A Nuclear-Armed Iran: Possible Security and Diplomatic Implications

Analyzes how Iran's neighbors might react to a nuclear Iran: self-help in enhancing their own defenses; bandwagoning by accommodating Iran's preferences; and balancing by moving closer to the United States or forming a collective security arrangement

North Korea and the Non-proliferation Regime

In this review of the implications of North Korea’s behaviour during 2009 on the Non-proliferation Regime, it is stressed that if North Korea cannot be deterred from its nuclear ambitions this will deliver a serious blow to the international non-proliferation regime. It will also damage the likelihood of a successful outcome at next year’s NPT Review Conference. The behaviour of North Korea so far, and especially during 2009, can be summarised as follows: failed satellite test in April, nuclear test in May, missile tests in July and additional tests of short-range missiles in October. This seems to imply that North Korea has now made its strategic choice between conciliation and hostility and that Pyongyang believes that its future security could be better preserved by maintaining a robust nuclear weapons programme. The implications of a nuclear North Korea range from diverse strategic concerns to serious humanitarian issues, while the US is faced with a number of different options, including engagement, deterrence, military pre-emption and regime change. However, all of these options have serious limitations and none promises to achieve the goal of a non-nuclear North Korea anytime soon

Corea del Norte y el nuevo paradigma de seguridad

Los últimos ensayos nucleares de Corea del Norte han provocado una nueva crisis en la península de Corea. La última detonación nuclear de Corea del Norte, sus ensayos con misiles balísticos y su provocadora retórica han causado una nueva crisis en la península de Corea. En vez de intentar obligar a este país a volver a la mesa de negociaciones a seis bandas para continuar con unas conversaciones que no llevan a ninguna parte, sería mucho mejor reconocer que el entorno de seguridad del noreste asiático ha cambiado radicalmente. Se precisa un nuevo paradigma de seguridad que haga hincapié en la disuasión y la contención y la importancia de las alianzas de EEUU

Extracellular calcium reduction strongly increases the lytic capacity of pneumolysin from streptococcus pneumoniae in brain tissue

Background. Streptococcus pneumoniae causes serious diseases such as pneumonia and meningitis. Its major pathogenic factor is the cholesterol-dependent cytolysin pneumolysin, which produces lytic pores at high concentrations. At low concentrations, it has other effects, including induction of apoptosis. Many cellular effects of pneumolysin appear to be calcium dependent. Methods. Live imaging of primary mouse astroglia exposed to sublytic amounts of pneumolysin at various concentrations of extracellular calcium was used to measure changes in cellular permeability (as judged by lactate dehydrogenase release and propidium iodide chromatin staining). Individual pore properties were analyzed by conductance across artificial lipid bilayer. Tissue toxicity was studied in continuously oxygenated acute brain slices. Results. The reduction of extracellular calcium increased the lytic capacity of the toxin due to increased membrane binding. Reduction of calcium did not influence the conductance properties of individual toxin pores. In acute cortical brain slices, the reduction of extracellular calcium from 2 to 1 mM conferred lytic activity to pathophysiologically relevant nonlytic concentrations of pneumolysin. Conclusions. Reduction of extracellular calcium strongly enhanced the lytic capacity of pneumolysin due to increased membrane binding. Thus, extracellular calcium concentration should be considered as a factor of primary importance for the course of pneumococcal meningitis

Effect of oxidations on phosphorus-diffused crystalline-silicon substrates

Phosphorus diffusions are used in the fabrication process for nearly all crystalline-silicon (c-Si) photovoltaic solar cells to form the emitter of the solar cell. These phosphorous diffusions are also well known to have beneficial gettering benefits, i.e., deleterious metallic impurities are gettered from the bulk of the c-Si substrate into the phosphorous doped layer. In this study, we examined the effect of oxidations performed after the phosphorus diffusion. We were particularly interested in using the oxidation to passivate the surface of the phosphorus diffusion. Post-diffusion oxidations or moderate temperature steps in oxidizing ambients are also commonly found in commercial fabrication sequences of c-Si solar cells. we found that the bulk lifetime was degraded in Czochralski (Cz) silicon due to the post-diffusion oxidation unless there was a gettering agent present during the oxidation. Possible explanations for these results are presented at the end of the paper

Mirror Self Recognition and Self-Identification

That great apes are the only primates to recognise their reflections is often taken to show that they are self-aware – however, there has been much recent debate about whether the self-awareness in question is psychological or bodily self-awareness. This paper argues that whilst self-recognition does not require psychological self-awareness, to claim that it requires only bodily self-awareness would leave something out. That is that self-recognition requires ‘objective self-awareness’ – the capacity for first person thoughts like ‘that’s me’, which involve self-identification and so are vulnerable to error through misidentification. This objective self-awareness is distinct from bodily or psychological self-awareness, requires cognitive sophistication and provides the beginnings of a more conceptual self-representation which might play a role in planning, mental time travel and theory of mind.This work was supported by a research studentship from Peterhouse, University of Cambridge

Numerical modelling of the microwave heating behaviour of lunar regolith

The field of In Situ Resource Utilisation (ISRU) is expanding rapidly with a particular focus on developing ISRU technologies and applications to support a longer-term surface exploration of the Moon. In this respect, microwave sintering is proposed to be one of the potential fabrication methods for developing a 3D printing technique for construction processes on the Moon. Thus, understanding the behaviour of lunar regolith, available at different locations on the Moon (e.g. mare versus highlands regions), under microwave heating is crucial for developing an optimal method for microwave sintering. As the availability of real lunar regolith on Earth is highly limited, developing an appropriate numerical model of microwave heating behaviour of lunar regolith is urgently required. In this paper, three representative lunar regolith samples (selected from the database of Apollo sample collections) with pre-defined material properties have been simulated under seven input powers and three specimen sizes. This paper discusses the outcomes of these simulations and the potential contribution of the model for developing a desired 3D printing technique utilising microwave sintering of lunar regolith