Quantum simulation of the Anderson Hamiltonian with an array of coupled nanoresonators: delocalization and thermalization effects

The possibility of using nanoelectromechanical systems as a simulation tool for quantum many-body effects is explored. It is demonstrated that an array of electrostatically coupled nanoresonators can effectively simulate the Bose-Hubbard model without interactions, corresponding in the single-phonon regime to the Anderson tight-binding model. Employing a density matrix formalism for the system coupled to a bosonic thermal bath, we study the interplay between disorder and thermalization, focusing on the delocalization process. It is found that the phonon population remains localized for a long time at low enough temperatures; with increasing temperatures the localization is rapidly lost due to thermal pumping of excitations into the array, producing in the equilibrium a fully thermalized system. Finally, we consider a possible experimental design to measure the phonon population in the array by means of a superconducting transmon qubit coupled to individual nanoresonators. We also consider the possibility of using the proposed quantum simulator for realizing continuous-time quantum walks.Comment: Replaced with new improved version. To appear in EPJ Q

h3 gourmet: not so fast food

The h3 case study focuses on the development and offer of a new chain of hamburger restaurants that began in Portugal and is spreading to other countries like Spain, Brazil and Poland. The general idea of the business venture is to grow quickly and occupy an unconventional place in the fast food burger business: a food chain with a gourmet touch, taking a high profile approach with natural ingredients, customization and quality service, where hamburgers are served on heated plates with cutlery and may be accompanied by a glass of wine, homemade lemonade or iced tea. The client can finish the meal with ice cream or chocolate coulant desserts with quality ingredients. H3 now has more than 40 restaurants; it is preparing to conquer the world and challenge the big players both in malls and street restaurants. Competitive advantages and critical success factors will play a vital role in this case

O programa nacional de fortalecimento da agricultura familiar no Brasil: uma análise sobre a distribuição regional e setorial dos recursos.

No Brasil, as políticas públicas para o espaço rural sempre tenderam a priorizar a agricultura patronal, em detrimento dos agricultores familiares. Todavia, os estudos realizados pelos órgãos FAO - INCRA deram subsídio para a criação do Programa Nacional de Fortalecimento da Agricultura Familiar (PRONAF), resultando em um novo direcionamento dos investimentos públicos, os quais passaram a contemplar o segmento dos agricultores familiares. Entende-se o PRONAF como uma política não-compensatória, que, apesar de seus problemas, tem contribuído de fato para mudanças e melhorias no espaço agrário brasileiro. Desde sua criação no final da década de 1990, o PRONAF passou por várias mudanças em sua estrutura administrativa e operacional, a fim de alcançar seus objetivos e adequar-se face a complexa realidade social agrária brasileira. Sendo assim, o presente estudo visa discutir as ações do Estado por meio desse Programa, a partir de suas linhas de atuação, bem como analisar a distribuição de suas concessões de crédito regional e setorialmente. Assim, os procedimentos metodológicos utilizados para a realização deste trabalho compreendem pesquisa bibliográfica e documental, além de pesquisa em fontes secundárias, no intuito de obter dados e informações relevantes para a análise das relações sociais estabelecidas em meio a esse processo de concretização e espacialização desse Programa. Dentre as implicações do PRONAF pode-se notar em âmbito nacional, uma diminuição da disparidade regional brasileira, bem como a preocupação que o Programa tem demonstrado com os aspectos socioculturais locais e regionais, como forma de garantir que seus investimentos perpassem a dimensão econômica, mas valorize outras dimensões, a exemplo dos elementos culturais

Molecular dynamics study of accelerated ion-induced shock waves in biological media

We present a molecular dynamics study of the effects of carbon- and iron-ion induced shock waves in DNA duplexes in liquid water. We use the CHARMM force field implemented within the MBN Explorer simulation package to optimize and equilibrate DNA duplexes in liquid water boxes of different sizes and shapes. The translational and vibrational degrees of freedom of water molecules are excited according to the energy deposited by the ions and the subsequent shock waves in liquid water are simulated. The pressure waves generated are studied and compared with an analytical hydrodynamics model which serves as a benchmark for evaluating the suitability of the simulation boxes. The energy deposition in the DNA backbone bonds is also monitored as an estimation of biological damage, something which is not possible with the analytical model

Données sur le comportement alimentaire chez Aphaenogaster Senilis Mayr 1853 (Hymenoptera Formicidae)

Es descriu la dieta í la conducta de Aphaenogaster senilis en relació amb la recerca, captura, localització i transport de l'aliment. A. senilis és omnívora, però amb preferència per les restes animals. La localització de l'aliment es fa de manera individual. El transport és individual sí la presa és transportable i única. Si és múltiple í transportable, algunes obreres de l'interior del aiu poden esdevenir transportadores. Es descriu el reclutament, de grup sense líder, i el transport col·lectiu per a preses no transportables i el "tool using" per a dissolucions ensucrades. Es fan algunes consideracions sobre variabilitat individual.The diet and food behaviour of A. Senilis are described. The diet is omnivorous, but animal food is prefered. Ants always search for food individually, and carry them individually when food is transportable and unique. If it is multiple and transportable some ants in the nest can be activated and be carriers too. Group recruitment without der to food occurs when the prey is large. Sugared liquid food is exploi ted by tool using. Variability in feeding behaviour is considered

Identifying (subsurface) anthropogenic heat sources that influence temperature in the drinking water distribution system

The water temperature in the drinking water distribution system and at the customers’ taps approaches the surrounding soil temperature at ca. 1 meter depth. Water temperature is an important determinant of water quality, since it influences physical, chemical and biological processes, such as absorption of chemicals, microbial growth and chlorine decay. In the Netherlands drinking water is distributed without additional residual disinfectant and the temperature of drinking water at the customers’ tap is not allowed to exceed 25 ºC. Routine water quality samples at the tap in urban areas have shown locations with relatively high soil temperatures compared to the expected modelled soil temperatures, which indicate so called ‘underground hot-spots’. In the last decades, the urban sub-surface is getting more occupied with various types of sub-surface infrastructures and some of these can be heat sources. A few recent studies tackle the anthropogenic sources and their influence on the underground, at coarse spatial scales. Little is known about the urban shallow underground heat profile on small spatial scales, of the order of 10 m × 10 m. Our research focuses on developing a method to identify and to localise potential underground hot-spots at −1.0 m at a small spatial scale. In this article we describe a method to find anthropogenic heat sources that influence temperature in the drinking water distribution system through a combination of mapping urban anthropogenic heat sources, modelling the soil temperature and extensive measurements in Rotterdam

Cidade emoção: o ver e o viver os espaços públicos por um grupo de jovens a partir da comunidade Carobinha no Rio de Janeiro

Este trabalho entende a cidade através do olhar de um grupo de jovens que habita um lugar sujeito às condições de pobreza. O que nos move é conjecturar como, a partir das emoções, tais jovens são capazes de construir em processos interacionais no e com o espaço urbano, a percepção de cidade ao localizarem nesta, suas identidades. Para a caracterização desta cidade, que convencionamos chamar “cidade emoção”, coletamos as representações que os jovens expressam em desenhos e falas sobre o espaço urbano, uma vez que são imagens gravadas no imaginário coletivo. O objetivo de nossa pesquisa foi entender o espaço vivenciado do Rio de Janeiro, através dos processos perceptivos de jovens que trazem à tona a complexidade urbana à medida que revelam a identidade do território cotidiano de suas experiências. Por conseguinte, essa relação interacional dos jovens, converte-se em uma das peças fundamentais e tecedoras da construção do indivíduo, que analisamos com base na ideia de Vygotski (1998). Nesse contexto teórico, nosso objeto de estudo, a cidade, se coloca culturalmente como uma comunidade emocional, de domínio dos seus habitantes, porém, está no território apropriado o centro de onde emana o entendimento do que é o todo urbano.This report tries to understand the city through the look of young people that lives in a place expose to poverty conditions. What move us to try understand how, starting to the feelings, those young people are able to construct in interaction process in and with urban space, the perception of city to the notice their identities in it. To characterization of this city, that we decide to call “emotion city”, so was collected representations that they usually express at drawings and speeches about the urban space, since they are captured images at collective imaginary of the habitants. The objective of this research has been to try understand the living area to the Rio de Janeiro, through to young peoples’ perceptive processes bring up urban complexity as they reveal identity territory and daily experiences. Therefore, this young people’s interactional relation became itself at one of most important parts at development for the individual that was analyzed having at base Vygotski’s idea (1998). This theory context, our object of study, the city, take itself culturally as one emotional neighborhood, of habitants’ domain, although it is in a territory belongs to the city habitants, the center where the knowledge come from that is the all urban

The influence of shock pressure, pre-shock temperature, and host rock composition on the survival rate of endolithic microorganisms during impact ejection from Mars

Petrographic and biological analysis of shock recovery experiments confirms the possible life transport due to an impact from Mars to Earth