Who Benefits from New Medical Technologies? Estimates of Consumer and Producer Surpluses for HIV/AIDS Drugs

The social value of an innovation is comprised of the value to consumers and the value to innovators. We estimate that for the HIV/AIDS therapies that entered the market from the late 1980's onwards, innovators appropriated only 5% of the social surplus arising from these new technologies. Despite the high annual costs of these drugs to patients, the low share of social surplus going to innovators raises concerns about advocating cost-effectiveness criteria that would further reduce this share, and hence further reduce incentives for innovation.

Surplus Appropriation from R&D and Health Care Technology Assessment Procedures

Given the rapid growth in health care spending that is often attributed to technological change, many private and public institutions are grappling with how to best assess and adopt new health care technologies. The leading technology adoption criteria proposed in theory and used in practice involve so called "cost-effectiveness" measures. However, little is known about the dynamic efficiency implications of such criteria, in particular how they influence the R&D investments that make technologies available in the first place. We argue that such criteria implicitly concern maximizing consumer surplus, which many times is consistent with maximizing static efficiency after an innovation has been developed. Dynamic efficiency, however, concerns aligning the social costs and benefits of R&D and is therefore determined by how much of the social surplus from the new technology is appropriated as producer surplus. We analyze the relationship between cost-effectiveness measures and the degree of surplus appropriation by innovators driving dynamic efficiency. We illustrate how to estimate the two for the new HIV/AIDS therapies that entered the market after the late 1980's and find that only 5% of the social surplus is appropriated by innovators. We show how this finding can be generalized to other existing cost-effectiveness estimates by deriving how those estimates identify innovator appropriation for a set of studies of over 200 drugs. We find that these studies implicitly support a low degree of appropriation as well. Despite the high annual cost of drugs to patients, very low shares of social surplus may go to innovators, which may imply that cost-effectiveness is too high in a dynamic efficiency sense.

Charged basal stacking fault (BSF) scattering in nitride semiconductors

A theory of charge transport in semiconductors in the presence of basal stacking faults is developed. It is shown that the presence of basal stacking faults leads to anisotropy in carrier transport. The theory is applied to carrier transport in non-polar GaN films consisting of a large number BSFs, and the result is compared with experimental data.Comment: 4 pages, 3 figure

Topical administration of adrenergic receptor pharmaceutics and nerve growth factor

Topical application of nerve growth factor (NGF) and adrenergic receptor pharmaceutics are currently in use for corneal ulcers and glaucoma. A recent interest in the neuroprotective abilities of NGF has led to a renewed interest in NGF as a therapeutic for retinal and choroidal diseases. NGF can promote cell proliferation through actions of the TrkA receptor or promote apoptosis through receptor p75NTR. This understanding has led to novel interest in the role of NGF for diseases of the posterior eye. The role of β-adrenergic receptor agonists and antagonists for treatments of glaucoma, diabetic retinopathy, and their potential mechanisms of action, are still under investigation. This review discusses the current knowledge and applications of topical NGF and adrenergic receptor drugs for ocular disease

Hippocampal Infusion of Zeta Inhibitory Peptide Impairs Recent, but Not Remote, Recognition Memory in Rats.

Spatial memory in rodents can be erased following the infusion of zeta inhibitory peptide (ZIP) into the dorsal hippocampus via indwelling guide cannulas. It is believed that ZIP impairs spatial memory by reversing established late-phase long-term potentiation (LTP). However, it is unclear whether other forms of hippocampus-dependent memory, such as recognition memory, are also supported by hippocampal LTP. In the current study, we tested recognition memory in rats following hippocampal ZIP infusion. In order to combat the limited targeting of infusions via cannula, we implemented a stereotaxic approach for infusing ZIP throughout the dorsal, intermediate, and ventral hippocampus. Rats infused with ZIP 3-7 days after training on the novel object recognition task exhibited impaired object recognition memory compared to control rats (those infused with aCSF). In contrast, rats infused with ZIP 1 month after training performed similar to control rats. The ability to form new memories after ZIP infusions remained intact. We suggest that enhanced recognition memory for recent events is supported by hippocampal LTP, which can be reversed by hippocampal ZIP infusion

Role of Self-Interaction Effects in the Geometry Optimization of Small Metal Clusters

By combining the Self-Interaction Correction (SIC) with pseudopotential perturbation theory, the role of self-interaction errors inherent to the Local Density Approximation (LDA) to Density Functional Theory is estimated in the determination of ground state and low energy isomeric structures of small metallic clusters. Its application to neutral sodium clusters with 8 and 20 atoms shows that the SIC provides sizeable effects in Na_8, leading to a different ordering of the low lying isomeric states compared with ab-initio LDA predictions, whereas for Na_20, the SIC effects are less pronounced, such that a quantitative agreement is achieved between the present method and ab-initio LDA calculations.Comment: RevTeX, 4 pages, 1 figure available from [email protected]

Effect of high-K dielectrics on charge transport in graphene

The effect of various dielectrics on charge mobility in single layer graphene is investigated. By calculating the remote optical phonon scattering arising from the polar substrates, and combining it with their effect on Coulombic impurity scattering, a comprehensive picture of the effect of dielectrics on charge transport in graphene emerges. It is found that though high-$\kappa$ dielectrics can strongly reduce Coulombic scattering by dielectric screening, scattering from surface phonon modes arising from them wash out this advantage. By comparing the room-temperature transport properties with narrow-bandgap III-V semiconductors, strategies to improve the mobility in single layer graphene are outlined.Comment: 6 pages, 4 Figure

Environmental Issues in Indian Freshwater Aquaculture

Aquaculture is assuming increasing importance in recent years on a global basis including the Indian subcontinent. With possibilities of obtaining high productivity levels among different farming system, there has been a flux between the farming practices and aquaculture is receiving greater investments both in public and private secto

SU(2) Chiral Sigma Model Study of Phase Transition in Hybrid Stars

We use a modified SU(2) chiral sigma model to study nuclear matter component and simple bag model for quark matter constituting a neutron star. We also study the phase transition of nuclear matter to quark matter with the mixed phase characterized by two conserved charges in the interior of highly dense neutron stars. Stable solutions of Tolman-Oppenheimer-Volkoff equations representing hybrid stars are obtained with a maximum mass of 1.67$M_{\odot}$ and radius around 8.9 km.Comment: 14 pages, 5 figure