Reheating temperature from the CMB

In the recent paper by Mielczarek \emph{et al.} (JCAP {\bf 1007} (2010) 004) an idea of the method which can be used to put some constraint for the reheating phase was proposed. Another method of constraining the reheating temperature has been recently studied by Martin and Ringeval (Phys.\ Rev.\ D {\bf 82} (2010) 023511). Both methods are based on observations of the cosmic microwave background (CMB) radiation. In this paper, we develop the idea introduced in this first article to put constraint on the reheating after the slow-roll inflation. We restrict our considerations to the case of a massive inflaton field. The method can be, however, easily extended to the different inflationary scenarios. As a main result, we derive an expression on the reheating temperature $T_{\text{RH}}$. Surprisingly, the obtained equation is independent on the unknown number of relativistic degrees of freedom $g_*$ produced during the reheating. Based on this equation and the WMAP 7 observations, we find $T_{\text{RH}}=3.5\cdot 10^6$ GeV, which is consistent with the current constraints. The relative uncertainty of the result is, however, very high and equal to $\sigma(T_{\text{RH}})/T_{\text{RH}} \approx 53$. As we show, this uncertainty will be significantly reduced with future CMB experiments.Comment: 6 pages, 3 figures. Matches version published in Phys. Rev.

Ground-state phase diagrams of the generalized Falicov-Kimball model with Hund coupling

Charge and spin orderings are studied on the simplest 1D and the 2D square lattice within the generalized Falicov-Kimball model with Hund coupling between localized and itinerant electrons. Using the restricted phase diagrams method (RPDM) a number of simple rules of formation of various sorts of ground state phases have been detected. In particular, relationships between density of current carriers (electrons or holes) and type of charge and magnetic arrangement has been determined. In 2D in the mixed valence regime only axial stripes (vertical or horizontal) have been found for intermediate values of the coupling constants. They are composed of ferromagnetic or antiferromagnetic chains interchanged with non-magnetic ones. For band fillings close to the half filling stripe phases oriented along one of the main diagonal direction are formed. The results suggest a possibility of tuning modulations of charge and magnetic superstructures with a change of doping.Comment: 10 pages, 6 figures; Fig. 2 slightly modified and the text adjusted accordingly, references adde

What do Bayesian methods offer population forecasters?

The Bayesian approach has a number of attractive properties for probabilistic forecasting. In this paper, we apply Bayesian time series models to obtain future population estimates with uncertainty for England and Wales. To account for heterogeneity found in the historical data, we add parameters to represent the stochastic volatility in the error terms. Uncertainty in model choice is incorporated through Bayesian model averaging techniques. The resulting predictive distributions from Bayesian forecasting models have two main advantages over those obtained using traditional stochastic models. Firstly, data and uncertainties in the parameters and model choice are explicitly included using probability distributions. As a result, more realistic probabilistic population forecasts can be obtained. Second, Bayesian models formally allow the incorporation of expert opinion, including uncertainty, into the forecast. Our results are discussed in relation to classical time series methods and existing cohort component projections. This paper demonstrates the flexibility of the Bayesian approach to simple population forecasting and provides insights into further developments of more complicated population models that include, for example, components of demographic change

Forecasting environmental migration to the United Kingdom, 2010 - 2060: an exploration using Bayesian models

Over the next fifty years the potential impact on human livelihoods of environmental change could be considerable. One possible response may be increased levels of human mobility. This paper offers a first quantification of the levels of environmental migration to the United Kingdom that might be expected. The authors apply Bijak and Wi?niowski’s (2010) methodology for forecasting migration using Bayesian models. They seek to advance the conceptual understanding of forecasting in three ways. First, the paper is believed to be the first time that the Bayesian modelling approach has been attempted in relation to environmental mobility. Second, the paper examines the plausibility of Bayesian modelling of UK immigration by cross-checking expert responses to a Delphi survey with the expectations about environmental mobility evident in the recent research literature. Third, the values and assumptions of the expert evidence provided in the Delphi survey are interrogated to illustrate the limited set of conditions under which the forecasts of environmental mobility, as set out in this paper, are likely to hold

The Limits of Sea Power

Sea powers have many handicaps that often are forgotten, resulting in a dangerous overestimation of their safety, influence, and staying power in a competitive world. A more clear-eyed assessment of sea power—one less enamored of the grandeur associated with naval might—reveals that often their hopes were unwarranted and ended up having tragic results

Analiza haplotipova genski polimorfnog hormona rasta američke vidrice (Neovison vison) pomaže objasniti razloge za njihovu vezanu neravnotežu i razlikovanje po predcima.

Haplotypes of the American mink (Neovison vison) growth hormone gene, phased from diploid multilocus genotypes of 389 individuals, were analysed. Forty-four different haplotypes, for 14 detected polymorphic loci, were identified. Significant gametic disequilibrium occurs in the case of four variable sites, with a correlation coefficient ranging from 50% to 94%. Four haplotype blocks were defined. The results of the D-statistics, conducted for the studied population, suggest that the observed linkage disequilibrium was caused by limited migration and genetic drift. Moreover, the described LD indicates a relatively low frequency of recombination events between variable loci of the American mink growth hormone gene. The developed cladogram reveals the existence of two distinctly different and internally consistent clades, which may indicate the existence of two main patterns of ancestral haplotypes, from which all the others derived. Moreover, the internal structure of the cladogram reveals their clear hierarchical arrangement, which allowed to draw conclusions regarding the origin-relationships of the identified haplotypes.Kod 389 američkih vidrica (Neovison vison) analizirani su haplotipovi gena za hormone rasta. Od diploidnih multilokusnih genotipova, među kojima je utvrđeno 14 polimorfnih lokusa, identificirana su 44 različita haplotipa. Signifikantna neravnoteža gameta javlja se u slučaju 4 varijabilna mjesta, s koeficijentom korelacije u rasponu od 50% do 94%. Definirana su 4 haplotip bloka. Rezultati D-statistike za istraženu populaciju upućuju da su opažene vezane neravnoteže uzrokovane ograničenom migracijom i genskim pomakom. Osim toga, opisana vezana neravnoteža pokazuje relativno nisku učestalost rekombinacija između varijabilnih genskih lokusa za hormon rasta američke vidrice. Konstruirani kladogram otkriva postojanje dviju potpuno različitih i unutar sebe konzistentnih kladi, što može ukazivati na dva glavna obrasca za haplotipove predaka, od kojih su izvedeni svi drugi haplotipovi. Također, unutarnja građa kladograma otkriva njihov jasan hijerarhijski raspored, što omogućuje zaključke o podrijetlu odnosa između utvrđenih haplotipova