Institutional environment, innovative entrepreneurial entry and venture capital financing

We analyse the determinants of high growth expectations entrepreneurial entry (HGE) using individual data drawn on working age population, based on the Global Entrepreneurship Monitor (GEM) surveys for the 1998-2004 period. Individual level explanatory variables are combined with country-level factors. Our results suggest that availability of venture capital and intellectual proper rights protection are strong predictors of HGE. In addition, we also find that innovative start-ups are associated with highest growth expectations in countries with extensive supply of venture capital and strongest intellectual property rights. Once we introduce venture capital, we detect no significant effects of other elements of financial systems on high-powered entry

Light-cone sum rules: A SCET-based formulation

We describe the construction of light-cone sum rules (LCSRs) for exclusive $B$-meson decays into light energetic hadrons from correlation functions within soft-collinear effective theory (SCET). As an example, we consider the SCET sum rule for the $B \to \pi$ transition form factor at large recoil, including radiative corrections from hard-collinear loop diagrams at first order in the strong coupling constant.Comment: LaTex, 4 pages, 2 eps figures. Talk given at QCD05, 12th International QCD Conference, 4-9th July 2005, Montpellier, Franc

Connectionist simulation of attitude learning: Asymmetries in the acquisition of positive and negative evaluations

Connectionist computer simulation was employed to explore the notion that, if attitudes guide approach and avoidance behaviors, false negative beliefs are likely to remain uncorrected for longer than false positive beliefs. In Study 1, the authors trained a three-layer neural network to discriminate "good" and "bad" inputs distributed across a two-dimensional space. "Full feedback" training, whereby connection weights were modified to reduce error after every trial, resulted in perfect discrimination. "Contingent feedback," whereby connection weights were only updated following outputs representing approach behavior, led to several false negative errors (good inputs misclassified as bad). In Study 2, the network was redesigned to distinguish a system for learning evaluations from a mechanism for selecting actions. Biasing action selection toward approach eliminated the asymmetry between learning of good and bad inputs under contingent feedback. Implications for various attitudinal phenomena and biases in social cognition are discussed

Ultra-low dissipation Josephson transistor

A superconductor-normal metal-superconductor (SNS) transistor based on superconducting microcoolers is presented. The proposed 4-terminal device consists of a long SNS Josephson junction whose N region is in addition symmetrically connected to superconducting reservoirs through tunnel barriers (I). Biasing the SINIS line allows to modify the quasiparticle temperature in the weak link, thus controlling the Josephson current. We show that, in suitable voltage and temperature regimes, large supercurrent enhancements can be achieved with respect to equilibrium, due to electron ``cooling'' generated by the control voltage. The extremely low power dissipation intrinsic to the structure makes this device relevant for a number of electronic applications.Comment: 4 pages, 3 figures, to appear in Applied Physics Letter

Measuring von Neumann entanglement entropies without wave functions

We present a method to measure the von Neumann entanglement entropy of ground states of quantum many-body systems which does not require access to the system wave function. The technique is based on a direct thermodynamic study of entanglement Hamiltonians, whose functional form is available from field theoretical insights. The method is applicable to classical simulations such as quantum Monte Carlo methods, and to experiments that allow for thermodynamic measurements such as the density of states, accessible via quantum quenches. We benchmark our technique on critical quantum spin chains, and apply it to several two-dimensional quantum magnets, where we are able to unambiguously determine the onset of area law in the entanglement entropy, the number of Goldstone bosons, and to check a recent conjecture on geometric entanglement contribution at critical points described by strongly coupled field theories

Influence of the pair coherence on the charge tunneling through a quantum dot connected to a superconducting lead

We analyze the charge transport through a single level quantum dot coupled to a normal (N) and superconducting (S) leads where the electron pairs exist either as the coherent (for temperatures below T_c) or incoherent objects (in a region T_c < T < T*). This situation can be achieved in practice if one uses the high T_c superconducting material where various precursor effects have been observed upon approaching $T_{c}$ from above. Without restricting to any particular microscopic mechanism we investigate some qualitative changes of the nonequilibrium charge current caused by the electron pair coherence.Comment: 7 pages, 9 figure

What Makes Informal Leaders Tick? An Examination of Their Leadership Experience

Although research about informal leadership continues to expand, there is still a lack of understanding about the role of the informal leader and their leadership experience. This Capstone seeks to understand informal leadership directly from informal leaders, which is currently a gap in the literature. My research question, “How do informal leaders view and understand their role as informal leaders?” is examined in this exploratory study. A qualitative research methodology was used as the framework for 18 semi-structured interviews of the informal leader participants. Purposeful sampling was used to select participants for the study. Thematic coding was used to analyze the interview data. The prominent themes from the data indicated that formal leaders exert influence on informal leaders in ways that informal leaders consider to be at times supportive and positive, and at other times undermining. Informal leaders are motivated by feeling that they are contributing to the greater good of the organization. Informal leaders are often viewed as the “go-to” person and this can be satisfying, risky, or both. The study found that although informal leaders find aspects of informal leadership challenging, in some cases due to lack of support for or clarity about their role, they also want to learn more about this form of leadership. Curiosity about this form of leadership from informal leaders is spurred by their interest in knowing more about their leadership style, as well as the ability to identify other informal leaders. Additionally, informal leaders often play a central and positive role in organizations due to their ability to collaborate, form relationships, and work across multiple levels of the enterprise

Tailoring Josephson coupling through superconductivity-induced nonequilibrium

The distinctive quasiparticle distribution existing under nonequilibrium in a superconductor-insulator-normal metal-insulator-superconductor (SINIS) mesoscopic line is proposed as a novel tool to control the supercurrent intensity in a long Josephson weak link. We present a description of this system in the framework of the diffusive-limit quasiclassical Green-function theory and take into account the effects of inelastic scattering with arbitrary strength. Supercurrent enhancement and suppression, including a marked transition to a $\pi$-junction are striking features leading to a fully tunable structure.Comment: 4 pages, 4 figure

Mesoscopic supercurrent transistor controlled by nonequilibrium cooling

The distinctive quasiparticle distribution existing under nonequilibrium in a superconductor-insulator-normal metal-insulator-superconductor (SINIS) mesoscopic line is proposed as a novel tool to control the supercurrent intensity in a long Josephson weak link. We present a description of this system in the framework of the diffusive-limit quasiclassical Green-function theory and take into account the effects of inelastic scattering with arbitrary strength. Supercurrent enhancement and suppression, including a marked transition to a $\pi$-junction are striking features leading to a fully tunable structure. The role of the degree of nonequilibrium, temperature, and materials choice as well as features like noise, switching time, and current and power gain are also addressed.Comment: 8 pages, 9 figures, submitted to Journal of Low Temperature Physic