Economic Growth and the Diffusion of Clean Technologies: Explaining Environmental Kuznets Curves

Production often causes pollution as a by-product. Once environmental degradation becomes too severe, regulation is introduced by which society forces the economy to make a transition to cleaner production processes. We model this transition as a change in general purpose technology" and investigate how it interferes with economic growth driven by quality-improvements. The model gives an explanation for the inverted U-shaped pollution-income relation found in empirical research for many pollutants (Environmental Kuznets Curve). We provide an analytical foundation for the claim that the rise and decline of pollution can be explained by policy-induced technology shifts and intrasectoral changes

Strong gravitational lensing probes of the particle nature of dark matter

There is a vast menagerie of plausible candidates for the constituents of dark matter, both within and beyond extensions of the Standard Model of particle physics. Each of these candidates may have scattering (and other) cross section properties that are consistent with the dark matter abundance, BBN, and the most scales in the matter power spectrum; but which may have vastly different behavior at sub-galactic "cutoff" scales, below which dark matter density fluctuations are smoothed out. The only way to quantitatively measure the power spectrum behavior at sub-galactic scales at distances beyond the local universe, and indeed over cosmic time, is through probes available in multiply imaged strong gravitational lenses. Gravitational potential perturbations by dark matter substructure encode information in the observed relative magnifications, positions, and time delays in a strong lens. Each of these is sensitive to a different moment of the substructure mass function and to different effective mass ranges of the substructure. The time delay perturbations, in particular, are proving to be largely immune to the degeneracies and systematic uncertainties that have impacted exploitation of strong lenses for such studies. There is great potential for a coordinated theoretical and observational effort to enable a sophisticated exploitation of strong gravitational lenses as direct probes of dark matter properties. This opportunity motivates this white paper, and drives the need for: a) strong support of the theoretical work necessary to understand all astrophysical consequences for different dark matter candidates; and b) tailored observational campaigns, and even a fully dedicated mission, to obtain the requisite data.Comment: Science white paper submitted to the Astro2010 Decadal Cosmology & Fundamental Physics Science Frontier Pane

A geometric method for automatic extraction of sulcal fundi

Sulcal fundi are 3D curves that lie in the deepest regions of the cerebral cortex. Sulcal fundi are often used as landmarks for downstream computations in brain imaging. We present a sequence of geometric algorithms to automatically extract the sulcal fundi from magnetic resonance images and represent them as smooth polylines lying on the cortical surface. First we compute a geodesic depth measure for each point on the cortical surface. Based on the depth information, we extract sulcal regions by checking the connectivity above some depth threshold. We extract endpoints of the fundi and then compute the sulcal fundi by thinning each connected region with the endpoints fixed. The so found curves are then smoothed using weighted splines on surfaces to yield a high quality representation of the sulcal fundi. 1

Impact of the canine double-deletion β1 adrenoreceptor polymorphisms on protein structure and heart rate response to atenolol, a β1-selective β-blocker

Objective: [beta]-Adrenergic receptor antagonists are widely utilized for the management of cardiac diseases in dogs. We have recently identified two deletion polymorphisms in the canine adrenoreceptor 1 (ADRB1) gene. We hypothesized that canine ADRB1 deletions would alter the structure of the protein, as well as the heart rate response to the [beta]-adrenergic receptor antagonist, atenolol. The objectives of this study were to predict the impact of these deletions on the predicted structure of the protein and on the heart rate response to atenolol in a population of healthy adult dogs. Methods: Eighteen apparently healthy, mature dogs with (11) and without (seven) ADRB1 deletions were evaluated. The heart rate of the dogs was evaluated with a baseline ambulatory ECG before and 14–21 days after atenolol therapy (1 mg/kg orally q12 h). Minimum, average, and maximum heart rates were compared between groups of dogs (deletions, controls) using an unpaired t-test and within each group of dogs using a paired t-test. The protein structure of ADRB1 was predicted by computer modeling. Results: Deletions were predicted to alter the structure of the ADRB1 protein. The heart rates of the dogs with deletions were lower than those of the control dogs (the average heart rates were significantly lower). Conclusion: ADRB1 deletions appear to have structural and functional consequences. Individual genome-based treatment recommendations could impact the management of dogs with heart disease