The Impact of Public and Private R&D on Farmers' Production Decisions: Econometric Evidence for Midwestern States, 1960-2004

The objective of this paper is to identify the impact of public and private agriculturalresearch on multi-output multi-input profit maximizing decisions of Midwestern farmers. The mainhypothesis is that investments in public and private R&D shift outward the supply curves for cropand livestock outputs and, in some cases, reduce the demand for inputs. The study uses stateaggregate data for eight Midwestern states over 1960-2004. The own-price elasticities of demand forall inputs are shown to be negative, being larger for agricultural chemicals and energy that for farmcapital services, labor and other materials. Additional public agricultural research increases thesupply of crop and livestock outputs but biases revenue shares toward crop output. Additionalprivate R&D as in adoption of GM corn varieties shifts outward the supply curves for crops andlivestock outputs but biases revenue shares towards crop output. In contrast, an increase in theadoption of GM soybean varieties increases livestock output and deceases crop output. Publicagricultural research reduces the demand for capital services and energy and increases the demandfor agricultural chemicals, other materials, and labor. An increase in the availability of GM soybeanvarieties increases the demand for capital services, agricultural chemicals and other materials andhas weak negative effects on the demand for labor and energy. GM corn variety adoption reducesthe demand for energy but other effects are quite small.Profit function; midwest agriculture; public research; technology; GMOs; multiple-inputs multiple output; crops

Laboratory Transferability of Optimally Shaped Laser Pulses for Quantum Control

Optimal control experiments can readily identify effective shaped laser pulses, or "photonic reagents", that achieve a wide variety of objectives. For many practical applications, an important criterion is that a particular photonic reagent prescription still produce a good, if not optimal, target objective yield when transferred to a different system or laboratory, {even if the same shaped pulse profile cannot be reproduced exactly. As a specific example, we assess the potential for transferring optimal photonic reagents for the objective of optimizing a ratio of photoproduct ions from a family of halomethanes through three related experiments.} First, applying the same set of photonic reagents with systematically varying second- and third-order chirp on both laser systems generated similar shapes of the associated control landscape (i.e., relation between the objective yield and the variables describing the photonic reagents). Second, optimal photonic reagents obtained from the first laser system were found to still produce near optimal yields on the second laser system. Third, transferring a collection of photonic reagents optimized on the first laser system to the second laser system reproduced systematic trends in photoproduct yields upon interaction with the homologous chemical family. Despite inherent differences between the two systems, successful and robust transfer of photonic reagents is demonstrated in the above three circumstances. The ability to transfer photonic reagents from one laser system to another is analogous to well-established utilitarian operating procedures with traditional chemical reagents. The practical implications of the present results for experimental quantum control are discussed

Mixed membership stochastic blockmodels

Observations consisting of measurements on relationships for pairs of objects arise in many settings, such as protein interaction and gene regulatory networks, collections of author-recipient email, and social networks. Analyzing such data with probabilisic models can be delicate because the simple exchangeability assumptions underlying many boilerplate models no longer hold. In this paper, we describe a latent variable model of such data called the mixed membership stochastic blockmodel. This model extends blockmodels for relational data to ones which capture mixed membership latent relational structure, thus providing an object-specific low-dimensional representation. We develop a general variational inference algorithm for fast approximate posterior inference. We explore applications to social and protein interaction networks.Comment: 46 pages, 14 figures, 3 table

Controlled switching between paramagnetic and diamagnetic Meissner effect in Pb/Co nanocomposites

A hybrid system which consists of a superconducting (SC) Pb film (100 nm thickness) containing $\sim$1 vol% single domain ferromagnetic (FM) Co particles of mean-size $\sim$4.5 nm reveal unusual magnetic properties: (i) a controlled switching between the usual diamagnetic and the unusual paramagnetic Meissner effect in field cooling as well as in zero-field cooling experiments (ii) amplification of the positive magnetization when the sample enters the SC state below T$_c$. These experimental findings can be explained by the formation of spontaneous vortices and the possible alignment of these vortices due to the foregoing alignment of the Co particle FM moments by an external magnetic field.Comment: 5 pages, 3 figure

Retardation Terms in The One-Gluon Exchange Potential

It is pointed out that the retardation terms given in the original Fermi-Breit potential vanish in the center of mass frame. The retarded one-gluon exchange potential is rederived in this paper from the three-dimensional one-gluon exchange kernel which appears in the exact three-dimensional relativistic equation for quark-antiquark bound states. The retardation part of the potential given in the approximation of order $p^2/m^2$ is shown to be different from those derived in the previous literature. This part is off-shell and does no longer vanish in the center of mass frame

Multiscale Technicolor and the Zbb-bar Vertex

We estimate the correction to the Zbb-bar vertex arising from the exchanges of the sideways extended technicolor (ETC) boson and the flavor-diagonal ETC boson in the multiscale walking technicolor model. The obtained result is too large to explain the present data. However, if we introduce a new self- interaction for the top quark to induce the top quark condensate serving as the origin of the large top quark mass, the corrected R_b=Gamma_b/Gamma_h can be consistent with the recent LEP data. The corresponding correction to R_c=Gamma_c/Gamma_h is shown to be negligibly small.Comment: 9-page LaTex fil

The Poisson-Boltzmann Theory for Two Parallel Uniformly Charged Plates

We solve the nonlinear Poisson-Boltzmann equation for two parallel and likely charged plates both inside a symmetric elecrolyte, and inside a 2 : 1 asymmetric electrolyte, in terms of Weierstrass elliptic functions. From these solutions we derive the functional relation between the surface charge density, the plate separation, and the pressure between plates. For the one plate problem, we obtain exact expressions for the electrostatic potential and for the renormalized surface charge density, both in symmetric and in asymmetric electrolytes. For the two plate problems, we obtain new exact asymptotic results in various regimes.Comment: 17 pages, 9 eps figure