Revised proposal for encoding the Lanna script in the BMP of the UCS

This is a proposal to encode the Lanna script in the international character encoding standard Unicode. The name of the script was changed to "Tai Tham" by consensus of users in different countries. Tai Tham was published in Unicode Standard version 5.2 in October 2009. Tai Tham is used to write Northern Thai, Lue, and Khün, which are spoken in Northern Thailand, Myanmar, China and surrounding areas. It is also used for Lao Tham (Old Lao). The script is known by various names: Old Xishuangbanna Dai or Old Tai Lue in China, Khün in Myanmar, and Tua Mueang, Lanna, or Yuan in Thailand. Several changes have been made to the script since the proposal was written, so users should check the latest code charts, accessible from , and section 16.7 in the Unicode Standard

The organisation and functions of local Ca²⁺ signals

Calcium (Ca2+) is a ubiquitous intracellular messenger, controlling a diverse range of cellular processes, such as gene transcription, muscle contraction and cell proliferation. The ability of a simple ion such as Ca2+ to play a pivotal role in cell biology results from the facility that cells have to shape Ca2+ signals in space, time and amplitude. To generate and interpret the variety of observed Ca2+ signals, different cell types employ components selected from a Ca2+ signalling 'toolkit', which comprises an array of homeostatic and sensory mechanisms. By mixing and matching components from the toolkit, cells can obtain Ca2+ signals that suit their physiology. Recent studies have demonstrated the importance of local Ca2+ signals in defining the specificity of the interaction of Ca2+ with its targets. Furthermore, local Ca2+ signals are the triggers and building blocks for larger global signals that propagate throughout cells

log(M_Pl/m_3/2)

Flux compactifications of string theory seem to require the presence of a fine-tuned constant in the superpotential. We discuss a scheme where this constant is replaced by a dynamical quantity which we argue to be a `continuous Chern--Simons term'. In such a scheme, the gaugino condensate generates the hierarchically small scale of supersymmetry breakdown rather than adjusting its size to a constant. A crucial ingredient is the appearance of the hierarchically small quantity exp(-) which corresponds to the scale of gaugino condensation. Under rather general circumstances, this leads to a scenario of moduli stabilization, which is endowed with a hierarchy between the mass of the lightest modulus, the gravitino mass and the scale of the soft terms, m_modulus ~ m_3/2 ~ ^2 m_soft. The `little hierarchy' is given by the logarithm of the ratio of the Planck scale and the gravitino mass, ~ log(M_Pl/m_3/2) ~ 4pi^2. This exhibits a new mediation scheme of supersymmetry breakdown, called mirage mediation. We highlight the special properties of the scheme, and their consequences for phenomenology and cosmology.Comment: Based on talks given at PLANCK05, Trieste, Italy and PASCOS05, Gyeongju, Kore

Implications of a temperature-dependent magnetic anisotropy for superparamagnetic switching

The macroscopic magnetic moment of a superparamagnetic system has to overcome an energy barrier in order to switch its direction. This barrier is formed by magnetic anisotropies in the material and may be surmounted typically after 10^9 to 10^12 attempts per second by thermal fluctuations. In a first step, the associated switching rate may be described by a Neel-Brown-Arrhenius law, in which the energy barrier is assumed as constant or a given temperature. Yet, magnetic anisotropies in general depend on temperature themselves which is known to modify the Neel-Brown-Arrhenius law. We illustrate quantitatively the implications of a temperature-dependent anisotropy on the switching rate and in particular for the interpretation of the prefactor as an attempt frequency. In particular, we show that realistic numbers for the attempt frequency are obtained when the temperature dependence of the anisotropy is taken into account.Comment: 15 pages, 5 figure

Carbon emissions pinch analysis (CEPA) for emissions reduction in the New Zealand electricity sector

Carbon Emissions Pinch Analysis (CEPA) is a recent extension of traditional thermal and mass pinch analysis to the area of emissions targeting and planning on a macroscale (i.e. economy wide). This paper presents a carbon pinch analysis of the New Zealand electricity industry and illustrates some of the issues with realising meaningful emissions reductions. The current large proportion of renewable generation sources (~67% in 2007) complicates wholesale emissions reductions. The biggest growth in renewable generation is expected to come from geothermal energy followed by wind and hydro. A four fold increase in geothermal generation capacity is needed in addition to large amounts of new wind generation to reduce emissions to around 1990 levels and also meet projected demand. The expected expansion of geothermal generation in New Zealand raises issues of GHG emissions from the geothermal fields. The emissions factors between fields can vary by almost two orders of magnitude making predictions of total emissions highly site specific

Methane release on Early Mars by atmospheric collapse and atmospheric reinflation

A candidate explanation for Early Mars rivers is atmospheric warming due to surface release of H$_2$ or CH$_4$ gas. However, it remains unknown how much gas could be released in a single event. We model the CH$_4$ release by one mechanism for rapid release of CH$_4$ from clathrate. By modeling how CH$_4$-clathrate release is affected by changes in Mars' obliquity and atmospheric composition, we find that a large fraction of total outgassing from CH$_4$ clathrate occurs following Mars' first prolonged atmospheric collapse. This atmosphere-collapse-initiated CH$_4$-release mechanism has three stages. (1) Rapid collapse of Early Mars' carbon dioxide atmosphere initiates a slower shift of water ice from high ground to the poles. (2) Upon subsequent CO$_2$-atmosphere re-inflation and CO$_2$-greenhouse warming, low-latitude clathrate decomposes and releases methane gas. (3) Methane can then perturb atmospheric chemistry and surface temperature, until photochemical processes destroy the methane. Within our model, we find that under some circumstances a Titan-like haze layer would be expected to form, consistent with transient deposition of abundant complex abiotic organic matter on the Early Mars surface. We also find that this CH$_4$-release mechanism can warm Early Mars, but special circumstances are required in order to uncork 10$^{17}$ kg of CH$_4$, the minimum needed for strong warming. Specifically, strong warming only occurs when the fraction of the hydrate stability zone that is initially occupied by clathrate exceeds 10%, and when Mars' first prolonged atmospheric collapse occurs for atmospheric pressure > 1 bar.Comment: Accepted by Planetary and Space Scienc