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

Are Firms Successful at Selective Hedging?

We analyze the corporate risk management policies of 44 companies in the gold mining industry. Firms tend to decrease hedging as prices move against them—behavior contrary to that predicted by risk management theory. These results, along with new survey evidence, suggest that firms attempt to time market prices, so-called selective hedging. Although estimates show a statistically significant ability of producers to favorably adjust hedge ratios, this can be attributed to sample-specific negative autocorrelation in gold prices. Economic gains to selective hedging are small, and no evidence suggests that selective hedging leads to superior operating or financial performance

Black p-Branes versus black holes in non-asymptotically flat Einstein-Yang-Mills theory

We present a class of non-asymptotically flat (NAF) charged black p-branes (BpB) with p-compact dimensions in higher dimensional Einstein-Yang-Mills theory. Asymptotically the NAF structure manifests itself as an anti-de-sitter spacetime. We determine the total mass / energy enclosed in a thin-shell located outside the event horizon. By comparing the entropies of BpB with those of black holes in same dimensions we derive transition criteria between the two types of black objects. Given certain conditions satisfied our analysis shows that BpB can be considered excited states of black holes. An event horizon $r_{+}$ versus charge square $Q^{2}$ plot \ for the BpB reveals such a transition where $r_{+}$ is related to the horizon radius $r_{h}$ of the black hole (BH) both with the common charge $$Comment: 10 pages, 1 figure, updated version. Final version to be published in EPJ

Thematic Analysis of Teacher Instructional Practices and Student Responses in Middle School Classrooms with Problem-Based Learning Environment

Problem-based learning (PBL) environment is a student-centered instructional method based on the use of ill-structured problems as a stimulus for collaborative learning. This study tried to gain an understanding of teachersΓÇÖ instructional practices and studentsΓÇÖ responses to such practices in middle school classrooms with PBL environment through qualitative analyses. A hybrid approach of inductive and deductive thematic analyses was employed and applied to field notes and transcripts of video observations of four PBL classrooms. To do so, a codebook was created based on the descriptions of roles of teachers and students in PBL classrooms in literature, and was then applied to inductive codes that emerged from the data. This study identified a number of specific instructional practices of teachers, as well as responses that students might engage in during PBL instructions. Being able to articulate these roles is an important step in helping new PBL teachers learn to facilitate student-centered classrooms

Mechanism of Hydrolysis of Octacalcium Phosphate

The chemical and structural properties of hydrolyzed octacalcium phosphate (OCP) appear to be of high relevance to tooth, bone and pathological bioapatites. Hydrolysis of synthetic well-crystallized OCP was studied at constant pH by using the pH stat method over the 6.1 to 8.6 range at 50°C and to a lesser extent at 37°C. Hydrolytic transformation proceeds according to thermodynamic requirements except for some retardation at the highest pH value as a consequence of decreased solubility of OCP which may be rate determining. The product of hydrolysis, OCP-hydrolyzate (OCPH), was characterized by chemical analysis, scanning electron microscopy, x-ray diffraction, electron microprobe (x-ray microanalysis, EDX) and solubility measurements under static and dynamic conditions. Even after prolonged hydrolysis at 50°C, the resulting product was a calcium deficient apatite with chemical composition and thermodynamic solubility properties differing from those of well-crystallized hydroxyapatite. Our overall findings provide new evidence that OCP may be a precursor phase in the formation of pathologic calcified deposits and normal biomineral, which appear to be complex hydrolyzates of OCP

Correlations between black holes formed in cosmic string breaking

An analysis of cosmic string breaking with the formation of black holes attached to the ends reveals a remarkable feature: the black holes can be correlated or uncorrelated. We find that, as a consequence, the number-of-states enhancement factor in the action governing the formation of uncorrelated black holes is twice the one for a correlated pair. We argue that when an uncorrelated pair forms at the ends of the string, the physics involved is more analogous to thermal nucleation than to particle-antiparticle creation. Also, we analyze the process of intercommuting strings induced by black hole annihilation and merging. Finally, we discuss the consequences for grand unified strings. The process whereby uncorrelated black holes are formed yields a rate which significantly improves over those previously considered, but still not enough to modify string cosmology.Comment: 11 pages, LaTeX. Final version, to appear in Phys. Rev.

Neural population partitioning and a concurrent brain-machine interface for sequential motor function

Although brain-machine interfaces (BMIs) have focused largely on performing single-targeted movements, many natural tasks involve planning a complete sequence of such movements before execution. For these tasks, a BMI that can concurrently decode the full planned sequence before its execution may also consider the higher-level goal of the task to reformulate and perform it more effectively. Using population-wide modeling, we discovered two distinct subpopulations of neurons in the rhesus monkey premotor cortex that allow two planned targets of a sequential movement to be simultaneously held in working memory without degradation. Such marked stability occurred because each subpopulation encoded either only currently held or only newly added target information irrespective of the exact sequence. On the basis of these findings, we developed a BMI that concurrently decodes a full motor sequence in advance of movement and can then accurately execute it as desired.National Institutes of Health (U.S.) (DP1 OD003646

A Real-Time Brain-Machine Interface Combining Motor Target and Trajectory Intent Using an Optimal Feedback Control Design

Real-time brain-machine interfaces (BMI) have focused on either estimating the continuous movement trajectory or target intent. However, natural movement often incorporates both. Additionally, BMIs can be modeled as a feedback control system in which the subject modulates the neural activity to move the prosthetic device towards a desired target while receiving real-time sensory feedback of the state of the movement. We develop a novel real-time BMI using an optimal feedback control design that jointly estimates the movement target and trajectory of monkeys in two stages. First, the target is decoded from neural spiking activity before movement initiation. Second, the trajectory is decoded by combining the decoded target with the peri-movement spiking activity using an optimal feedback control design. This design exploits a recursive Bayesian decoder that uses an optimal feedback control model of the sensorimotor system to take into account the intended target location and the sensory feedback in its trajectory estimation from spiking activity. The real-time BMI processes the spiking activity directly using point process modeling. We implement the BMI in experiments consisting of an instructed-delay center-out task in which monkeys are presented with a target location on the screen during a delay period and then have to move a cursor to it without touching the incorrect targets. We show that the two-stage BMI performs more accurately than either stage alone. Correct target prediction can compensate for inaccurate trajectory estimation and vice versa. The optimal feedback control design also results in trajectories that are smoother and have lower estimation error. The two-stage decoder also performs better than linear regression approaches in offline cross-validation analyses. Our results demonstrate the advantage of a BMI design that jointly estimates the target and trajectory of movement and more closely mimics the sensorimotor control system.National Institutes of Health (U.S.) (NIH grant No.DP1-0D003646-01)National Institutes of Health (U.S.) (NIH grant R01-EB006385