N-body simulations with two-orders-of-magnitude higher performance using wavelets

Noise is a problem of major concern for N-body simulations of structure formation in the early Universe, of galaxies and plasmas. Here for the first time we use wavelets to remove noise from N-body simulations of disc galaxies, and show that they become equivalent to simulations with two orders of magnitude more particles. We expect a comparable improvement in performance for cosmological and plasma simulations. Our wavelet code will be described in a following paper, and will then be available on request.Comment: Mon. Not. R. Astron. Soc., in press. The interested reader is strongly recommended to ignore the low-resolution Fig. 3 (and Fig. 4), and to download the full-resolution paper (700 kb) from http://www.oso.chalmers.se/~romeo/Paper_VI.ps.g

Parasitic pumping currents in an interacting quantum dot

We analyze the charge and spin pumping in an interacting dot within the almost adiabatic limit. By using a non-equilibrium Green's function technique within the time-dependent slave boson approximation, we analyze the pumped current in terms of the dynamical constraints in the infinite-U regime. The results show the presence of parasitic pumping currents due to the additional phases of the constraints. The behavior of the pumped current through the quantum dot is illustrated in the spin-insensitive and in the spin-sensitive case relevant for spintronics applications

Noise Estimates for Measurements of Weak Lensing from the Lyman-alpha Forest

We have proposed a method for measuring weak lensing using the Lyman-alpha forest. Here we estimate the noise expected in weak lensing maps and power spectra for different sets of observational parameters. We find that surveys of the size and quality of the ones being done today and ones planned for the future will be able to measure the lensing power spectrum at a source redshift of z~2.5 with high precision and even be able to image the distribution of foreground matter with high fidelity on degree scales. For example, we predict that Lyman-alpha forest lensing measurement from the Dark Energy Spectroscopic Instrument survey should yield the mass fluctuation amplitude with statistical errors of 1.5%. By dividing the redshift range into multiple bins some tomographic lensing information should be accessible as well. This would allow for cosmological lensing measurements at higher redshift than are accessible with galaxy shear surveys and correspondingly better constraints on the evolution of dark energy at relatively early times.Comment: 8 pages, 8 figures, submitted to MNRA

New Italian Languages

Questo saggio analizza come, in Italia, le scrittrici migranti (e postmigranti) contemporanee stiano cambiando la lingua nazionale dall'interno. Scrivendo in italiano, queste autrici aspirano ad essere accettate come parte integrante del discorso nazionale italiano – socialmente, politicamente, culturalmente, artisticamente – ed inoltre vogliono che la cultura italiana sia pronta ad accettare e comprendere le differenze presenti all'interno di una presunta omogeneità. Al rapporto istituzionale instaurato dalla legge, che le classifica come “ospiti indesiderati”, rispondono attraverso i loro testi mettendo in discussione la nozione stessa di “italianità”. Se la condizione di scrittore è una strategia per acquistare autorità, questi artisti stanno rivendicando – e stanno ottenendo – il diritto di diventare soggetti (legali) presenti a pieno titolo all’interno della cultura italiana

SmokeFree Sports Project Report

Children and young people are amongst the most vulnerable groups in society and are highly susceptible to smoking experimentation and addiction. In Liverpool, smoking prevalence is significantly higher than the UK average. Therefore early intervention strategies are required for smoking prevention and cessation. Research has found a negative association between smoking and physical activity. SmokeFree Sports aims to explore whether physical activity and sport can be used to promote the smoke free message to children and young people. SmokeFree Sports is an innovative multi-dimensional campaign that incorporates social-marketing strategies alongside the provision of sports and physical activities to: a) de-normalise smoking among youth b) empower youth to stay smoke free, and c) increase awareness of the dangers of smoking using positive messaging through the medium of sport and physical activity. This project is delivered across Liverpool and aims to reduce the prevalence of smoking and prevent the uptake of smoking in children and young people. The initiative, which is managed by Liverpool John Moores University in partnership with Liverpool PCT, employs a variety of strategies to promote and deliver the smoke free message to children and young people including a) training sports coaches and teachers to deliver the smoke free message, b) delivering SFS messages in schools and youth clubs through sport and physical activity, c) asking children to sign a pledge to be smoke free, d) support voluntary sports clubs to adopt a smoke free policy on their playing fields, e) encouraging organizations and individuals interested in health and sport to sign up to the SmokeFree Sports Charter and f) signposting children to smoking cessation services

Notable 19th century American accountants that could be considered for the Accounting Hall-of-Fame

In America, the 19th century marked the beginning of substantial economic changes (development of the vast railroad system, industrialization, and unsatiated demand for capital), providing an environment conducive to the establishment of a new profession, public accountancy. There were many accounting pioneers in the United States who helped the accounting profession develop during this transitional period. Many of the 19th century American accountants are not as well known as their 20th century counterparts, and only two accountants who worked primarily in the 19th century are currently in the Hall of Fame; Charles E. Sprague and Charles Haskins. Until recently, there was a stipulation that prevented 19th century accountants from entering the Accounting Hall of Fame; that is, a person must have contributed to the accounting field since the beginning of the 20th century

A Study of the Relationship Bettween Soil and Quantitative Terrain Factors

The objective of the study was to determine whether or not different soil areas in Hawaii could be separated by means of quantitative terrain factors. Eight great soil group areas on Oahu and six soil association areas on Kauai were selected. A sufficient number of 0.5-mile square test cells was established at random in each of the soil areas. Ten terrain factors were quantified in each of the test cells from data measured on either the topographic maps or the aerial photographs or both. The results showed that certain great soil groups on Oahu and certain soil associations on Kauai can be differentiated by their quantitative terrain factors. Average elevation, local relief, average slope, slope length, land texture ratio and drainage density were found effective in differentiating between these different groups and associations. Four terrain factors has been found effective in separating the Haplustox, Eutrorthox and Gibbsihumox areas on Oahu. These factors, in the order of decreasing effectiveness, were average slope, drainage density, slope length and local relief. The discriminant function equation developed for Tropohumult and Gibbsihumox areas, based on average elevation, average slope, slope length and drainage density, has satisfactorily segregated the two soil areas on Oahu. The results of the numerical grouping analysis of 108 test cells established in 0.5-mile grids in eastern Kauai indicated that numerical methods on the basis of several terrain factors has much to offer in reconnaissance soil surveys of large, relatively undeveloped regions where information about the soil is not available

Noise-assisted Thouless pump in elastically deformable molecular junctions

We study a Thouless pump realized with an elastically \textit{deformable quantum dot} whose center of mass follows a non-linear stochastic dynamics. The interplay of noise, non-linear effects, dissipation and interaction with an external time-dependent driving on the pumped charge is fully analyzed. The results show that the quantum pumping mechanism not only is not destroyed by the force fluctuations, but it becomes stronger when the forcing signal frequency is tuned close to the resonance of the vibrational mode. The robustness of the quantum pump with temperature is also investigated and an exponential decay of the pumped charge is found when the coupling to the vibrational mode is present. Implications of our results for nano-electromechanical systems are also discussed.Comment: 2 Appendices and figures adde