Sectoral Shocks and Structural Unemployment

When current employers rave more information about worker quality than to potential employers, sectoral shocks cause structural unemployment. That is, some workers laid off from an injured sector remain unemployed despite the fact that trey are of sufficient quality to be productively employed in an expanding sector at toe prevailing wage, Moreover, sectoral unemployment rates are not monotonic in one severity of sectoral shocks due to one interaction of layoff activity and hiring activity. Finally, equilibrium employment decisions are not constrained Pareto efficient, and can be improved by a policy of adjustment assistance.

Measuring the Relative Performance of Providers of a Health Service

A methodology is developed and applied to compare the performance of publicly funded agencies providing treatment for alcohol abuse in Maine. The methodology estimates a Wiener process that determines the duration of completed treatments, while allowing for agency differences in the effectiveness of treatment, standards for completion of treatment, patient attrition, and the characteristics of patient populations. Notably, the Wiener process model separately identifies agency fixed effects that describe differences in the effectiveness of treatment ('treatment effects'), and effects that describe differences in the unobservable characteristics of patients ('population effects'). The estimated model enables hypothetical comparisons of how different agencies would treat the same populations. The policy experiment of transferring the treatment practices of more cost-effective agencies suggests that Maine could have significantly reduced treatment costs without compromising health outcomes by identifying and transferring best practices.

Profitability of Product Bundling

Using copulas to model the stochastic dependence of values, this paper establishes new general conditions on the profitability of product bundling. A multiproduct monopolist generally achieves higher profit from mixed bundling than from separate selling if consumer values for two products are negatively dependent, independent, or have limited positive dependence. With more than two goods, the same conditions are sufficient for an optimal monopoly selling scheme to include a bundle of at least two products. The profitability of monopoly bundling also extends to situations where a multiproduct firm competes with a single-product rival

Price-increasing competition

In a discrete choice model of product differentiation, the symmetric duopoly price may be lower than, equal to, or higher than the single-product monopoly price. While the market share effect of competition encourages a firm to charge less than the monopoly price because a duopolist serves fewer consumers, the price sensitivity effect of competition motivates a higher price when more consumer choice steepens the firm's demand curve. The joint distribution of consumer values for the two conceivable products determines the relative strength of these effects, and whether presence of a symmetric competitor results in a higher or lower price compared to single-product monopoly. The analysis reveals that rice-increasing competition is unexceptional from a theoretical perspective

A New Symmetric Expression of Weyl Ordering

For the creation operator \adag and the annihilation operator $a$ of a harmonic oscillator, we consider Weyl ordering expression of (\adag a)^n and obtain a new symmetric expression of Weyl ordering w.r.t. \adag a \equiv N and a\adag =N+1 where $N$ is the number operator. Moreover, we interpret intertwining formulas of various orderings in view of the difference theory. Then we find that the noncommutative parameter corresponds to the increment of the difference operator w.r.t. variable $N$. Therefore, quantum (noncommutative) calculations of harmonic oscillators are done by classical (commutative) ones of the number operator by using the difference theory. As a by-product, nontrivial relations including the Stirling number of the first kind are also obtained.Comment: 15 pages, Latex2e, the title before replacement is "Orderings of Operators in Quantum Physics", new proofs by using a difference operator added, some references added, to appear in Modern Physics Letters

Product improvement and technological tying in a winner-take-all market

In a winner-take-all duopoly market for systems in which firms invest to improve their products, a monopoly supplier of an essential system component may have an incentive to advantage itself by technological tying; that is, by designing the component to work better in its own system. If the vertically integrated firm is prevented from technologically tying, then there is a pure strategy equilibrium in which the more efficient firm invests and serves the entire market. However other equilibria may exist, including a pure strategy equilibrium in which the less efficient firm invests and captures the market and mixed strategy equilibria in which each firm captures the market with positive probability. In contrast, if the vertically integrated firm is able to degrade the quality of its rival's system with a technological tie, and if the wholesale price of the essential component is insufficiently remunerative, then there is a unique equilibrium outcome in which the supplier of the essential component invests alone and forecloses a more efficient rival with an actual, or merely threatened, technological tie. A comparison of these equilibria for the two game forms demonstrates that a prohibition of technological tying can either increase or decrease social welfare depending on equilibrium selection

Voltage-dependent Block of the Cystic Fibrosis Transmembrane Conductance Regulator Cl- Channel by Two Closely Related Arylaminobenzoates

The gene defective in cystic fibrosis encodes a Cl- channel, the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR is blocked by diphenylamine-2-carboxylate (DPC) when applied extracellularly at millimolar concentrations. We studied the block of CFTR expressed in Xenopus oocytes by DPC or by a closely related molecule, flufenamic acid (FFA). Block of whole-cell CFTR currents by bath-applied DPC or by FFA, both at 200 µM, requires several minutes to reach full effect. Blockade is voltage dependent, suggesting open-channel block: currents at positive potentials are not affected but currents at negative potentials are reduced. The binding site for both drugs senses ~40% of the electric field across the membrane, measured from the inside. In single-channel recordings from excised patches without blockers, the conductance was 8.0 ± 0.4 pS in symmetric 150 mM Cl^-. A subconductance state, measuring ~60% of the main conductance, was often observed. Bursts to the full open state lasting up to tens of seconds were uninterrupted at depolarizing membrane voltages. At hyperpolarizing voltages, bursts were interrupted by brief closures. Either DPC or FFA (50 µM) applied to the cytoplasmic or extracellular face of the channel led to an increase in flicker at V_m =-100 mV and not at V_m = +100 mV, in agreement with whole-cell experiments. DPC induced a higher frequency of flickers from the cytoplasmic side than the extracellular side. FFA produced longer closures than DPC; the FFA closed time was roughly equal (~ 1.2 ms) at -100 mV with application from either side. In cell-attached patch recordings with DPC or FFA applied to the bath, there was flickery block at V_m = -100 mV, confirming that the drugs permeate through the membrane to reach the binding site. The data are consistent with the presence of a single binding site for both drugs, reached from either end of the channel. Open-channel block by DPC or FFA may offer tools for use with site-directed mutagenesis to describe the permeation pathway

Sensitivity of an image plate system in the XUV (60 eV < E < 900 eV)

Phosphor imaging plates (IPs) have been calibrated and proven useful for quantitative x-ray imaging in the 1 to over 1000 keV energy range. In this paper we report on calibration measurements made at XUV energies in the 60 to 900 eV energy range using beamline 6.3.2 at the Advanced Light Source at Lawrence Berkeley National Laboratory. We measured a sensitivity of ~25 plus or minus 15 counts/pJ over the stated energy range which is compatible with the sensitivity of Si photodiodes that are used for time-resolved measurements. Our measurements at 900 eV are consistent with the measurements made by Meadowcroft et al. at ~1 keV.Comment: 7 pages, 2 figure

Cytotoxicity of ascorbate, lipoic acid, and other antioxidants in hollow fibre in vitro tumours

Vitamin C (ascorbate) is toxic to tumour cells, and has been suggested as an adjuvant cancer treatment. Our goal was to determine if ascorbate, in combination with other antioxidants, could kill cells in the SW620 hollow fibre in vitro solid tumour model at clinically achievable concentrations. Ascorbate anti-cancer efficacy, alone or in combination with lipoic acid, vitamin K 3, phenyl ascorbate, or doxorubicin, was assessed using annexin V staining and standard survival assays. 2-day treatments with 10 mM ascorbate increased the percentage of apoptotic cells in SW620 hollow fibre tumours. Lipoic acid synergistically enhanced ascorbate cytotoxicity, reducing the 2-day LC 50 in hollow fibre tumours from 34 mM to 4 mM. Lipoic acid, unlike ascorbate, was equally effective against proliferating and non-proliferating cells. Ascorbate levels in human blood plasma were measured during and after intravenous ascorbate infusions. Infusions of 60 g produced peak plasma concentrations exceeding 20 mM with an area under the curve (24 h) of 76 mM h. Thus, tumoricidal concentrations may be achievable in vivo. Ascorbate efficacy was enhanced in an additive fashion by phenyl ascorbate or vitamin K 3. The effect of ascorbate on doxorubicin efficacy was concentration dependent; low doses were protective while high doses increased cell killing. © 2001 Cancer Research Campaign http://www.bjcancer.co

A probabilistic approach to some results by Nieto and Truax

In this paper, we reconsider some results by Nieto and Truax about generating functions for arbitrary order coherent and squeezed states. These results were obtained using the exponential of the Laplacian operator; more elaborated operational identities were used by Dattoli et al. \cite{Dattoli} to extend these results. In this note, we show that the operational approach can be replaced by a purely probabilistic approach, in the sense that the exponential of derivatives operators can be identified with equivalent expectation operators. This approach brings new insight about the kinks between operational and probabilistic calculus.Comment: 2nd versio