading trophoblast cells which derive from placental tissue. Uterine and peripheral resistance is elevated in preeclampsia. The aim of the present study was to prospectively examine uterine and peripheral resistance in pregnancies complicated by preeclampsia (PE), fetal intrauterine growth restriction (IUGR) and pregnancy induced hypertension (PIH). Methods: Sixty-seven women with normal pregnancies, 17 with PE, 12 with IUGR underwent Doppler sonographic investigation of the uterine and the cubital arteries. The Pulsatility Index (PI) was calculated for each vessel. Statistical analysis was performed and a P-value < 0.05 was considered significant. Results: Patients with preeclampsia and IUGR showed a significant higher resistance at the placental (mean PI 1.267 and 1.063), nonplacental (mean PI 1.631 and 1.124) and cubital artery (mean PI 3,777 and 3.995) compared to the normal pregnancy group (mean PI 0.678; 0.859 and 2.95 respectively). Mean birth weight in the PE group was 1409 g, in the IUGR group 1649 g and 3419 g in the normal pregnancy group. Conclusions: Pregnancies with IUGR are associated with elevated peripheral resistance in the maternal arterial system as seen in pregnancies with preeclampsia. Our findings encourage to further investigate the maternal vascular system in high risk pregnancies

Control of Grapholitha lobarzewskii in the region Bodensee

Im Rahmen eines durch die LVWO Weinsberg durchgeführten Ringversuchs konnte an 8 Standorten mit starkem Vorjahresbefall die Bekämpfung mittels Pheromonverwirrung überprüft werden. Die Untersuchung war aus 2 Gründen interessant: 1. Zeigt die Verwirrungsmethode auch bei hohem Ausgangsbefall ausreichend Wirkung? 2. Ist die Verwirrungsmethode auch auf kleinen Teilflächen sinnvoll einsetzbar

The liquid-glass transition of silica

We studied the liquid-glass transition of $SiO_2$ by means of replica theory, utilizing an effective pair potential which was proved to reproduce a few experimental features of silica. We found a finite critical temperature $T_0$, where the system undergoes a phase transition related to replica symmetry breaking, in a region where experiments do not show any transition. The possible sources of this discrepancy are discussed.Comment: 14 pages, 6 postscript figures. Revised version accepted for pubblication on J.Chem.Phy

Matching with respect to general concept inclusions in the Description Logic EL

Matching concept descriptions against concept patterns was introduced as a new inference task in Description Logics (DLs) almost 20 years ago, motivated by applications in the Classic system. For the DL EL, it was shown in 2000 that the matching problem is NP-complete. It then took almost 10 years before this NP-completeness result could be extended from matching to unification in EL. The next big challenge was then to further extend these results from matching and unification without a TBox to matching and unification w.r.t. a general TBox, i.e., a finite set of general concept inclusions. For unification, we could show some partial results for general TBoxes that satisfy a certain restriction on cyclic dependencies between concepts, but the general case is still open. For matching, we solve the general case in this paper: we show that matching in EL w.r.t. general TBoxes is NP-complete by introducing a goal-oriented matching algorithm that uses non-deterministic rules to transform a given matching problem into a solved form by a polynomial number of rule applications. We also investigate some tractable variants of the matching problem