Production of optical phase space vortices with non-locally distributed mode converters

Optical vortices have been observed in a wide variety of optical systems. They can be observed directly in the wavefront of optical beams, or in the correlations between pairs of entangled photons. We present a novel optical vortex which appears in a non-local plane of the two-photon phase space, composed of a single degree of freedom of each photon of an entangled pair. The preparation of this vortex can be viewed as a "non-local" or distributed mode converter. We show how these novel optical vortices of arbitrary order can be prepared in the spatial degrees of freedom of entangled photons.Comment: To appear in upcoming special issue "Orbital Angular Momentum" of the Journal of Optic

Single observable concurrence measurement without simultaneous copies

We present a protocol that allows us to obtain the concurrence of any two qubit pure state by performing a minimal and optimal tomography of one of the subsystems through measuring a single observable of an ancillary four dimensional qudit. An implementation for a system of trapped ions is also proposed, which can be achieved with present day experimental techniques.Comment: 4 pages, 1 figur

Recuit laser de cellules solaires fonctionnant sous concentration

La résistance série élevée des cellules conventionnelles au silicium rend leur fonctionnement difficile sous concentration. Nous montrons ici que l'irradiation de la couche superficielle diffusée par un faisceau laser pulsé de grande intensité permet de réduire notamment la résistance série, de sorte que des rendements de conversion de 15 % sous 30 soleils et de 12,5 % sous 100 soleils (10 W/cm2) sont prévus par le calcul

Programa de sincronização do estro com cloprostenol em caprinos: dose efeito apos administração intramuscular superficial vulvar.

Noventa e nove cabras foram inseminadas artificialmente(IA) durante 12 dias com semen congelado. Nos primeiros seis dias, 50 cabras(50,5%) foram IA sob estro natural(controle), enquanto que as 49 restantes(49,5%) receberam o cloprostenol como segue: T1- 100mg intramuscular(IM) e T2, T3 e T4- 100, 50 e 25mg intramuscular superficial vulvar(IMSV). a taxa de nao-retorno ao estro aos 42 dias(TNR42) e a fertilidade ao parto nao apresentaram diferencas significativas entre os tratamentos e entre estes e o controle, ficando em 41,7 e 8,3%, 50,0 e 40,0%, 54,6 e 18,2%, 36,4 e 0,0% e 64,0 e 24,0% respectivamente, para T2, T3, T4 e controle. Durante os 12 dias do programa, 95,0% das cabras apresentaram estro, sendo qeu a TNR42 foi de 55,3% e a fertilidade ao parto de 27,7% Verificou-se que a via IMSV e uma alternativa efetiva na aplicacao do cloprostenol

Stoics against stoics in Cudworth's "A Treatise of Freewill"

In his 'A Treatise of Freewill', Ralph Cudworth argues against Stoic determinism by drawing on what he takes to be other concepts found in Stoicism, notably the claim that some things are ‘up to us’ and that these things are the product of our choice. These concepts are central to the late Stoic Epictetus and it appears at first glance as if Cudworth is opposing late Stoic voluntarism against early Stoic determinism. This paper argues that in fact, despite his claim to be drawing on Stoic doctrine, Cudworth uses these terms with a meaning first articulated only later, by the Peripatetic commentator Alexander of Aphrodisias

Entropic Entanglement Criteria for Continuous Variables

We derive several entanglement criteria for bipartite continuous variable quantum systems based on the Shannon entropy. These criteria are more sensitive than those involving only second-order moments, and are equivalent to well-known variance product tests in the case of Gaussian states. Furthermore, they involve only a pair of quadrature measurements, and will thus should prove extremely useful the experimental identification of entanglement.Comment: 4 pages, 2 figure

The Impact of American Petroleum Institute Certifications in Quality Management Systems: Analysis of API Spec Q1 and Q2 Certified Organizations

The present study aims to provide initial insight into the quality management system. More precisely, it describes whether and to what extent implementation of Quality Management System according to API Spec Q1 and/or Q2 can impact various companies in the oil and gas industry. A sample of international organizations is surveyed to understand how certifications affect organizational culture, passing through elements such as competitiveness, reputation, organizational performance, costs, and others. In addition to the certification itself, a rigorous and challenging process of implementation, review, restructuring is carried out, involving fundamental elements of the organization. During this stage, technical support becomes essential for a productive consolidation of the required requirements, and later, the improvement scenario is indispensable to maintain all the success factors in order to consolidate a quality management system within the organization. Thus, based on the findings, companies in the oil and gas segment may identify and reflect on the certification benefits to improve their approach to quality management systems, given the observations of managers and operational interviewees

Reptiles, Squamata, Parque Natural Municipal da Taquara, municipality of Duque de Caxias, state of Rio de Janeiro, Southeastern Brazil

Herein we report a list of the reptiles from Parque Natural Municipal da Taquara, municipality of Duque deCaxias, state of Rio de Janeiro, southeastern Brazil, an area situated in the Atlantic Rainforest Domain. The study wascarried out from September 2006 to October 2008. We recorded 31 species of Squamate reptiles: one species of thefamily Amphisbaenidae; eight species of lizards of the families Anguidae (n = 1), Gekkonidae (1), Phyllodactylidae (1),Polychrotidae (1), Scincidae (1), Teiidae (2), and Tropiduridae (1); and 22 species of snakes of the families Boidae (2),Colubridae (6), Dipsadidae (11), Elapidae (1), and Viperidae (2). Our study indicates that the PNMT is an important area forthe conservation of the Squamate reptile assemblages that inhabit lowlands of Atlantic Rainforest in Brazil