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Despite a lot of re-structuring and many innovations in recent years, the securities transaction industry in the European Union is still a highly inefficient and inconsistently configured system for cross-border transactions. This paper analyzes the functions performed, the institutions involved and the parameters concerned that shape market and ownership structure in the industry. Of particular interest are microeconomic incentives of the main players that can be in contradiction to social welfare. We develop a framework and analyze three consistent systems for the securities transaction industry in the EU that offer superior efficiency than the current, inefficient arrangement. Some policy advice is given to select the 'best' system for the Single European Financial Market.
In recent years stock exchanges have been increasingly diversifying their operations into related business areas such as derivatives trading, post-trading services and software sales. This trend can be observed most notably among profit-oriented trading venues. While the pursuit for diversification is likely to be driven by the attractiveness of these investment opportunities, it is yet an open question whether certain integration activities are also efficient, both from a social welfare and from the exchanges' perspective. Academic contributions so far analyzed different business models primarily from the social welfare perspective, whereas there is only little literature considering their impact on the exchange itself. By employing a panel data set of 28 stock exchanges for the years 1999-2003 we seek to shed light on this topic by comparing the factor productivity of exchanges with different business models. Our findings suggest three conclusions: (1) Integration activity comes at the cost of increased operational complexity which in some cases outweigh the potential synergies between related activities and therefore leads to technical inefficiencies and lower productivity growth. (2) We find no evidence that vertical integration is more efficient and productive than other business models. This finding could contribute to the ongoing discussion about the merits of vertical integration from a social welfare perspective. (3) The existence of a strong in-house IT-competence seems to be beneficial to overcome.
Academic contributions on the demutualization of stock exchanges so far have been predominantly devoted to social welfare issues, whereas there is scarce empirical literature referring to the impact of a governance change on the exchange itself. While there is consensus that the case for demutualization is predominantly driven by the need to improve the exchange's competitiveness in a changing business environment, it remains unclear how different governance regimes actually affect stock exchange performance. Some authors propose that a public listing is the best suited governance arrangement to improve an exchange's competitiveness. By employing a panel data set of 28 stock exchanges for the years 1999-2003 we seek to shed light on this topic by comparing the efficiency and productivity of exchanges with differing governance arrangements. For this purpose we calculate in a first step individual efficiency and productivity values via DEA. In a second step we regress the derived values against variables that - amongst others - map the institutional arrangement of the exchanges in order to determine efficiency and productivity differences between (1) mutuals (2) demutualized but customer-owned exchanges and (3) publicly listed and thus at least partly outsider-owned exchanges. We find evidence that demutualized exchanges exhibit higher technical efficiency than mutuals. However, they perform relatively poor as far as productivity growth is concerned. Furthermore, we find no evidence that publicly listed exchanges possess higher efficiency and productivity values than demutualized exchanges with a customer-dominated structure. We conclude that the merits of outside ownership lie possibly in other areas such as solving conflicts of interest between too heterogeneous members.
It is widely believed that the ideal board in corporations is composed almost entirely of independent (outside) directors. In contrast, this paper shows that some lack of board independence can be in the interest of shareholders. This follows because a lack of board independence serves as a substitute for commitment. Boards that are dependent on the incumbent CEO adopt a less aggressive CEO replacement rule than independent boards. While this behavior is inefficient ex post, it has positive ex ante incentive effects. The model suggests that independent boards (dependent boards) are most valuable to shareholders if the problem of providing appropriate incentives to the CEO is weak (severe).
Wider participation in stockholding is often presumed to reduce wealth inequality. We measure and decompose changes in US wealth inequality between 1989 and 2001, a period of considerable spread of equity culture. Inequality in equity wealth is found to be important for net wealth inequality, despite equity's limited share. Our findings show that reduced wealth inequality is not a necessary outcome of the spread of equity culture. We estimate contributions of stockholder characteristics to levels and inequality in equity holdings, and we distinguish changes in configuration of the stockholder pool from changes in the influence of given characteristics. Our estimates imply that both the 1989 and the 2001 stockholder pools would have produced higher equity holdings in 1998 than were actually observed for 1998 stockholders. This arises from differences both in optimal holdings and in financial attitudes and practices, suggesting a dilution effect of the boom followed by a cleansing effect of the downturn. Cumulative gains and losses in stockholding are shown to be significantly influenced by length of household investment horizon and portfolio breadth but, controlling for those, use of professional advice is either insignificant or counterproductive. JEL Classification: E21, G11
We argue that the shape of the system-size dependence of strangeness production in nucleus-nucleus collisions can be understood in a picture that is based on the formation of clusters of overlapping strings. A string percolation model combined with a statistical description of the hadronization yields a quantitative agreement with the data at sqrt s_NN = 17.3 GeV. The model is also applied to RHIC energies.
We investigate the sensitivity of several observables to the density dependence of the symmetry potential within the microscopic transport model UrQMD (ultrarelativistic quantum molecular dynamics model). The same systems are used to probe the symmetry potential at both low and high densities. The influence of the symmetry potentials on the yields of pi-, pi+, the pi-/pi+ ratio, the n/p ratio of free nucleons and the t/3He ratio are studied for neutron-rich heavy ion collisions (208Pb+208Pb, 132Sn+124Sn, 96Zr+96Zr) at E_b=0.4A GeV. We find that these multiple probes provides comprehensive information on the density dependence of the symmetry potential.
DCD – a novel plant specific domain in proteins involved in development and programmed cell death
(2005)
Background: Recognition of microbial pathogens by plants triggers the hypersensitive reaction, a common form of programmed cell death in plants. These dying cells generate signals that activate the plant immune system and alarm the neighboring cells as well as the whole plant to activate defense responses to limit the spread of the pathogen. The molecular mechanisms behind the hypersensitive reaction are largely unknown except for the recognition process of pathogens. We delineate the NRP-gene in soybean, which is specifically induced during this programmed cell death and contains a novel protein domain, which is commonly found in different plant proteins.
Results: The sequence analysis of the protein, encoded by the NRP-gene from soybean, led to the identification of a novel domain, which we named DCD, because it is found in plant proteins involved in d evelopment and c ell d eath. The domain is shared by several proteins in the Arabidopsis and the rice genomes, which otherwise show a different protein architecture. Biological studies indicate a role of these proteins in phytohormone response, embryo development and programmed cell by pathogens or ozone.
Conclusion: It is tempting to speculate, that the DCD domain mediates signaling in plant development and programmed cell death and could thus be used to identify interacting proteins to gain further molecular insights into these processes.
Background: Osteoarthritis (OA) has a high prevalence in primary care. Conservative, guideline orientated approaches aiming at improving pain treatment and increasing physical activity, have been proven to be effective in several contexts outside the primary care setting, as for instance the Arthritis Self management Programs (ASMPs). But it remains unclear if these comprehensive evidence based approaches can improve patients' quality of life if they are provided in a primary care setting. Methods/Design: PraxArt is a cluster randomised controlled trial with GPs as the unit of randomisation. The aim of the study is to evaluate the impact of a comprehensive evidence based medical education of GPs on individual care and patients' quality of life. 75 GPs were randomised either to intervention group I or II or to a control group. Each GP will include 15 patients suffering from osteoarthritis according to the criteria of ACR. In intervention group I GPs will receive medical education and patient education leaflets including a physical exercise program. In intervention group II the same is provided, but in addition a practice nurse will be trained to monitor via monthly telephone calls adherence to GPs prescriptions and advices and ask about increasing pain and possible side effects of medication. In the control group no intervention will be applied at all. Main outcome measurement for patients' QoL is the GERMAN-AIMS2-SF questionnaire. In addition data about patients' satisfaction (using a modified EUROPEP-tool), medication, health care utilization, comorbidity, physical activity and depression (using PHQ-9) will be retrieved. Measurements (pre data collection) will take place in months I-III, starting in June 2005. Post data collection will be performed after 6 months. Discussion: Despite the high prevalence and increasing incidence, comprehensive and evidence based treatment approaches for OA in a primary care setting are neither established nor evaluated in Germany. If the evaluation of the presented approach reveals a clear benefit it is planned to provide this GP-centred interventions on a much larger scale.
Cancer has become one of the most fatal diseases. The Heidelberg Heavy Ion Cancer Therapy (HICAT) has the potential to become an important and efficient treatment method because of its excellent “Bragg peak” characteristics and on-line irradiation control by the PET diagnostics. The dedicated Heidelberg Heavy Ion Cancer Therapy Project includes two ECR ion sources, a RF linear injector, a synchrotron and three treatment rooms. It will deliver 4*10 high 10 protons, or 1*10 high 10 He, or 1*10 high 9 Carbons, or 5*10 high 8 Oxygens per synchrotron cycle with the beam energy 50-430AMeV for the treatments. The RF linear injector consists of a 400AkeV RFQ and of a very compact 7AMeV IH-DTL accelerator operated at 216.816MHz. The development of the IH-DTL within the HICAT project is a great challenge with respect to the present state of the DTL art because of the following reasons: • The highest operating frequency (216.816MHz) of all IH-DTL cavities; • Extremely large cavity length to diameter ratio of about 11; • IH-DTL with three internal triplets; • The highest effective voltage gain per meter (5.5MV/m); • Very short MEBT design for the beam matching. The following achievements have been reached during the development of the IH-DTL injector for HICAT : The KONUS beam dynamics design with LORASR code fulfills the beam requirement of the HICAT synchrotron at the injection point. The simulations for the IH-DTL injector have been performed not only with a homogeneous input beam, but also with the actual particle distribution from the exit of the HICAT RFQ accelerator as delivered by the PARMTEQ code. The output longitudinal normalized emittance for 95% of all particles is 2.00AkeVns, the emittance growth is less than 24%, while the X-X’ and Y-Y’ normalized emittance are 0.77mmmrad and 0.62mmmrad, respectively. The emittance growth in X-X’ is less than 18%, and the emittance growth in Y-Y’ is less than 5%. Based on the transverse envelopes of the transported particles, the redesign of the buncher drift tubes at the RFQ high energy end has been made to get a higher transit time factor for this novel RFQ internal buncher. An optimized effective buncher gap voltage of 45.4KV has been calculated to deliver a minimized longitudinal beam emittance, while the influence of the effective buncher voltage on the transverse emittance can be neglected. Six different tuning concepts were investigated in detail while tuning the 1:2 scaled HICAT IH model cavity. ‘Volume Tuning’ by a variation of the cavity cross sectional area can compensate the unbalanced capacitance distribution in case of an extreme beta-lambda-variation along an IH cavity. ‘Additional Capacitance Plates’ or copper sheets clamped on drift tube stems are a fast way for checking the tuning sensitivity, but they will be replaced by massive copper blocks mounted on the drift tube girders finally. ‘Lens Coupling’ is an important tuning to stabilize the operation mode and to increase or decrease the coupling between neighboring sections. ‘Tube Tuning’ is the fine tuning concept and also the standard tuning method to reach the needed field distributions as well as the gap voltage distributions. ‘Undercut Tuning’ is a very sensitive tuning for the end sections and with respect to the voltage distribution balance along the structure. The different types of ‘plungers’ in the 3rd and 4th sections have different effects on the resonance frequency and on the field distribution. The different triplet stems and the geometry of the cavity end have been also investigated to reach the design field and voltage distributions. Finally, the needed uniform field distribution along the IH-DTL cavity and the corresponding effective voltage distribution were realized, the remaining maximum gap voltage difference was less than 5% for the model cavity. The several important higher order modes were also measured. The RF tuning of the IH-DTL model cavity delivers the final geometry parameters of the IH-DTL power cavity. A rectangular cavity cross section was adopted for the first time for this IH-DTL cavity. This eases the realization of the volume tuning concept in the 1st and 2nd sections. Lens coupling determines the final distance between the triplet and the girder. The triplets are mounted on the lower cavity half shell. The Microwave Studio simulations have been carried out not only for the HICAT model cavity, but also for the final geometry of the IH-DTL power cavity. The field distribution for the operation mode H110 fits to the model cavity measurement as well as the Higher Order Modes. The simulations prove the IH-DTL geometrical design. On the other hand, the precision of one simulation with 2.3 million mesh points for full cross section area and the CPU time more than 15hours on a DELL PC with Intel Pentium 4 of 2.4GHz and 2.096GRAM were exploited to their limit when calculating the real parameters for the two final machining iterations during production. The shunt impedance of the IH-DTL power cavity is estimated by comparison with the existing tanks to about 195.8MOmega/m, which fits to the simulation result of 200.3MOmega/m with reducing the conductivity to the 5.0*10 high 7 Omega-1m-1. The effective shunt impedance is 153 MOmega/m. The needed RF power is 755kW. The expected quality factor of the IH-DTL cavity is about 15600. The IH-DTL power cavity tuning measurements before cavity copper plating have been performed. The results are within the specifications. There is no doubt that the needed accuracy of the voltage distribution will be reached with the foreseen fine tuning concepts in the last steps.