An Empirical Study of Review Mechanisms in Environmental Regimes

This report is part of a large scale comparison of how implementation review mechanisms (IRMs) are used in international environmental agreements. Broadly, IRMs are the means by which data is exchanged and gathered, reviewed and assessed in the context of an international agreement, and by which problems of compliance and inadequate performance are managed. Here we describe the data protocol that is being used in assembling a database of review mechanisms and explain the rationale behind all the major questions in the protocol. The protocol consists of questions about the general features of agreements as well as more focussed questions concerning: how information relating to national performance and compliance is gathered and disseminated; how that information is assessed; and the means by which the parties and the agreement respond to potential problems of noncompliance and inadequate performance. The database is useful in part because it organizes information about different international environmental agreements into a comparable format and thus aids in the selection of appropriate cases and comparisons for further research. It is also useful because it can aid in the testing of hypotheses about which aspects of international agreements and review mechanisms lead agreements to be more effective. We are now using it for both purposes, in addition to extending the number of cases in the database. To date, over fifty cases have been coded using the protocol. Here we also report some observations and hypotheses derived from working with the data from those cases. These include: 1) a hypothesis that review mechanisms tend to grow as needed to fulfill demand for specific functions; 2) a hypothesis that review mechanisms might help the parties to an agreement address various forms of complexity that arise in negotiating and managing international agreements; 3) a questions as to whether and how often institutions that are formally outside a particular agreement but with competence or power in the issue-area de facto provide the review mechanisms for the agreement; 4) a question as to whether review mechanisms make their largest contribution to effectiveness when the obligations of an agreement are precise or vague; 5) a question as to whether in practice some of the functions of review mechanisms are performed by dispute resolution mechanisms, which tend to be formally created in most international agreements (but appear to be rarely used in environmental agreements)

Evidence for Shape Co-existence at medium spin in 76Rb

Four previously known rotational bands in 76Rb have been extended to moderate spins using the Gammasphere and Microball gamma ray and charged particle detector arrays and the 40Ca(40Ca,3pn) reaction at a beam energy of 165 MeV. The properties of two of the negative-parity bands can only readily be interpreted in terms of the highly successful Cranked Nilsson-Strutinsky model calculations if they have the same configuration in terms of the number of g9/2 particles, but they result from different nuclear shapes (one near-oblate and the other near-prolate). These data appear to constitute a unique example of shape co-existing structures at medium spins.Comment: Accepted for publication in Physics Letters

Geodesic distance for right invariant Sobolev metrics of fractional order on the diffeomorphism group

We study Sobolev-type metrics of fractional order $s\geq0$ on the group \Diff_c(M) of compactly supported diffeomorphisms of a manifold $M$. We show that for the important special case $M=S^1$ the geodesic distance on \Diff_c(S^1) vanishes if and only if $s\leq\frac12$. For other manifolds we obtain a partial characterization: the geodesic distance on \Diff_c(M) vanishes for $M=\R\times N, s<\frac12$ and for $M=S^1\times N, s\leq\frac12$, with $N$ being a compact Riemannian manifold. On the other hand the geodesic distance on \Diff_c(M) is positive for $\dim(M)=1, s>\frac12$ and $\dim(M)\geq2, s\geq1$. For $M=\R^n$ we discuss the geodesic equations for these metrics. For $n=1$ we obtain some well known PDEs of hydrodynamics: Burgers' equation for $s=0$, the modified Constantin-Lax-Majda equation for $s=\frac 12$ and the Camassa-Holm equation for $s=1$.Comment: 16 pages. Final versio

Determination of the String Scale in D-Brane Scenarios and Dark Matter Implications

We analyze different phenomenological aspects of D-brane constructions. First, we obtain that scenarios with the gauge group and particle content of the supersymmetric standard model lead naturally to intermediate values for the string scale, in order to reproduce the value of gauge couplings deduced from experiments. Second, the soft terms, which turn out to be generically non universal, and Yukawa couplings of these scenarios are studied in detail. Finally, using these soft terms and the string scale as the initial scale for their running, we compute the neutralino-nucleon cross section. In particular we find regions in the parameter space of D-brane scenarios with cross sections in the range of $10^{-6}$--$10^{-5}$ pb, i.e. where current dark matter experiments are sensitive. For instance, this can be obtained for $\tan\beta > 5$.Comment: Figures improved, misprints corrected, results basically unchange

Diet and feeding in the Cape Cobra, Naja nivea

It is widely reported that African cobras (genus Naja) are generalist predators, but examination of formal literature yields relatively little evidence of this for most species. Here, we review the diet of cape cobras (Naja nivea) based on examination of museum specimens, an extensive literature review, and social media reported natural history observations. We quantify dietary niche breadth and test the hypothesis that cape cobras are generalist predators. Additionally, we test the hypotheses that diet varies significantly (1) across biomes, and (2) across winter, summer and year-round rainfall regions. We gathered 101 feeding records for cape cobras and based on family-level prey frequencies calculated Levins’ measure of niche breadth as B = 6.57, which we standardised to BA = 0.29. We found no association between prey classes and biomes or rainfall region. Our data indicate that cape cobras consume a wide range of vertebrate prey from all four tetrapod classes, including a large number and diversity of snakes. Our findings suggest that cape cobras may be involved in several important ecological processes. Moreover, our study demonstrates the utility and value of collating natural history observations reported on social media platforms

Dilatonic Black Holes with Gauss-Bonnet Term

We discuss black holes in an effective theory derived from a superstring model, which includes a dilaton field, a gauge field and the Gauss-Bonnet term. Assuming U(1) or SU(2) symmetry for the gauge field, we find four types of spherically symmetric solutions, i.e., a neutral, an electrically charged, a magnetically charged and a ``colored'' black hole, and discuss their thermodynamical properties and fate via the Hawking evaporation process. For neutral and electrically charged black holes, we find critical point and a singular end point. Below the mass corresponding to the critical point, nosolution exists, while the curvature on the horizon diverges and anaked singularity appears at the singular point. A cusp structure in the mass-entropy diagram is found at the critical point and black holes on the branch between the critical and singular points become unstable. For magnetically charged and ``colored" black holes, the solution becomes singular just at the end point with a finite mass. Because the black hole temperature is always finite even at the critical point or the singular point, we may conclude that the evaporation process will not be stopped even at the critical point or the singular point, and the black hole will move to a dynamical evaporation phase or a naked singularity will appear.Comment: 31pages, 11figures, LaTex styl

High-spin transition quadrupole moments in neutron-rich Mo and Ru nuclei: Testing γ softness?

The transition quadrupole moments, Qt, of rotational bands in the neutron-rich, even-mass 102-108Mo and 108-112Ru nuclei were measured in the 8-16 ℏ spin range with the Doppler-shift attenuation method. The nuclei were populated as fission fragments from 252Cf fission. The detector setup consisted of the Gammasphere spectrometer and the HERCULES fast-plastic array. At moderate spin, the Qt moments are found to be reduced with respect to the values near the ground states. Attempts to describe the observations in mean-field-based models, specifically cranked relativistic Hartree-Bogoliubov theory, illustrate the challenge theory faces and the difficulty to infer information on γ softness and triaxiality from the data

Study of the B^0 Semileptonic Decay Spectrum at the Upsilon(4S) Resonance

We have made a first measurement of the lepton momentum spectrum in a sample of events enriched in neutral B's through a partial reconstruction of B0 --> D*- l+ nu. This spectrum, measured with 2.38 fb**-1 of data collected at the Upsilon(4S) resonance by the CLEO II detector, is compared directly to the inclusive lepton spectrum from all Upsilon(4S) events in the same data set. These two spectra are consistent with having the same shape above 1.5 GeV/c. From the two spectra and two other CLEO measurements, we obtain the B0 and B+ semileptonic branching fractions, b0 and b+, their ratio, and the production ratio f+-/f00 of B+ and B0 pairs at the Upsilon(4S). We report b+/b0=0.950 (+0.117-0.080) +- 0.091, b0 = (10.78 +- 0.60 +- 0.69)%, and b+ = (10.25 +- 0.57 +- 0.65)%. b+/b0 is equivalent to the ratio of charged to neutral B lifetimes, tau+/tau0.Comment: 14 page, postscript file also available at http://w4.lns.cornell.edu/public/CLN

Reaction rate for carbon burning in massive stars

Carbon burning is a critical phase for nucleosynthesis in massive stars. The conditions for igniting this burning stage, and the subsequent isotope composition of the resulting ashes, depend strongly on the reaction rate for C12+C12 fusion at very low energies. Results for the cross sections for this reaction are influenced by various backgrounds encountered in measurements at such energies. In this paper, we report on a new measurement of C12+C12 fusion cross sections where these backgrounds have been minimized. It is found that the astrophysical S factor exhibits a maximum around Ecm=3.5-4.0 MeV, which leads to a reduction of the previously predicted astrophysical reaction rate

Proximity effect at superconducting Sn-Bi2Se3 interface

We have investigated the conductance spectra of Sn-Bi2Se3 interface junctions down to 250 mK and in different magnetic fields. A number of conductance anomalies were observed below the superconducting transition temperature of Sn, including a small gap different from that of Sn, and a zero-bias conductance peak growing up at lower temperatures. We discussed the possible origins of the smaller gap and the zero-bias conductance peak. These phenomena support that a proximity-effect-induced chiral superconducting phase is formed at the interface between the superconducting Sn and the strong spin-orbit coupling material Bi2Se3.Comment: 7 pages, 8 figure