Quantum entanglement distribution with 810 nm photons through telecom fibers

We demonstrate the distribution of polarization entangled photons of wavelength 810 nm through standard telecom fibers. This technique allows quantum communication protocols to be performed over established fiber infrastructure, and makes use of the smaller and better performing setups available around 800 nm, as compared to those which use telecom wavelengths around 1550 nm. We examine the excitation and subsequent quenching of higher-order spatial modes in telecom fibers up to 6 km in length, and perform a distribution of high quality entanglement (visibility 95.6%). Finally, we demonstrate quantum key distribution using entangled 810 nm photons over a 4.4 km long installed telecom fiber link.Comment: 5 pages, 5 figures, 1 tabl

Information complementarity in quantum physics

We demonstrate that the concept of information offers a more complete description of complementarity than the traditional approach based on observables. We present the first experimental test of information complementarity for two-qubit pure states, achieving close agreement with theory; We also explore the distribution of information in a comprehensive range of mixed states. Our results highlight the strange and subtle properties of even the simplest quantum systems: for example, entanglement can be increased by reducing correlations between two subsystems.Comment: 6 pages, 7 figures (including supplementary material

Discrete single-photon quantum walks with tunable decoherence

Quantum walks have a host of applications, ranging from quantum computing to the simulation of biological systems. We present an intrinsically stable, deterministic implementation of discrete quantum walks with single photons in space. The number of optical elements required scales linearly with the number of steps. We measure walks with up to 6 steps and explore the quantum-to-classical transition by introducing tunable decoherence. Finally, we also investigate the effect of absorbing boundaries and show that decoherence significantly affects the probability of absorption.Comment: Published version, 5 pages, 4 figure

On growth and morphology of tio2 nanotubes on ti6al4v by anodic oxidation in ethylene glycol electrolyte: Influence of microstructure and anodization parameters

Different studies demonstrated the possibility to produce TiO2 nanotubes (TNTs) on Ti6Al4V alloy by electrochemical anodization. However, the anodizing behavior of \u3b1 and \u3b2-phases in organic electrolytes is not yet clarified. This study reports on the anodizing behavior of the two phases in an ethylene glycol electrolyte using different applied potentials and anodizing times. Atomic force and scanning electron microscopies were used to highlight the anodic oxides differences in morphology. It was demonstrated that the initial compact oxide grew faster over the \u3b2-phase as the higher Al content of the \u3b1-phase caused its re-passivation, and the higher solubility of the V-rich oxide led to earlier pores formation over the \u3b2-phase. The trend was inverted once the pores formed over the compact oxide of the \u3b1-phase. The growth rate of the \u3b1-phase TNTs was higher than that of the \u3b2-phase ones, leading to the formation of long and well defined nanotubes with thin walls and a honeycomb tubular structure, while the ones grown over the \u3b2-phase were individual, shorter, and with thicker walls

Two-photon quantum walks in an elliptical direct-write waveguide array

Integrated optics provides an ideal test bed for the emulation of quantum systems via continuous-time quantum walks. Here we study the evolution of two-photon states in an elliptic array of waveguides. We characterise the photonic chip via coherent-light tomography and use the results to predict distinct differences between temporally indistinguishable and distinguishable two-photon inputs which we then compare with experimental observations. Our work highlights the feasibility for emulation of coherent quantum phenomena in three-dimensional waveguide structures.Comment: 8 pages, 7 figure

Characterization of an antioxidant and antimicrobial extract from cool climate, white grape marc

Valorization of agricultural waste has become increasingly important. Wastes generated by wineries are high in phenolic compounds with antioxidant and antibacterial properties, which contribute to phytotoxicity, making their immediate use for agricultural means limited. Utilizing a water-based extraction method, the phenolic compounds from winery waste were extracted and purified. The resulting extract was characterized for phenolic composition using high-pressure liquid chromatography-ultraviolet/visible and electrochemical detectors (HPLC-UV/Vis, ECD) for monomers, and spectral assessment of the tannins present using attenuated total reflectance-Fourier transform infrared (ATR-FTIR), FT-Raman, and solid-state nuclear magnetic resonance (SSNMR) spectroscopies. The extract\u2019s antioxidant activity was assessed by the scavenging of the 2,2-diphenyl-1\u2013picrylhydrazyl (DPPH) radical and Folin-Ciocalteu total phenolic assay, and was found to be as effective as a commercially obtained grape extract. The extract\u2019s antimicrobial efficacy was tested for minimum bactericidal concentration using Candida albicans, Escherichia coli 25922, and Staphylococcus aureus 6538, which resulted in greater efficacy against gram-positive bacteria as shown over gram-negative bacteria, which can be linked to both monomeric and tannin polyphenols, which have multiple modes of bactericidal action

Psychosocial impact of human papillomavirus on women's sexual dissatisfaction and quality of life

Purpose: This study assessed how psychological, socio-demographic and clinical variables were associated and moderated the relationship between sexual dissatisfaction and the psychosocial impact of the human papillomavirus (HPV) on the quality of life (QOL) of infected women. Methods: A cross-sectional design was used with a sample of 194 women. Participants completed a sociodemographic and clinical questionnaire, and were assessed on the psychosocial impact of HPV on quality of life (HPV Impact Profile), sexual dissatisfaction (Index of Sexual Satisfaction), psychological morbidity (Hospital Anxiety and Depression Scale), emotional suppression (Courtauld Emotional Control Scale) and spirituality (Spiritual and Religious Attitudes in Dealing with Illness). Results: Women with greater psychological morbidity and emotional suppression showed greater psychosocial impact of HPV on QOL. Greater psychological morbidity and emotional suppression, being older, having less education and not using condoms were associated with greater sexual dissatisfaction. Sexual dissatisfaction, psychological morbidity and age were associated with the impact of HPV on QOL. The variables that contributed to sexual dissatisfaction were age, emotional suppression and condom use. The use of condoms moderated the relationship between emotional suppression and sexual dissatisfaction. Conclusion: Interventions should focus on psychological morbidity and condom use, particularly in older and less educated women

Distributing entanglement and single photons through an intra-city, free-space quantum channel

We have distributed entangled photons directly through the atmosphere to a receiver station 7.8 km away over the city of Vienna, Austria at night. Detection of one photon from our entangled pairs constitutes a triggered single photon source from the sender. With no direct time-stable connection, the two stations found coincidence counts in the detection events by calculating the cross-correlation of locally-recorded time stamps shared over a public internet channel. For this experiment, our quantum channel was maintained for a total of 40 minutes during which time a coincidence lock found approximately 60000 coincident detection events. The polarization correlations in those events yielded a Bell parameter, S=2.27/pm0.019, which violates the CHSH-Bell inequality by 14 standard deviations. This result is promising for entanglement-based free-space quantum communication in high-density urban areas. It is also encouraging for optical quantum communication between ground stations and satellites since the length of our free-space link exceeds the atmospheric equivalent.Comment: 8 pages including 1 figure and 2 tables. The first two authors contributed equally to this wor

RIPARIAN FOREST ENVIRONMENTAL DIAGNOSIS: AN INTEGRATED ANALYSIS OF BOTANICAL AND METEOROLOGICAL PARAMETERS AS WELL AS ATMOSPHERIC AIR GENOTOXICITY

The environmental assessment of three riparian forest fragments in the upper (CA), medium (TA) and lower (CB) sections of the Sinos River, in the southern part of Brazil was carried out by applying an integrated analysis of botanic al and meteorological parameters as well as the atmospheric air genotoxicity. The analysis showed that the riparian forest at CA site had a greater number of trees that were taller, occupying a more basal area, supporting a higher epiphytic richness. Moreover, the air genotoxicity and the amount of rainfall were higher than at TA and CB sites. Considering that the organism responses are influenced by environmental conditions, the indicators analyzed supported the idea that the riparian forest at CA site is still a reference area, especially evidenced by the high richness of vascular epiphytes, including species susceptible to humandisturbance and by the absence of genotoxic risk.O diagnóstico ambiental de três fragmentos de mata ciliar nos trechos superior (CA), médio (TA) e inferior (CB) do Rio dos Sinos, no sul do Brasil, foi realizado a partir de uma análise integrada de parâmetros botânicos, meteorológicos e da genotoxicidade do ar atmosférico. A análise demonstrou que em CA a mata ciliar apresentou um maior número de árvores, mais altas, com maior área basal, suportando uma riqueza epifítica maior. Além disso, a genotoxicidade do ar e o volume de precipitação de chuva foram superiores a TA e CB. Considerando que as respostas dos organismos são influenciadas pelas condições ambientais, os indicadores analisados sustentam a ideia de que a mata ciliar de CA ainda é uma área de referência, evidenciada principalmente pela elevada riqueza de epífitos vasculares incluindo espécies sensíveis às perturbações antrópicas, e pela ausência de risco genotóxico

Heat Treated NiP–SiC Composite Coatings: Elaboration and Tribocorrosion Behaviour in NaCl Solution

Tribocorrosion behaviour of heat-treated NiP and NiP–SiC composite coatings was investigated in a 0.6 M NaCl solution. The tribocorrosion tests were performed in a linear sliding tribometer with an electrochemical cell interface. It was analyzed the influence of SiC particles dispersion in the NiP matrix on current density developed, on coefficient of friction and on wear volume loss. The results showed that NiP–SiC composite coatings had a lower wear volume loss compared to NiP coatings. However, the incorporation of SiC particles into the metallic matrix affects the current density developed by the system during the tribocorrosion test. It was verified that not only the volume of co-deposited particles (SiC vol.%) but also the number of SiC particles per coating area unit (and consequently the SiC particles size) have made influence on the tribocorrosion behaviour of NiP–SiC composite coatings