Some Winter Flowering Plants

While collecting native specimens for a herbarium during the fall of 1923, it was noticed that several species bloomed quite late, and would stand freezing and thawing time after time, without apparent damage to the flowers. A geranium which was left out of doors in a flower pot, and lived until the latter part of December, aroused our curiosity as to just how much cold weather some plants would stand

Energy gap of the bimodal two-dimensional Ising spin glass

An exact algorithm is used to compute the degeneracies of the excited states of the bimodal Ising spin glass in two dimensions. It is found that the specific heat at arbitrary low temperature is not a self-averaging quantity and has a distribution that is neither normal or lognormal. Nevertheless, it is possible to estimate the most likely value and this is found to scale as L^3 T^(-2) exp(-4J/kT), for a L*L lattice. Our analysis also explains, for the first time, why a correlation length \xi ~ exp(2J/kT) is consistent with an energy gap of 2J. Our method allows us to obtain results for up to 10^5 disorder realizations with L <= 64. Distributions of second and third excitations are also shown.Comment: 4 pages, 4 figure

Domain wall entropy of the bimodal two-dimensional Ising spin glass

We report calculations of the domain wall entropy for the bimodal two-dimensional Ising spin glass in the critical ground state. The L * L system sizes are large with L up to 256. We find that it is possible to fit the variance of the domain wall entropy to a power function of L. However, the quality of the data distributions are unsatisfactory with large L > 96. Consequently, it is not possible to reliably determine the fractal dimension of the domain walls.Comment: 4 pages, 2 figures, submitted to PR

ATOS: Integration of advanced technology software within distributed Spacecraft Mission Operations Systems

The Advanced Technology Operations System (ATOS) is a program of studies into the integration of advanced applications (including knowledge based systems (KBS)) with ground systems for the support of spacecraft mission operations

Influences of increasing temperature on Indian wheat: quantifying limits to predictability

As climate changes, temperatures will play an increasing role in determining crop yield. Both climate model error and lack of constrained physiological thresholds limit the predictability of yield. We used a perturbed-parameter climate model ensemble with two methods of bias-correction as input to a regional-scale wheat simulation model over India to examine future yields. This model configuration accounted for uncertainty in climate, planting date, optimization, temperature-induced changes in development rate and reproduction. It also accounts for lethal temperatures, which have been somewhat neglected to date. Using uncertainty decomposition, we found that fractional uncertainty due to temperature-driven processes in the crop model was on average larger than climate model uncertainty (0.56 versus 0.44), and that the crop model uncertainty is dominated by crop development. Simulations with the raw compared to the bias-corrected climate data did not agree on the impact on future wheat yield, nor its geographical distribution. However the method of bias-correction was not an important source of uncertainty. We conclude that bias-correction of climate model data and improved constraints on especially crop development are critical for robust impact predictions

Finite-Size Scaling in the Energy-Entropy Plane for the 2D +- J Ising Spin Glass

For $L \times L$ square lattices with $L \le 20$ the 2D Ising spin glass with +1 and -1 bonds is found to have a strong correlation between the energy and the entropy of its ground states. A fit to the data gives the result that each additional broken bond in the ground state of a particular sample of random bonds increases the ground state degeneracy by approximately a factor of 10/3. For $x = 0.5$ (where $x$ is the fraction of negative bonds), over this range of $L$, the characteristic entropy defined by the energy-entropy correlation scales with size as $L^{1.78(2)}$. Anomalous scaling is not found for the characteristic energy, which essentially scales as $L^2$. When $x= 0.25$, a crossover to $L^2$ scaling of the entropy is seen near $L = 12$. The results found here suggest a natural mechanism for the unusual behavior of the low temperature specific heat of this model, and illustrate the dangers of extrapolating from small $L$.Comment: 9 pages, two-column format; to appear in J. Statistical Physic

Political mobilisation by minorities in Britain: negative feedback of ‘race relations'?

This article uses a political opportunity approach to study the relationship of minority groups to the political community in Britain. The main argument is that the British race relations approach established in the 1960s had an important effect that still shapes the patterns of political contention by different minority groups today. Original data on political claims-making by minorities demonstrate that British 'racialised' cultural pluralism has structured an inequality of opportunities for the two main groups, African-Caribbeans and Indian subcontinent minorities. African-Caribbeans mobilise along racial lines, use a strongly assimilative 'black' identity, conventional action forms, and target state institutions with demands for justice that are framed within the recognised framework of race relations. Conversely, a high proportion of the Indian subcontinent minority mobilisation is by Muslim groups, a non-assimilative religious identity. These are autonomously organised, but largely make public demands for extending the principle of racial equality to their non-racial group. Within the Indian subcontinent minorities, the relative absence of mobilisation by Indian, Sikh and Hindu minorities, who have achieved much better levels of socio-economic success than Pakistani and Bangladeshi Muslims, suggests that there is also a strong socioeconomic basis for shared experiences and grievances as Muslims in Britain. This relativises the notion that Muslim mobilisation is Britain is purely an expression of the right for cultural difference per se, and sees it as a product of the paradoxes of British race relations

Mapping land-use fluxes for 2001–2020 from global models to national inventories

With the focus of climate policy shifting from pledges to implementation, there is an increasing need to track progress on climate change mitigation at country level, especially for the land-use sector. Despite new tools and models offering unprecedented monitoring opportunities, striking differences remain in estimations of anthropogenic land-use CO2 fluxes between the national greenhouse gas inventories (NGHGIs) used to assess compliance with the Paris Agreement, and the Global Carbon Budget and IPCC assessment reports, both based on global bookkeeping models (BMs).G.G. acknowledges funding from the EU’s Horizon 2020 VERIFY project (no. 776810). J.G.C. acknowledges the support of the Australian National Environmental Science Program - Climate Systems Hub. T.G. acknowledges support from the European Union’s Horizon 2020 research and innovation programme under grant agreement #101003536 (ESM2025 project), and by the Austrian Science Fund (FWF) under grant agreement P31796-N29 (ERM project). The authors thank Peter Anthoni and Almut Arneth (LPJ-GUESS model) and Sebastian Lienert (LPX model