Heart of Darkness: Modeling Public-Private Funding Interactions Inside the R&D Black Box

This paper is a first step toward closing the analytical gap in the extensive literature on the results of interactions between public and private R&D expenditures, and their joint effects on the economy. Econometric studies in this area report a plethora of sometimes confusing and frequently contradictory estimates of the response of company financed R&D to changes in the level and nature of public R&D expenditure, but the necessary theoretical framework within which the empirical results can be interpreted is seldom provided. A major cause of inconsistencies' in the empirical literature is the failure to recognize key differences among the various policy experiments' being considered depending upon the economy in which they are embedded, and the type of public sector R&D spending that is contemplated. Using a simple, stylized structural model, we identify the main channels of impact of public R&D. We thus can characterize the various effects, distinguishing between short-run and long-run impacts that would show up in simple regression analyses of nominal public and private R&D expenditure variables. Within the context of our simple model it is possible to offer interpretations that shed light on recent cross-section and panel data findings at both high (i.e. national) and low (specific technology area) levels of aggregation.

Heart of Darkness: Modeling Public-Private Funding Interactions Inside the R&D Black Box

This paper is a first step toward closing the analytical gap in the extensive literature on the results of interactions between public and private R&D expenditures, and their joint effects on the economy. Earlier studies frequently report contradictory estimates of the response of company financed R&D to changes in the level and nature of public R&D expenditure. A major cause of "inconsistencies" in the empirical literature is the failure to recognize key differences among the various policy "experiments" being considered depending upon the economy in which they are embedded, and the type of public sector R&D spending that is contemplated. Using a simple, stylized structural model, we identify the main channels of impact of public R&D and characterize the various effects, distinguishing between short-run and long-run impacts that would show up in simple regression analyses of nominal public and private R&D expenditure variables. We offer interpretations that shed light on recent cross-section and panel data findings at both high (i.e. national) and low (specific technology area) levels of aggregation.

A strong form of the Quantitative Isoperimetric inequality

We give a refinement of the quantitative isoperimetric inequality. We prove that the isoperimetric gap controls not only the Fraenkel asymmetry but also the oscillation of the boundary

A Survey for Outer Satellites of Mars: Limits to Completeness

We surveyed the Hill sphere of Mars for irregular satellites. Our search covered nearly the entire Hill Sphere, but scattered light from Mars excluded the inner few arcminutes where the satellites Phobos and Deimos reside. No new satellites were found to an apparent limiting red magnitude of 23.5, which corresponds to radii of about 0.09 km using an albedo of 0.07.Comment: 5 figures (1 color), 2 Tables, to appear in AJ Nov. 200

Quantum probe hyperpolarisation of molecular nuclear spins

The hyperpolarisation of nuclear spins within target molecules is a critical and complex challenge in magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) spectroscopy. Hyperpolarisation offers enormous gains in signal and spatial resolution which may ultimately lead to the development of molecular MRI and NMR. At present, techniques used to polarise nuclear spins generally require low temperatures and/or high magnetic fields, radio-frequency control fields, or the introduction of catalysts or free-radical mediators. The emergence of room temperature solid-state spin qubits has opened exciting new pathways to circumvent these requirements to achieve direct nuclear spin hyperpolarisation using quantum control. Employing a novel cross-relaxation induced polarisation (CRIP) protocol using a single nitrogen-vacancy (NV) centre in diamond, we demonstrate the first external nuclear spin hyperpolarisation achieved by a quantum probe, in this case of $^1$H molecular spins in poly(methyl methacrylate). In doing so, we show that a single qubit is capable of increasing the thermal polarisation of $\sim 10^6$ nuclear spins by six orders of magnitude, equivalent to an applied magnetic field of $10^5$\,T. The technique can also be tuned to multiple spin species, which we demonstrate using both \C{13} and $^1$H nuclear spin ensembles. Our results are analysed and interpreted via a detailed theoretical treatment, which is also used to describe how the system can be scaled up to a universal quantum hyperpolarisation platform for the production of macroscopic quantities of contrast agents at high polarisation levels for clinical applications. These results represent a new paradigm for nuclear spin hyperpolarisation for molecular imaging and spectroscopy, and beyond into areas such as materials science and quantum information processing.Comment: 6 pages, 4 figure

Speciation in the baboon and its relation to gamma-chain heterogeneity and to the response to induction of HbF by 5-azacytidine

In the baboon (Papio species), the two nonallelic gamma-genes produce gamma-chains that differ at a minimum at residue 75, where isoleucine (I gamma-chain) or valine (V gamma) may be present. This situation obtains in baboons that are sometimes designated as Papio anubis, Papio hamadryas, and Papio papio. However, in Papio cynocephalus, although the I gamma-chains are identical with those in the above mentioned types, the V gamma-chains have the substitutions ala----gly at residue 9 and ala----val at residue 23. The V gamma-chains of P. cynocephalus are called V gamma C to distinguish them from the V gamma A-chains of P. anubis, etc. A single cynocephalus animal has been found to have only normal I gamma-chains and I gamma C-chains (that is, glycine in residue 9, valine in 23, and isoleucine in 75). When HbF is produced in response to stress with 5-azacytidine, P. anubis baboons respond with greater production than do P. cynocephalus, and hybrids fall between. Minimal data on P. hamadryas and P. papio suggest an even lower response than P. cynocephalus. As HbF increases under stress, the ratio of I gamma to V gamma-chains changes from the value in the adult or juvenile baboon toward the ratio in the newborn baboon. However, it does not attain the newborn value. The V gamma A and V gamma C-genes respond differently to stress. In hybrids, the production of V gamma A- chains exceeds that of V gamma C-chains. A controlling factor in cis apparently is present and may be responsible for the species-related extent of total HbF production. It may be concluded that the more primitive the cell in the erythroid maturation series that has been subjected to 5-azacytidine, the more active is the I gamma-gene

Field evaluation of potential pheromone lures for Lygus lineolaris (Hemiptera: Miridae) in the Mid-South

Field screening of lures in the Midsouth USA indicated that the lure containing hexyl butyrate, (E)-2-hexenyl butyrate and (E)-4-oxo-2-hexenal(4:10:7) was the most effective at collecting Lygus lineolaris, and collected similar numbers of individuals to traps baited with live virgin insects over a similar period of time in other studies