Rare gas analysis of size fractions from the Fayetteville meteorite

Eight size separates of grains from the Fayetteville meteorite ranging from less than 20 microns to greater than 1 millimeter are being analyzed for their rare gas elemental and isotopic composition. Measurements on five samples were performed. All five reveal a mixture of solar, planetary, cosmic ray produced and radiogenic gases. The solar component is of particular interest since it suggest that the meteorite may represent a fragment of an ancient protoplanetary regolith which was exposed to the solar wind. Solar wind elements are implanted in the outer few hundred Angstroms of exposed grains and are therefore expected to be surface correlated. At present the data do not suggest that such a correlation exists, but the final conclusion must await further analyses and data reduction

Cluster and Feature Modeling from Combinatorial Stochastic Processes

One of the focal points of the modern literature on Bayesian nonparametrics has been the problem of clustering, or partitioning, where each data point is modeled as being associated with one and only one of some collection of groups called clusters or partition blocks. Underlying these Bayesian nonparametric models are a set of interrelated stochastic processes, most notably the Dirichlet process and the Chinese restaurant process. In this paper we provide a formal development of an analogous problem, called feature modeling, for associating data points with arbitrary nonnegative integer numbers of groups, now called features or topics. We review the existing combinatorial stochastic process representations for the clustering problem and develop analogous representations for the feature modeling problem. These representations include the beta process and the Indian buffet process as well as new representations that provide insight into the connections between these processes. We thereby bring the same level of completeness to the treatment of Bayesian nonparametric feature modeling that has previously been achieved for Bayesian nonparametric clustering.Comment: Published in at http://dx.doi.org/10.1214/13-STS434 the Statistical Science (http://www.imstat.org/sts/) by the Institute of Mathematical Statistics (http://www.imstat.org

From guest worker to cultural cosmopolitan : evolving identities in Emine Sevgi Özdamar’s short story cycle Der Hof im Spiegel

The title story of Emine Sevgi Özdamar’s ‘Der Hof im Spiegel’ has received the most critical attention of any piece from the collection, leading to the neglect of the composition of the collection as a whole. Reading it as a short story cycle and examining the connections between the texts reveals that they track developments in migration and integration from before German unification into the 1990s. Through her narrator Özdamar comments on developments in social initiatives to promote integration and mutual understanding, as well as advocating direct individual contact as the basis for intercultural understanding. She also explores possibilities of identification for those with a diasporic background which look beyond social models such as multiculturalism and transcend national borders and citizenship. In particular, Özdamar explores the potential of an adaptive cultural cosmopolitanism for establishing new lattices of identification as the basis for a re-orientated subjectivity in migration

The sensitivity of Cook Glacier, East Antarctica, to changes in ice-shelf extent and grounding-line position

The Wilkes Subglacial Basin in East Antarctica contains ice equivalent to 3–4 m of global mean sea level rise and is primarily drained by Cook Glacier. Of concern is that recent observations (since the 1970s) show an acceleration in ice speed over the grounding line of both the Eastern and Western portions of Cook Glacier. Here, we use a numerical ice-flow model (Úa) to simulate the instantaneous effects of observed changes at the terminus of Cook Glacier in order to understand the link between these changes and recently observed ice acceleration. Simulations suggest that the acceleration of Cook West was caused by a retreat in calving-front position in the 1970s, potentially enhanced by grounding-line retreat, while acceleration of Cook East was likely caused by ice-shelf thinning and grounding-line retreat in the mid-1990s. Moreover, we show that the instantaneous ice discharge at Cook East would increase by up to 85% if the whole ice shelf is removed and it ungrounds from a pinning point; and that the discharge at Cook West could increase by ~300% if its grounding line retreated by 10 km

Controlling Cyberwarfare: International Laws of Armed Conflict and Human Rights in the Cyber Realm

Cyberwarfare, military activities in cyberspace conducted by a state against another state and intended to disrupt or destroy computing or communica­tion systems or data, is a recent addition to the warfaring arsenal. The in­ternational laws of armed conflict set out an obligation for states at war to protect civilians from the effects of the conflict. As societies continue to ex­pand their activities in the cyber realm, the risk of cyberwarfare negatively affecting the civilian population increases. The international community, recognizing this risk, is engaged in a political dance trying to identify the constraints that international law already places on cyberwarfare while stak­ing out ground to preserve its effectiveness as a means of influencing other states’ policies. This dissertation project addresses some of the problems posed by the use of computing and network technology as weapons and tar­gets in the context of international armed conflict. It brings together mate­rial drawn from computing technology, military handbooks, policy research, international standards for records preservation, non­government organiza­tions, international humanitarian law, international human rights law, the international laws of armed conflict, and real­-world examples to reveal the complexity and nuances of using operations in cyberspace to produce ef­fects in meatspace, the physical world of humans, buildings, equipment, and artefacts. First, I argue that since there is no significant difference between using cyber means of war and conventional means of war, it is appropriate to treat developments in cyberwarfare under the existing international laws of armed conflict. Then I introduce the Tallinn Manual, a handbook on the international law applicable to cyber operations, and the events that led to its development. I examine how well the Tallinn Manual documents the pro­tections, prohibitions, and permissions extended under the laws of armed conflict, concluding that it is a faithful interpretation of international law. The application of international law to warfare is always messy and im­precise. Its application to cyberwarfare is no different. This does not mean that the constraints of international law are without value or purpose. On the assumption that no state wants to start an international armed conflict, but is prepared to respond to uses of force, I apply some of the principles expressed in the Tallinn Manual to establish qualitative assessments of the severity of initial aggressive cyberoperations against a state, classifying them as moderate or flagrant attacks depending on the harm they produced. This helps the target state determine whether there is just cause for a use of force, either cyber or conventional, in response, and the constraints that apply to any response that may be permissible under international law. International law also affords protections for human rights, both in peace­ time and during times of conflict. I argue that cyberwarfare exposes more civilian objects, including objects of cultural significance and records needed to safeguard human rights, to harm through both conventional and cyber at­tacks. If human rights are to be protected, the records (digital or otherwise) that serve as evidence in support of rights claims must be protected as well. I conclude that international law already sets out the obligation for these protections, but the interpretation of international law must make explicit the expectation that all parties in an armed conflict will make efforts to iden­tify and preserve these objects for the well­being of persons in a post­conflict society. Finally, I demonstrate the breadth and applicability of further work in this area. I point out some other problems that branch off from this partic­ular project: the separation of information content from its representation in different media, human rights in the cyber domain, the use of comput­ing and communication technology to produce social or economic disrup­tion, the status of privately­-owned satellites under the multiple international treaties and conventions during times of armed conflict, and the assignment of peacetime responsibility for safeguarding data essential for the protection and provision of human rights

Revisiting the universal texture zero of flavour: a Markov chain Monte Carlo analysis

We revisit the phenomenological predictions of the Universal Texture Zero (UTZ) model of flavour originally presented in [1], and update them in light of both improved experimental constraints and numerical analysis techniques. In particular, we have developed an in-house Markov Chain Monte Carlo (MCMC) algorithm to exhaustively explore the UTZ’s viable parameter space, considering both leading- and next-to-leading contributions in the model’s effective operator product expansion. We also extract – for the first time – reliable UTZ predictions for the (poorly constrained) leptonic CP-violating phases, and ratio observables that characterize neutrino masses probed by (e.g.) oscillation, β-decay, and cosmological processes. We therefore dramatically improve on the proof-in-principle phenomenological analysis originally presented in [1], and ultimately show that the UTZ remains a minimal, viable, and appealing theory of flavour. Our results also further demonstrate the potential of robustly examining multi-parameter flavour models with MCMC routines