Legal effectiveness and external capital : the role of foreign debt

Previous research has documented weak, and sometimes conflicting, effects of legal quality on measures of firm debt. Using WorldScope data for 1,689 firms, as well as more detailed proprietary data for 315 firms across nine East Asian countries, the authors find that access to foreign financing appears to loosen borrowing constraints associated with poor legal systems. This helps resolve inconsistencies in prior findings and explains how legal protection is important for borrowing by firms. In particular, they find that legal effectiveness is important for determining the amount, maturity, and currency denomination of debt. The authors discuss several mechanisms by which firms can avoid the costs of poor legal systems with foreign borrowing. The paper contributes to the policy debate surrounding the importance of creditor rights for domestic lending.Municipal Financial Management,Banks&Banking Reform,Economic Theory&Research,Financial Intermediation,Environmental Economics&Policies

Exchange rate risk management : evidence from East Asia

The recent East Asian financial crisis provides a natural experiment for investigating foreign exchange risk management by nonfinancial corporations. During this period, the financial crisis exposed local firms to large depreciations in exchange rates and reduced access to foreign capital. The authors explore the exchange rate hedging practices of firms that hedged exposure to foreign debt in eight East Asian countries between 1996 and 1998. They identify and characterize East Asian companies that used foreign currency derivatives, documenting differences in size, financial characteristics, and exposure to domestic and foreign debt. They investigate the factors improtant in the use of foreign currency derivatives. Unlike studies of US firms, they find limited support for existing theories of optimal hedging. Instead, they find that firms use foreign earnings as a substitute for hedging with derivatives. And they find evidence that firms engage in"selective"hedging. They investigate the relative performance of hedgers during and after the crisis. They find no evidence that East Asian firms eliminated their foreign exchange exposure by using derivatives. Firms that used derivatives before the crisis performed just as poorly as nonhedgers during the crisis. After the crisis, firms that hedged performed somewhat better than nonhedgers, but this result appears to be explained by a larger post-crisis currency exposure for hedgers (an exchange rate risk premium), which had limited access to derivatives during this period.Payment Systems&Infrastructure,Financial Intermediation,Economic Theory&Research,Banks&Banking Reform,Environmental Economics&Policies,Banks&Banking Reform,Economic Theory&Research,Environmental Economics&Policies,Strategic Debt Management,Financial Intermediation

The impact of the business environment on young firm financing

This paper uses a dataset of more than 70,000 firms in over 100 countries to systematically study the use of different financing sources for new and young firms, in comparison to mature firms. The authors find that in all countries younger firms rely less on bank financing and more on informal financing. However, they also find that younger firms use more bank finance in countries with stronger rule of law and better credit information, and that the reliance of young firms on informal finance decreases with the availability of credit information. Overall, the results suggest that improvements to the legal environment and availability of credit information are disproportionately beneficial for promoting access to formal finance by young firms.Access to Finance,Debt Markets,Bankruptcy and Resolution of Financial Distress,Banks&Banking Reform,Financial Intermediation

Conodont Zonation of the Early Upper Devonian in Eastern Iowa

The type section of the Sweetland Creek Shale in Muscatine County has yielded a sequence of five distinct conodont faunas which correspond almost exactly to a zonation of the Upper Devonian Frasnian Stage by Ziegler (1962 b) in the Rhineland. In addition, the nearby Campbell\u27s Run section has produced the lower three faunas. The Sweetland Creek is equivalent in part to the Independence Formation, and is regarded as representing the southeastern extension of that unit in its true stratigraphic position above the Cedar Valley Formation

Sustaining collaborative knowledge building: continuity in virtual math teams

When virtual teams engage in knowledge building—the creation and improvement of knowledge artifacts, they can face significant challenges related to overcoming discontinuities, such as integrating the activities of multiple participants, coordinating sessions over time, and monitoring how ideas and contributions evolve. Paradoxically, these gaps emerge from the very factors that make collaborative knowledge building promising: diversity of actors, activities, and ideas engaged over time.This dissertation investigated how Virtual Math Teams (VMT) who participated in the Math Forum online community “bridged” the discontinuities emerging from their multiple episodes of collaboration over time and the related changes in participation, and explored the role that such “bridging activity” played in the teams’ knowledge building. Through Ethnomethodology-oriented interaction analysis of episodes of collaboration selected from 38 naturally-occurring, online sessions within two VMT “Spring Fests,” the following findings emerged: (a) Bridging Methods: 4 practices were central to how VMT teams sustained knowledge building: Reporting, Collective Re-membering, Projecting, and Cross-team Bridging. These practices intertwined 3 key interactional elements: Temporality, Participation, and Knowledge Artifacts. (b) Temporality: VMT teams actively constituted temporal sequences of interaction as resources to organize their collective knowledge building over time. (c) Knowledge Artifacts. Each bridging method involved the co-construction of a bridging artifact interlinking group knowledge-building activity across different episodes or collectivities. (d) Positioning: VMT teams purposely placed individual and collective participants, their history of interaction, and relevant knowledge resources relative to each other in a situated field of interaction. (e) Continuity. The interactional relationships among Temporality, Participation, and Knowledge Artifacts established through bridging were critical to establishing diachronic continuity of knowledge building for an individual team as well as the expansive continuity of a larger collective of multiple virtual teams.These findings offer a framework for understanding how online collectivities sustain knowledge building over time. This study does not represent a complete and general scheme of bridging mechanisms; however, it highlights the frequently overlooked role of constructed temporality within the situated knowledge field that VMT teams developed over time and the dialectical integration of temporality with the organization of participation and the development of knowledge artifacts.Ph.D., Information Studies -- Drexel University, 200

Sustaining collaborative knowledge building: continuity in virtual math teams

When virtual teams engage in knowledge building—the creation and improvement of knowledge artifacts, they can face significant challenges related to overcoming discontinuities, such as integrating the activities of multiple participants, coordinating sessions over time, and monitoring how ideas and contributions evolve. Paradoxically, these gaps emerge from the very factors that make collaborative knowledge building promising: diversity of actors, activities, and ideas engaged over time.This dissertation investigated how Virtual Math Teams (VMT) who participated in the Math Forum online community “bridged” the discontinuities emerging from their multiple episodes of collaboration over time and the related changes in participation, and explored the role that such “bridging activity” played in the teams’ knowledge building. Through Ethnomethodology-oriented interaction analysis of episodes of collaboration selected from 38 naturally-occurring, online sessions within two VMT “Spring Fests,” the following findings emerged: (a) Bridging Methods: 4 practices were central to how VMT teams sustained knowledge building: Reporting, Collective Re-membering, Projecting, and Cross-team Bridging. These practices intertwined 3 key interactional elements: Temporality, Participation, and Knowledge Artifacts. (b) Temporality: VMT teams actively constituted temporal sequences of interaction as resources to organize their collective knowledge building over time. (c) Knowledge Artifacts. Each bridging method involved the co-construction of a bridging artifact interlinking group knowledge-building activity across different episodes or collectivities. (d) Positioning: VMT teams purposely placed individual and collective participants, their history of interaction, and relevant knowledge resources relative to each other in a situated field of interaction. (e) Continuity. The interactional relationships among Temporality, Participation, and Knowledge Artifacts established through bridging were critical to establishing diachronic continuity of knowledge building for an individual team as well as the expansive continuity of a larger collective of multiple virtual teams.These findings offer a framework for understanding how online collectivities sustain knowledge building over time. This study does not represent a complete and general scheme of bridging mechanisms; however, it highlights the frequently overlooked role of constructed temporality within the situated knowledge field that VMT teams developed over time and the dialectical integration of temporality with the organization of participation and the development of knowledge artifacts.Ph.D., Information Studies -- Drexel University, 200

Magnetohydrodynamics dynamical relaxation of coronal magnetic fields. II. 2D magnetic X-points

We provide a valid magnetohydrostatic equilibrium from the collapse of a 2D X-point in the presence of a finite plasma pressure, in which the current density is not simply concentrated in an infinitesimally thin, one-dimensional current sheet, as found in force-free solutions. In particular, we wish to determine if a finite pressure current sheet will still involve a singular current, and if so, what is the nature of the singularity. We use a full MHD code, with the resistivity set to zero, so that reconnection is not allowed, to run a series of experiments in which an X-point is perturbed and then is allowed to relax towards an equilibrium, via real, viscous damping forces. Changes to the magnitude of the perturbation and the initial plasma pressure are investigated systematically. The final state found in our experiments is a "quasi-static" equilibrium where the viscous relaxation has completely ended, but the peak current density at the null increases very slowly following an asymptotic regime towards an infinite time singularity. Using a high grid resolution allows us to resolve the current structures in this state both in width and length. In comparison with the well known pressureless studies, the system does not evolve towards a thin current sheet, but concentrates the current at the null and the separatrices. The growth rate of the singularity is found to be tD, with 0 < D < 1. This rate depends directly on the initial plasma pressure, and decreases as the pressure is increased. At the end of our study, we present an analytical description of the system in a quasi-static non-singular equilibrium at a given time, in which a finite thick current layer has formed at the null

Twirling and Whirling: Viscous Dynamics of Rotating Elastica

Motivated by diverse phenomena in cellular biophysics, including bacterial flagellar motion and DNA transcription and replication, we study the overdamped nonlinear dynamics of a rotationally forced filament with twist and bend elasticity. Competition between twist injection, twist diffusion, and writhing instabilities is described by a novel pair of coupled PDEs for twist and bend evolution. Analytical and numerical methods elucidate the twist/bend coupling and reveal two dynamical regimes separated by a Hopf bifurcation: (i) diffusion-dominated axial rotation, or twirling, and (ii) steady-state crankshafting motion, or whirling. The consequences of these phenomena for self-propulsion are investigated, and experimental tests proposed.Comment: To be published in Physical Review Letter

Purification of a 31,000-dalton insulin-like growth factor binding protein from human amniotic fluid. Isolation of two forms with different biologic actions.

Human amniotic fluid has been shown to contain a protein that binds insulin-like growth factor I and II (IGF-I and IGF-II). Partially purified preparations of this protein have been reported to inhibit the biologic actions of the IGFs. In these studies our laboratory has used a modified purification procedure to obtain a homogeneous preparation of this protein as determined by polyacrylamide gel electrophoresis and amino acid sequence analysis. During purification the ion exchange chromatography step resulted in two peaks of material with IGF binding activity termed peaks B and C. Each peak was purified separately to homogeneity. Both peaks were estimated to be 31,000 daltons by polyacrylamide gel electrophoresis and their amino acid compositions were nearly identical. Amino acid sequence analysis showed that both peaks had identical N-terminal sequences through the first 28 residues. Neither protein had detectable carbohydrate side chains and each had a similar affinity for radiolabeled IGF-I (1.7-2.2 x 10(10) liters/mol). In contrast, these two forms had marked differences in bioactivity. Concentrations of peak C material between 2 and 20 ng/ml inhibited IGF-I stimulation of [3H]thymidine incorporation into smooth muscle cell DNA. In contrast, when peak B (100 ng/ml) was incubated with IGF-I there was a 4.4-fold enhancement of stimulation of DNA synthesis. Additionally, pure peak B was shown to adhere to cell surfaces, whereas peak C was not adherent. The non-adherent peak C inhibited IGF-I binding to its receptor and to adherent peak B. We conclude that human amniotic fluid contains two forms of IGF binding protein that have very similar physiochemical characteristics but markedly different biologic actions. Since both have similar if not identical amino acid compositions, N-terminal sequences, and do not contain carbohydrate, we conclude that they differ in some other as yet undefined post-translational modification

The Viscous Nonlinear Dynamics of Twist and Writhe

Exploiting the "natural" frame of space curves, we formulate an intrinsic dynamics of twisted elastic filaments in viscous fluids. A pair of coupled nonlinear equations describing the temporal evolution of the filament's complex curvature and twist density embodies the dynamic interplay of twist and writhe. These are used to illustrate a novel nonlinear phenomenon: ``geometric untwisting" of open filaments, whereby twisting strains relax through a transient writhing instability without performing axial rotation. This may explain certain experimentally observed motions of fibers of the bacterium B. subtilis [N.H. Mendelson, et al., J. Bacteriol. 177, 7060 (1995)].Comment: 9 pages, 4 figure