High-power collective charging of a solid-state quantum battery

Quantum information theorems state that it is possible to exploit collective quantum resources to greatly enhance the charging power of quantum batteries (QBs) made of many identical elementary units. We here present and solve a model of a QB that can be engineered in solid-state architectures. It consists of $N$ two-level systems coupled to a single photonic mode in a cavity. We contrast this collective model ("Dicke QB"), whereby entanglement is genuinely created by the common photonic mode, to the one in which each two-level system is coupled to its own separate cavity mode ("Rabi QB"). By employing exact diagonalization, we demonstrate the emergence of a quantum advantage in the charging power of Dicke QBs, which scales like $\sqrt{N}$ for $N\gg 1$.Comment: 8 pages, 5 figures. Version v2 supersedes version v1 where a technical mistake was done in using the Holstein-Primakoff transformation. The quantum advantage in the maximum charging power discussed in version v1 has been found to be robust. We have also updated the list of author

L’éducation pour tous en Afrique de l’Ouest

Dix ans après Jomtien, on a pu noter à Dakar (avril 2000) que les objectifs proposés à la Conférence mondiale de l’éducation de 1990 – malgré quelques avancées – sont bien loin d’avoir été atteints. Parallèlement, le contexte mondial a changé aux plans économique et technologique, introduisant des paramètres nouveaux qu’il est nécessaire de prendre en compte. L’Afrique de l’Ouest est, quant à elle, en mesure de relever ces nouveaux défis.It was clear at Dakar in April 2000, ten years after Jomtien, that the objectives put forward at the World Conference on Education in 1990 are, despite some progress, far from having been reached. At the same time, economically and technologically speaking, the world context has changed, introducing new parameters which must be considered. As far as West Africa is concerned, the country is capable of meeting these challenges.Diez años después de Jomtien (Dakar, abril 2000), se puede notar que los objetivos propuestos durante la Conferencia mundial de la educación en 1990, no han sido alcanzados a pesar de algunos progresos. Paralelamente, el contexto mundial ha cambiado desde el punto de vista económico y tecnológico con nuevos parámetros. África del Oeste es capaz de tomarlos en cuenta

Learning, Social, and Psychological Outcomes of Students with Moderate, Severe, and Complex Disabilities in Inclusive Education: A Systematic Review

The purpose of this systematic review was to investigate the learning, social, and psychological outcomes of students with moderate, severe, and complex disabilities (MSCD) in inclusive settings. The review discusses barriers to conducting rigorous research in this field. Whilst an initial literature search located 1,338 records, only 18 were finally included due to the eligibility criteria. Studies were placed in categories based on the topics investigated. Regarding learning outcomes of students with MSCD, findings were moderately in favour of school inclusion for both academic achievement and adaptive skills. Regarding social outcomes, results showed that inclusive settings offer more access to instructional time and peer interaction, although they reported marginalisation during class activities and social isolation within the peer group. Finally, in terms of psychological outcomes, inclusive settings appeared to reduce the frequency of challenging behaviours. The paper also addresses conceptual barriers regarding the definition of inclusion and its consequences on research and practice as well as research design barriers resulting from the quality of research in this field. Based on review results, this paper outlines epistemological propositions for developing standards of quality for both research and practice in the field

Introduction

L’école en milieu rural fait l’objet, dans de nombreux pays, de débats d’autant plus passionnés qu’ils sont associés à des enjeux économiques et sociaux. Moins fréquemment évoquée que celle du secteur scolaire urbain, et cependant tout aussi liée aux transformations du monde contemporain, l’adaptation de l’école rurale ne se réalise certes pas sans heurts ni polémiques – il n’est que de penser au difficile problème de la fermeture d’établissements. Mais la confrontation aux évolutions actuell..

Analysis of Dust Fires and Explosions in the Food Processing Industry

Nearly all solid granular foods and powdered ingredients, such as sugar, flour, grain, spices, starch, and powdered flavors, have the capacity to sustain a combustion. This may result often in dust fires, originating from dust layers and heaps, and sometimes also in violent explosions, when the dust is suspended and a cloud is formed. Many factors affect the explosion violence or the ignition sensitivity of a dust cloud: these can be related to physical properties of the solid material (particle size, moisture content, minimum ignition temperature, etc.) and to the geometry of the system involved in the explosion (closed vessels, long pipes, degree of turbulence, etc.). While the conditions to have an explosion occur rarely in processing buildings, hazardous dust clouds regularly form during bin filling, powder conveying, or dust collection. The scope of this paper is to review a selection of incidents occurred in the past involving solid food materials and analyze them against the current best industrial practices regarding explosion prevention and protection. Particular attention will be given to the analysis of potential ignition sources and their effectiveness in igniting the flammable dust atmosphere. A selection of “lessons learnt” will also be derived from the analysis of the incidents. Lastly, the paper shall discuss the most recent trends of combustible dust fires and explosions among other industry sectors (pharmaceutical, wood processing, chemical, energy production), to gain insights about potential areas of improvement to advance in people and plant safety

Hydrogen storage in rippled graphene: perspectives from multi-scale simulations

Exploring new perspectives for green technologies is one of the challenges of the third millennium, in which the need for non-polluting and renewable powering has become primary. In this context, the use of hydrogen as a fuel is promising, since the energy released in its oxidation (~285 kJ/mole) is three times that released, on average, by hydrocarbons, and the combustion product is water (Ramage, 1983). Being hydrogen a vector of chemical energy, efficient conservation and non-dispersive transportation are the main goals. Three issues must be considered to this respect: (i) storage capacity (ii) storage stability (iii) kinetics of loading/release. Commercial technologies are currently based on cryo-compression or liquefaction of H2 in tanks. These ensure quite a high gravimetric density (GD, point (i)), namely 8-13% in weight of stored hydrogen, and a relatively low cost (Z\"uttel 2003). However concerning points (ii) and (iii), these technologies pose problems of safety, mainly due to explosive flammability of hydrogen, and consequent unpractical conditions for transportation and use (Mori et al 2009). Therefore, research efforts are directed towards solid-state based storage systems (energy.gov, Bonaccorso et al 2015)

Analysis of Polyphenols in the Lamiaceae Family by Matrix Solid-Phase Dispersion Extraction Followed by Ultra-High-Performance Liquid Chromatography–Tandem Mass Spectrometry Determination

Polyphenolic compounds (PCs) are natural-occurring secondary metabolites with considerable physiological and morphological importance in plants and different biological functions. In this work, a matrix solid-phase dispersion extraction/purification procedure, followed by an ultra-high-performance liquid chromatography–tandem mass spectrometry analysis, has been developed and validated for the quantification of 17 PCs in Ocimum basilicum L., Origanum vulgare L., and Thymus vulgaris L. from the Lamiaceae family. The use of a limited sample amount, combined with small solvent consumption, marks the convenience of this technique for the extraction/isolation of compounds of interest. The validation showed good results, with recoveries ranged between 75 and 105%, relative standard deviation values ≤12%, and very low matrix effects. The experimental results demonstrated the variability of the phenolic pattern of the samples and the need for accurate assessment of the phenolic pattern to establish the real nutra..

Laboratórios de agrobiotecnologia: níveis de decisão em trajetórias de transferência de tecnologia

Historically the production of scientific knowledge in Argentina is characterized by a large gap between industry and scientific research. However, in recent years it can be seen premature cases of innovation which articulate relationships between researchers and companies. It is particulary interesting the study of agribiotechnology.The present work is carried out in the context of social studies of science and technology and it aims to analyze the trajectories of research and development laboratories cases which have projects in technology transfer to companies. The purpose is to characterize the strategies developed to guide their research in this direction.The general findings illustrate the existence of different levels of decision making that are key in achieving technology transfer. These decisions shape strategies which manage to coexist laboratory research and transfer.Históricamente la producción de conocimiento científico en Argentina se caracteriza por una gran separación entre el sector productivo y la investigación científica. Sin embargo, en los últimos años se puede observar incipientes casos de innovación que articulan relaciones entre los investigadores y empresas. Particularmente interesa estudiar el caso de la agrobiotecnología.Este trabajo se realiza en el marco de los estudios sociales de la ciencia y la tecnología y busca analizar las trayectorias de casos de laboratorios de investigación y desarrollo que tienen proyectos de transferencia tecnológica hacia empresas. El objetivo consiste en caracterizar las estrategias que desarrollan para orientar sus investigaciones en ese sentido.Las conclusiones generales ilustran la existencia de distintos niveles de decisión que resultan claves en la realización de la transferencia tecnológica. Esas decisiones conforman estrategias donde los laboratorios logran hacer coexistir actividades de investigación y transferencia.Historicamente a produção de conhecimento científico na Argentina é caracterizada por uma grande separação entre o setor produtivo e a investigação científica. No entanto, nos últimos anos podem se observar casos incipientes de inovação que articulam relações entre os investigadores e empresas. Particularmente interessa estudar o caso da agrobiotecnologia. Este trabalho é realizado no âmbito dos estudos sociais da ciência e a tecnologia e busca analisar as trajetórias de casos de laboratórios de pesquisa e desenvolvimento que têm projetos de transferência de tecnologia para empresas. O objetivo é caracterizar as estratégias desenvolvidas para orientar suas investigações nesse sentido. As conclusões gerais ilustram a existência de diferentes níveis de decisão que resultam fundamentais na realização da transferência de tecnologia. Essas decisões conformam estratégias onde os laboratórios conseguem fazer coexistir atividades de investigação e transferência

Estimation Accuracy of Polarization State from Coherent Receivers for Sensing Applications

We experimentally investigate on the intrinsic accuracy in fiber State of Polarization estimation from the DSP of commercial coherent tranceivers, in terms of angular uncertainty on the Poincaré’s sphere vs. received OSNRs, for sensing applications. We then demonstrate how using a moving average enhances accuracy