Connections and Performance in Bankers' Turnover: Better Wed over the Mixen than over the Moor

In this paper we study top executive turnover in Italian Banks over the period 1993-2001. We relate the probability of survival of top executives (Presidents, CEOs and General Managers) to bank performance and the manager’s local connections, controlling for (observable and unobservable) bank and manager characteristics by exploiting longitudinal information on bank-manager appointments. We measure the extent? of managers’ local connections by the distance between the province of the bank’s headquarters and the manager’s province of birth. We show that top managers tend to be local in the sense that the distribution of this distance is heavily skewed towards zero. On the basis of this evidence, we address two questions. First, we investigate whether connections affect the duration of the appointment at the bank. Second, we ask whether connections entrench managers at the expense of the bank’s performance. We find that connections generally increase the probabilities of managerssurviving at their banks, and that the positive effect of performance on tenure (as amply documented by the executive turnover literature) disappears once connections are taken into account. On the other hand, we provide evidence against the hypothesis that managerial connections contain information valuable for enhancing a bank’s performance. In particular, we find that highly connected boards cause the shorter survival of banks, and that those who benefit from connections are top managers themselves (mostly Presidents and General Managers). This suggests that connections may be collusion devices with which to maintain and share rents.connections, executive turnover, commercial and cooperative banks

Dissipation and Topologically Massive Gauge Theories in Pseudoeuclidean Plane

In the pseudo-euclidean metrics Chern-Simons gauge theory in the infrared region is found to be associated with dissipative dynamics. In the infrared limit the Lagrangian of 2+1 dimensional pseudo-euclidean topologically massive electrodynamics has indeed the same form of the Lagrangian of the damped harmonic oscillator. On the hyperbolic plane a set of two damped harmonic oscillators, each other time-reversed, is shown to be equivalent to a single undamped harmonic oscillator. The equations for the damped oscillators are proven to be the same as the ones for the Lorentz force acting on two particles carrying opposite charge in a constant magnetic field and in the electric harmonic potential. This provides an immediate link with Chern-Simons-like dynamics of Bloch electrons in solids propagating along the lattice plane with hyperbolic energy surface. The symplectic structure of the reduced theory is finally discussed in the Dirac constrained canonical formalism.Comment: 22 pages, LaTe

Dynamics of mtDNA introgression during species range expansion. Insights from an experimental longitudinal study

Introgressive hybridization represents one of the long-lasting debated genetic consequences of species range expansion. Mitochondrial DNA has been shown to heavily introgress between interbreeding animal species that meet in new sympatric areas and, often, asymmetric introgression from local to the colonizing populations has been observed. Disentangling among the evolutionary and ecological processes that might shape this pattern remains difficult, because they continuously act across time and space. In this context, long-term studies can be of paramount importance. Here, we investigated the dynamics of mitochondrial introgression between two mosquito species (Aedes mariae and Ae. zammitii ) during a colonization event that started in 1986 after a translocation experiment. By analyzing 1,659 individuals across 25 years, we showed that introgression occurred earlier and at a higher frequency in the introduced than in the local species, showing a pattern of asymmetric introgression. Throughout time, introgression increased slowly in the local species, becoming reciprocal at most sites. The rare opportunity to investigate the pattern of introgression across time during a range expansion along with the characteristics of our study-system allowed us to support a role of demographic dynamics in determining the observed introgression pattern

Statistical Power Supply Dynamic Noise Prediction in Hierarchical Power Grid and Package Networks

One of the most crucial high performance systems-on-chip design challenge is to front their power supply noise sufferance due to high frequencies, huge number of functional blocks and technology scaling down. Marking a difference from traditional post physical-design static voltage drop analysis, /a priori dynamic voltage drop/evaluation is the focus of this work. It takes into account transient currents and on-chip and package /RLC/ parasitics while exploring the power grid design solution space: Design countermeasures can be thus early defined and long post physical-design verification cycles can be shortened. As shown by an extensive set of results, a carefully extracted and modular grid library assures realistic evaluation of parasitics impact on noise and facilitates the power network construction; furthermore statistical analysis guarantees a correct current envelope evaluation and Spice simulations endorse reliable result

Multi-Molecule Field-Coupled Nanocomputing for the Implementation of a Neuron

In recent years, several alternatives have been proposed to face CMOS scaling problems. Among these, molecular Field-Coupled Nanocomputing is a paradigm that encodes information in the spatial charges distribution and promises to consume a minimal amount of power. In this technology, circuits have always been designed using the same molecule type, and logic functions are obtained through specific layouts. This work demonstrates that multi-molecule circuits, which use different kinds of molecules in the same layout, enhance the circuit features and set up a new way to conceive molecular Field-Coupled Nanocomputing. In particular, by inserting different molecules with specific characteristics into appropriate layout positions, it is possible to obtain an artificial neuron behavior using the Majority Voter layout

SCERPA Simulation of Clocked Molecular Field-Coupling Nanocomputing

Among all the possible technologies proposed for post-CMOS computing, molecular field-coupled nanocomputing (FCN) is one of the most promising technologies. The information propagation relies on electrostatic interactions among single molecules, overcoming the need for electron transport, significantly reducing energy dissipation. The expected working frequency is very high, and high throughput may be achieved by introducing an efficient pipeline of information propagation. The pipeline could be realized by adding an external clock signal that controls the propagation of data and makes the transmission adiabatic. In this article, we extend the Self-Consistent Electrostatic Potential Algorithm (SCERPA), previously introduced to analyze molecular circuits with a uniform clock field, to clocked molecular devices. The single-molecule is analyzed by ab initio calculations and modeled as an electronic device. Several clocked devices have been partitioned into clock zones and analyzed: the binary wire, the bus, the inverter, and the majority voter. The proposed modification of SCERPA enables linking the functional behavior of the clocked devices to molecular physics, becoming a possible tool for the eventual physical design verification of emerging FCN devices. The algorithm provides some first quantitative results that highlight the clocked propagation characteristics and provide significant feedback for the future implementation of molecular FCN circuits

Social impacts of European Protected Areas and policy recommendations.

Effective designation of Protected Areas (PAs) requires the careful consideration of their social impacts as these are perceived by people. These refer to a variety of issues such as the distribution of power, social equity, social relations and more importantly the impact of PAs on human wellbeing. A number of studies have emerged in the past decade aiming to capture social impacts of PAs across the world through non-monetary assessments taking into consideration people's perceptions. Although Europe is the region with the largest in proportion number of Protected Areas across the world it is also a region with very limited scientific evidence on this topic. As the European Union is preparing to implement its new Biodiversity Strategyto ipkmplement this paper aims to provide the first comprehensive review of the literature regarding social impacts of European PAs and highlight new directions for current policy frameworks in the region. The paper focuses on the perceived non-economic social costs and benefits of PAs and identifies 7 key categories of social impacts. We propose that policy planning for biodiversity conservation in Europe should incorporate subjective assessments of social costs and benefits with the aim to achieve an increase of benefits for people and their equal distribution across social groups

Interleaving in Systolic-Arrays: a Throughput Breakthrough

In past years the most common way to improve computers performance was to increase the clock frequency. In recent years this approach suffered the limits of technology scaling, therefore computers architectures are shifting toward the direction of parallel computing to further improve circuits performance. Not only GPU based architectures are spreading in consideration, but also Systolic Arrays are particularly suited for certain classes of algorithms. An important point in favor of Systolic Arrays is that, due to the regularity of their circuit layout, they are appealing when applied to many emerging and very promising technologies, like Quantum-dot Cellular Automata and nanoarrays based on Silicon NanoWire or on Carbon nanotube Field Effect Transistors. In this work we present a systematic method to improve Systolic Arrays performance exploiting Pipelining and Input Data Interleaving. We tackle the problem from a theoretical point of view first, and then we apply it to both CMOS technology and emerging technologies. On CMOS we demonstrate that it is possible to vastly improve the overall throughput of the circuit. By applying this technique to emerging technologies we show that it is possible to overcome some of their limitations greatly improving the throughput, making a considerable step forward toward the post-CMOS era