Oil and international cooperation

The more that states depend on oil exports, the less cooperative they become: they grow less likely to join intergovernmental organizations, to accept the compulsory jurisdiction of international judicial bodies, and to agree to binding arbitration for investment disputes. This pattern is robust to the use of country and year fixed effects, to alternative measures of the key variables, and to the exclusion of all countries in the Middle East. To explain this pattern, we consider the economic incentives that foster participation in international institutions: the desire to attract foreign investment and to gain access to foreign markets. Oil-exporting states, we argue, find it relatively easy to achieve these aims without making costly commitments to international institutions. In other words, natural resource wealth liberates states from the economic pressures that would otherwise drive them toward cooperation

Electroweak Breaking in Supersymmetric Models

We discuss the mechanism for electroweak symmetry breaking in supersymmetric versions of the standard model. After briefly reviewing the possible sources of supersymmetry breaking, we show how the required pattern of symmetry breaking can automatically result from the structure of quantum corrections in the theory. We demonstrate that this radiative breaking mechanism works well for a heavy top quark and can be combined in unified versions of the theory with excellent predictions for the running couplings of the model. (To be published in ``Perspectives in Higgs Physics'', G. Kane editor.)Comment: 47 page

Time-dependent Ginzburg-Landau model for light-induced superconductivity in the cuprate LESCO

Cavalleri and coworkers have discovered evidence of light-induced superconductivity and related phenomena in several different materials. Here we suggest that some features may be naturally interpreted using a time-dependent Ginzburg-Landau model. In particular, we focus on the lifetime of the transient state in La$_{1.675}$Eu$_{0.2}$Sr$_{0.125}$CuO$_4$ (LESCO$_{1/8}$), which is remarkably long below about 25 K, but exhibits different behavior at higher temperature.Comment: 5 pages, accepted by European Journal of Physics: Special Topic

Intra- and Intermolecular C−H Activation by Bis(phenolate)pyridineiridium(III) Complexes

A bis(phenolate)pyridine pincer ligand (henceforth abbreviated as ONO) has been employed to support a variety of iridium complexes in oxidation states I, III, and IV. Complexes (ONO)IrL_2Me (L = PPh_3, PEt_3) react with I_2 to cleave the Ir–C bond and liberate MeI, apparently via a mechanism beginning with electron transfer to generate an intermediate Ir(IV) complex, which can be isolated and characterized for the case L = PEt_3. The PPh_3 complex is transformed in benzene at 65 °C to the corresponding phenyl complex, with loss of methane, and subsequently to a species resulting from metalation of a PPh_3 ligand. Labeling and kinetics studies indicate that PPh_3 is the initial site of C–H activation, even though the first observed product is that resulting from intermolecular benzene activation. C–H activation of acetonitrile has also been observed

Charge Distribution Near Oxygen Vacancies in Reduced Ceria

Understanding the electronic charge distribution around oxygen vacancies in transition metal and rare earth oxides is a scientific challenge of considerable technological importance. We show how significant information about the charge distribution around vacancies in cerium oxide can be gained from a study of high resolution crystal structures of higher order oxides which exhibit ordering of oxygen vacancies. Specifically, we consider the implications of a bond valence sum analysis of Ce$_{7}$O$_{12}$ and Ce$_{11}$O$_{20}$. To illuminate our analysis we show alternative representations of the crystal structures in terms of orderly arrays of co-ordination defects and in terms of flourite-type modules. We found that in Ce$_{7}$O$_{12}$, the excess charge resulting from removal of an oxygen atom delocalizes among all three triclinic Ce sites closest to the O vacancy. In Ce$_{11}$O$_{20}$, the charge localizes on the next nearest neighbour Ce atoms. Our main result is that the charge prefers to distribute itself so that it is farthest away from the O vacancies. This contradicts \emph{the standard picture of charge localisation} which assumes that each of the two excess electrons localises on one of the cerium ions nearest to the vacancy. This standard picture is assumed in most calculations based on density functional theory (DFT). Based on the known crystal structure of Pr$_{6}$O$_{11}$, we also predict that the charge in Ce$_{6}$O$_{11}$ will be found in the second coordination shell of the O vacancy. Although this review focuses on bulk cerium oxides our approach to characterising electronic properties of oxygen vacancies and the physical insights gained should also be relevant to surface defects and to other rare earth and transition metal oxides.Comment: 20 pages, 23 figures. The replacement file has a new format for the figures are the document layout but no change in content. v3 has the following main changes: 1. The abstract and introduction were extensively revised. 2. Sec. IV was removed. 3. The Conclusion was rewritte

Exploring the challenges of implementing e-health: a protocol for an update of a systematic review of reviews.

There is great potential for e-health to deliver cost-effective, quality healthcare and spending on e-health systems by governments and healthcare systems is increasing worldwide. However, the literature often describes problematic and unsuccessful attempts to implement these new technologies into routine clinical practice. To understand and address the challenges of implementing e-health, a systematic review was conducted in 2009, which identified several conceptual barriers and facilitators to implementation. As technology is rapidly changing and new e-health solutions are constantly evolving to meet the needs of current practice, an update of this review is deemed necessary to understand current challenges to the implementation of e-health. This research aims to identify, summarise and synthesise currently available evidence, by undertaking a systematic review of reviews to explore the barriers and facilitators to implementing e-health across a range of healthcare settings

Ruin Probabilities and Overshoots for General Levy Insurance Risk Processes

We formulate the insurance risk process in a general Levy process setting, and give general theorems for the ruin probability and the asymptotic distribution of the overshoot of the process above a high level, when the process drifts to -\infty a.s. and the positive tail of the Levy measure, or of the ladder height measure, is subexponential or, more generally, convolution equivalent. Results of Asmussen and Kluppelberg [Stochastic Process. Appl. 64 (1996) 103-125] and Bertoin and Doney [Adv. in Appl. Probab. 28 (1996) 207-226] for ruin probabilities and the overshoot in random walk and compound Poisson models are shown to have analogues in the general setup. The identities we derive open the way to further investigation of general renewal-type properties of Levy processes.Comment: Published at http://dx.doi.org/10.1214/105051604000000927 in the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org