Probing Option Prices for Information

We present a methodology for extracting information from option prices when the market is viewed as knowledgeable. By expanding the information filtration judiciously and determining conditional characteristic functions for the log of the stock price, we obtain option pricing formulae which when fit to market data may reveal this information. In particular, we consider probing option prices for knowledge of the future stock price, instantaneous volatility, and the asymptotic dividend stream. Additionally the bridge laws developed are also useful for simulation based on stratified sampling that conditions on the terminal values of paths.      

Biodegradation of toluene in a membrane biofilter

A membrane biofilter is used to biodegrade toluene in the gas phase. Active microorganisms are immobilized on the outside of a hollow fiber membrane cartridge and air containing toluene as the contaminant is passed through the membrane fibers. A porous polysulfone membrane containing water in the pore is used through which both toluene and oxygen are diffused to the biofilm attached to the outside surface. High conversion of toluene (84%) is achieved with a 16 second gas-phase residence time, based on total internal volume of the hollow fibers. A mathematical model is then developed to estimate toluene removal efficiencies at higher air flow rates.     

An Exact Solution Algorithm for a Class of Production Planning and Scheduling Problems

This paper presents a formulation and an exact solution algorithm for a class of production planning and scheduling problems. The problem is one of optimally specifying production levels for each product in each period of the planning horizon. The objective is to minimize the sum of the set-up, regular time production, overtime and inventory holding costs. The problem has been formulated as a variation of fixed charge transportation problem. The problem discussed here is NP-hard in computational complexity. A numerical example is presented for better understanding of the algorithm.     

Bhattacharyya bound of variances of unbiased estimators in nonregular cases

Summary Bhattachayya bound is generalized to nonregular cases when the support of the density depends on the parameter, while it is differentiable several times with respect to the parameter within the support. Some example is discussed, where it is shown that the bound is sharp. Research supported by NSF Grant MCS-8301409.     

Dense solutions to the Cauchy problem for minimal surfaces

We show a general way to produce in explicit coordinates complete minimal surfaces in ³ that lie densely in the whole space. This construction relies on solving the Björling problem for adequate initial data.1 Partially supported by MCYT-FEDER, Grant no. BFM2001-3318.2 Partially supported byMCYT-FEDER, Grant no. BFM2001-2871 and CARM Programa Séneca, Grant no PI-3/00854/FS/01.     

Lactic acid bacteria used in inoculants for silage as probiotics for ruminants

Many studies have shown the beneficial effects on ruminant performance of feeding them with silages inoculated with lactic acid bacteria (LAB). These benefits might derive from probiotic effects. The purpose of the current study was to determine whether LAB included in inoculants for silage can survive in rumen fluid (RF), as the first step in studying their probiotic effects. Experiments were conducted in the United States and Israel with clarified (CRF) and strained RF (SRF) that were inoculated at 10⁶–10⁸ microorganisms/mL with and without glucose at 5 g/L. RF with no inoculants served as control. Ten commercial inoculants were used. The RF was incubated at 39°C and sampled in duplicates at 6, 12, 24, 48, 72, and 96 h for pH and LAB counts. The results indicate that with glucose the pH of the RF decreased during the incubation period. In the SRF, the pH of the inoculated samples was higher than that of the controls in most cases. This might be a clue to the mechanism by which LAB elicit the enhancement in animal performance. LAB counts revealed that the inoculants survived in the RF during the incubation period. The addition of glucose resulted in higher LAB counts.     

Hierarchical radiative masses in a supersymmetric three-family model without higgsinos

We study the scalar potential and the mass spectrum of the supersymmetric extension of a three-family model based on the local gauge group , with anomalies canceled among the three families in a non-trivial fashion. In this model the slepton multiplets play the role of the Higgs scalars and no higgsinos are required, with the consequence that the sneutrino, the selectron and six other sleptons play the role of the Goldstone bosons of the theory. By introducing an Abelian anomaly-free discrete symmetry and aligning the vacuum in a convenient way, we get a consistent mass spectrum for the scalars and for the spin 1/2 quarks and charged leptons, where only the top and charm quarks and the tau lepton acquire tree-level masses while the remaining ordinary charged fermions acquire radiative hierarchical masses.Received: 9 August 2004, Revised: 10 March 2005, Published online: 8 June 2005PACS: 12.60.Jv, 12.60.Cn, 12.15.Ff     

From azides to nitro compounds in a few seconds using HOF.CH3CN

HOF.CH3CN, a very efficient oxygen-transfer agent, was reacted with various azides to form the corresponding nitro compounds in excellent yields and in very short reaction times. The respective nitroso derivatives were found to be intermediates in this reaction. When the azides were reacted with MCPBA or DMDO, no reaction took place, and the starting materials were fully recovered.     

Shape and phase transitions in quantum-Hall skyrmions

The shape deformability of quantum-Hall skyrmions leads to a rich phase diagram in the –g space. We study the long-wavelength physics of a collection of interacting skyrmions using a nonlinear sigma model. At zero temperature the ground state is crystalline with generalized Nèel order. As a function of the filling factor , the skyrmion crystal undergoes a sequence of structural transitions driven by a change of shape of the individual skyrmions. Quantum effects lead to melting and orientational disordering transitions at high and low skyrmion densities, respectively. We show that moment of inertia of skyrmions also arises from the shape deformability of the skyrmions.