The reform process of the railway sector in Europe: A disaggregated regulatory approach

The railroad package of 2001 focusing on access regulation is in the process of a reform. Particularly, the European Commission intends to remove the obstacles to fair competition that have been identified since 2001. In this context, the paper points out the relevance of the disaggregated regulatory approach. It is necessary to differentiate between infrastructure components which are monopolistic bottlenecks (e.g. railway tracks) and competitive components (e. g. service functions like ticketing). Competition on the markets for railway transport services requires non-discriminatory access to the railway infrastructures. As well the horizontal interoperability between national railway networks is a prerequisite that full competition on European markets for railway services can evolve. Train access charges should provide incentives for the different track companies to participate in collaborations offering international cross-border based track capacities, whereas a regulatory prescription of international track corridors conflicts with the competence to allocate the track capacities of the different track companies. Finally, the complex question of the interplay between discrimination and the deficit problem is addressed in order to present solutions to avoid crosssubsidization between track infrastructure and markets for transport services and to guarantee the efficient usage of public funds. --

Stepping stones and access holidays: the fallacies of regulatory micro-management

Good intentions are no substitute for sound economic regulation. Using the ‘in-vestment ladder’ as the stick and access holidays as the carrot is hardly an ef-fective way to generate competition. On the contrary, this approach creates a regulatory spiral. What regulators plead for today is in effect an obligatory shar-ing regime for nearly all network elements. However, this splitting up of net-works into their elements by ad hoc regulatory interventions is destroying con-sumer welfare. Instead, rule-based regulation of network-specific market power should be implemented by means of a disaggregated regulatory mandate, limit-ing incentive regulation to essential facilities as a whole. --

Non-classic properties of human cytolytic lymphocytes. basic and clinical aspects

The immune system comprises a complex network of specialized cells and organs that function together to recognize and remove potentially harmful "non-self", i.e. pathogens, malignant cells and –by extension– also transplanted allogeneic cells. Innate –evolutionary ‘old’ – immune mechanisms function in a non-clonal germlineencoded manner, whereas the hallmark of the adaptive immune system is clonal expansion of cells after rearrangement of germline-encoded immune receptors. Natural killer cells (NK cells) represent an important component of the innate immune system, whereas CD4+ (‘helper’) and CD8+ (‘cytotoxic’) T cells are key players of adaptive immunity. Rare NK cell-deficient humans suffer from overwhelming herpes viral infections, indicative of their important role in infection biology. Mechanistic insight into their antiviral effector function, however, remains largely based on murine data. Intriguingly, the best molecular understanding of NK cell function in humans is derived from studies of the ‘man-made’ setting of allo-stem cell transplantation. By contrast, in solid organ transplantation NK cells have, until the recent emergence of exciting murine data, been largely ignored. To begin to understand the role NK cells may play in human solid organ transplantation, we initiated a prospective cohort-study of kidney allo-transplant recipients. Blocking the IL-2 receptor α-chain (CD25) with mAb is an immunomodulatory treatment modality used in various clinical situations, including allo-transplantation. Of note, in patients with multiple sclerosis and uveitis administration of anti-CD25 mAb has been linked to robust expansion of CD56bright NK cells, which has been suggested to mediate its effect. On this background we first we enumerated NK cell-subsets in kidney transplant-recipients receiving anti-CD25 mAb (n=16) before transplantation, and at week 12, 26 and 52 post-transplantation, and in healthy controls (n=5). In healthy controls NK cell-subsets remained stable over time. In transplant-recipients, by contrast, overall median frequencies of both CD56bright and CD56dim NK cells transiently decreased after transplantation. Expansion of CD56bright NK cells was observed in only 6/16 patients. These data dissociate expansion of CD56bright NK cells and in vivo blockade of CD25 in kidney allograft recipients, thus dismissing expansion of CD56bright NK cells as unifying clinical hallmark of its effect across all clinical situations (G. Zenhaeusern et al. Submitted). Aiming next at studying functional allo-specific properties of NK cells, we developed a simple, paraformaldehyde fixation-based protocol that provided an accurate and robust means for assessing alloreactivity, avoiding an irradiation-induced network of various cytokines complicating interpretation of results (G. Zenhaeusern et al. JIM ‘07). Using this protocol, we found that a subset of NK cells was activated rather than silenced when interacting with cells expressing normal levels of autologous MHC I. Instead of inducing an inflammatory phenotype, however, activation led to the secretion of the regulatory cytokines TGF-β and IL-10. Together these data ascribe a novel pattern of reactivity to NK cells with potential implications both in autologous and allogeneic systems (G. Zenhaeusern et al. in revision). The molecular understanding of the various cellular interactions involving NK cells is only emerging, whereas recognition by T cell receptor (TCR) of cognate antigen presented by HLA molecules has been analyzed in depth. On the other hand, relatively little attention has been given to basic T cell physiological properties, such as their random crawling activity (required to screen for antigen) or their mitochondrial energy efficiency. In order to begin to tackle these important issues, I established an experimental in vitro system allowing us to quantify random crawling activity of various T cell subsets, and monitor crawling under conditions mimicking the intra- and extravascular environment. Using these assays, we identified robust differences between phenotypically distinct subsets of CD8+ T cells with regards to their random movement activity and the frequency-distribution of crawling cells. Specifically, using migration-assays and time-lapse microscopy we found (i) that CD8+ T cells lacking the lymph node homing receptors CCR7 and CD62L migrated more efficiently in trans-well assays and (ii) that these same cells were characterized by a high frequency of cells exhibiting random crawling activity under culture conditions mimicking the interstitial/extravascular milieu –but not when examined on endothelial cells. With this finding at hand, we hypothesized that increased random movement activity ought to be linked to higher energy consumption. To test this hypothesis we measured mRNA expression of genes key to mitochondrial energy metabolism (PGC-1β, ERRα, Cytochrome C, ATP Synthase, and the uncoupling proteins UCP-2 and UCP-3), quantified cellular ATP contents and performed micro-calorimetric analyses. Much to our surprise, ATP contents were consistently higher in CCR7+ CD8+ T cells, the subset of T cells that showed less crawling activity, and genes involved in mitochondrial biosynthesis and ATP production (PGC-1β, ERRα, Cytochrome C, ATP Synthase) were significantly upregulated. Intriguingly, we also observed that these CCR7+ CD8+ T cells expressed uncoupling proteins UCP-2 and UCP-3 at significantly higher levels than CCR7- CD8+ T cells, which at least partly explained the higher heat flow measured in the lymph node homing T cell subset. (G. Zenhaeusern et al. Blood 2008, e-pub ahead print). Together these assays identified a phenotypically distinct ‘high crawlingfrequency’ CD8+ T cell population, and differentially regulated heat production among non-lymphoid vs. lymphoid homing CD8+ T cells

Regulation of new markets in telecommunications? Market dynamics and shrinking monopolistic bottlenecks

This paper aims at localizing network-specific market power in new markets. Three kinds of transmission qualities on service markets can be differentiated according to the products provided: narrowband services like PSTN/ISDN or GSM, semi high-speed broadband services like broadband internet access up to 6 Mbps download and VDSL services up to 50 Mbps. As long as, due to the absence of alternative network infrastructures, a monopolistic bottleneck in local infrastructure networks exists the question arises what the remaining bottleneck components are for these different markets. In this paper the shrinking-bottleneck hypothesis will be demonstrated. --

Scale-Invariant Models of Gravity and Particle Physics and their Cosmological Implications

Currently, the best theoretical description of fundamental matter and its gravitational interaction is given by the Standard Model (SM) of particle physics and Einstein's theory of General Relativity (GR). These theories contain a number of seemingly unrelated scales. While Newton's gravitational constant and the mass of the Higgs boson are parameters in the classical action, the masses of other elementary particles are due to the electroweak symmetry breaking. Yet other scales, like ΛQCD associated to the strong interaction, only appear after the quantization of the theory. We reevaluate the idea that the fundamental theory of nature may contain no fixed scales and that all observed scales could have a common origin in the spontaneous break-down of exact scale invariance. To this end, we consider a few minimal scale-invariant extensions of GR and the SM, focusing especially on their cosmological phenomenology. In the simplest considered model, scale invariance is achieved through the introduction of a dilaton field. We find that for a large class of potentials, scale invariance is spontaneously broken, leading to induced scales at the classical level. The dilaton is exactly massless and practically decouples from all SM fields. The dynamical break-down of scale invariance automatically provides a mechanism for inflation. Despite exact scale invariance, the theory generally contains a cosmological constant, or, put in other words, flat spacetime need not be a solution. We next replace standard gravity by Unimodular Gravity (UG). This results in the appearance of an arbitrary integration constant in the equations of motion, inducing a run-away potential for the dilaton. As a consequence, the dilaton can play the role of a dynamical dark-energy component. The cosmological phenomenology of the model combining scale invariance and unimodular gravity is studied in detail. We find that the equation of state of the dilaton condensate has to be very close to the one of a cosmological constant. If the spacetime symmetry group of the gravitational action is reduced from the group of all diffeomorphisms (Diff) to the subgroup of transverse diffeomorphisms (TDiff), the metric in general contains a propagating scalar degree of freedom. We show that the replacement of Diff by TDiff makes it possible to construct a scale-invariant theory of gravity and particle physics in which the dilaton appears as a part of the metric. We find the conditions under which such a theory is a viable description of particle physics and in particular reproduces the SM phenomenology. The minimal theory with scale invariance and UG is found to be a particular case of a theory with scale and TDiff invariance. Moreover, cosmological solutions in models based on scale and TDiff invariance turn out to generically be similar to the solutions of the model with UG. In usual quantum field theories, scale invariance is anomalous. This might suggest that results based on classical scale invariance are necessarily spoiled by quantum corrections. We show that this conclusion is not true. Namely, we propose a new renormalization scheme which allows to construct a class of quantum field theories that are scale-invariant to all orders of perturbation theory and where the scale symmetry is spontaneously broken. In this type of theory, all scales, including those related to dimensional transmutation, like ΛQCD, appear as a consequence of the spontaneous break-down of the scale symmetry. The proposed theories are not renormalizable. Nonetheless, they are valid effective theories below a field-dependent cut-off scale. If the scale-invariant renormalization scheme is applied to the presented minimal scale-invariant extensions of GR and the SM, the goal of having a common origin of all scales, spontaneous breaking of scale invariance, is achieved

Regulation of New Markets in Telecommunications: Market Dynamics and Shrinking Monopolistic Bottlenecks

This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.This paper focuses on localising network-specific market power in new markets. Three levels of transmission quality in service markets can be differentiated according to the products provided: narrowband services like PSTN/ISDN or GSM, semi high-speed broadband services, like broadband internet access up to 6 Mbps download, and VDSL services up to 50 Mbps. As long as a monopolistic bottleneck exists in local infrastructure networks due to the absence of alternative network infrastructures, the question arises what the remaining bottleneck components are for these different markets. In this paper, the shrinking bottleneck hypothesis will be demonstrated.Peer Reviewe

Higgs-dilaton cosmology: From the early to the late Universe

We consider a minimal scale-invariant extension of the standard model of particle physics combined with unimodular gravity formulated in [M. Shaposhnikov and D. Zenhausern, Phys. Lett. B 671, 187 (2009).]. This theory is able to describe not only an inflationary stage, related to the standard model Higgs field, but also a late period of dark-energy domination, associated with an almost massless dilaton. A number of parameters can be fixed by inflationary physics, allowing us to make specific predictions for any subsequent period. In particular, we derive a relation between the tilt of the primordial spectrum of scalar fluctuations, ns, and the present value of the equation of state parameter of dark energy (DE), wDE0. We find bounds for the scalar tilt, ns-1. The relation between ns and wDE0 allows us to use the current observational bounds on ns to further constrain the dark-energy equation of state to 0<1+wDE0<0.02, which is to be confronted with future dark-energy surveysWe acknowledge financial support from the Madrid Regional Government (CAM) under the Program No. HEPHACOS P-ESP-00346 and MICINN under Grant No. AYA2009-13936-C06-06. We also participate in the Consolider-Ingenio 2010 PAU (CSD2007-00060), as well as in the European Union Marie Curie Network UniverseNet under Contract No. MRTN-CT-2006-035863. J. R. would like to acknowledge financial support from UAM/CSIC. The work of M. S. and D. Z. was supported by the Swiss National Science Foundation and by the Tomalla Foundatio

Fellángolás és állhatatosság: A kommunikáció fontossága vezetőknél, különös tekintettel a médiákban való szereplésre a vezetői kommunikációról öt tézis és tizenkét téveszme alapján

Egyetlen elhibázott nyilvános szereplés szét tudja rombolni az arculatot és egyúttal a karriert. Nemrégiben kiderült, hogy sok vezető nem elég érett a médiák és a nyilvánosság nyomásának elviselésére. Ezért a kommunikációs készség napjainkban fontosabb, mint valaha. Aki helyesen tud kommunikálni, az értéket tud teremteni