Dynamic curvature sensing using time expanded ΦOTDR.

Shape sensing can be accomplished using optical fiber sensors through different interrogation principles such as fiber Bragg gratings, optical frequency-domain reflectometry (OFDR), or optical time-domain reflectometry (OTDR). These techniques are either not entirely distributed, have poor performance in dynamic sensing, or are only valid for few-meter-long fibers. Here, we present a system able to perform distributed curvature sensing with a range of 125 m, 10-cm resolution, and a sampling rate of 50 Hz. This is done by interrogating three cores of a multi-core fiber (MCF) with the novel, to the best of our knowledge, time-expanded phase-sensitive (TE-Φ)OTDR technique. This system fills a performance gap in fiber shape sensors, opening the door to applications in civil engineering, medicine, or seismology.

Study of degradation of norfloxacin antibiotic and their intermediates by natural solar photolysis.

In this work, the photolysis of the antibiotic norfloxacin (NOR) and the formation of its photodegradation products were studied using UV and solar radiation. Their extraction was also assessed in Milli-Q water and secondary effluents from a wastewater treatment plant. The photolysis of NOR was chromatographically monitored. The structure of each degradation product is related to the reaction of NOR with reactive oxygen species (ROS), as confirmed using radical quenchers and mass spectrometry. Additionally, the feasibility of extracting NOR and its degradation products was assessed using a commercial solid phase extraction system. Photolysis results showed the formation of five degradation products, generated under exposure to both types of radiation. The decays in NOR concentrations for the solar and UV treatments were adjusted to pseudo first-order kinetics with apparent constant values of ksolar = 1.19 × 10-3 s-1 and kUV = 3.84 × 10-5 s-1. Furthermore, the superoxide radical was the main participant species in the formation of the degradation products P3, P4, and P5. Species P1 and P2 do not need this radical for their formation. The presence of NOR in water opens the possibility of its photolysis by solar radiation. This work contributes to the understanding of the mechanisms that mediate its photodegradation, in addition to studying potential options for its determination and its photodegradation products in the sample treatment.

Dual electro-optic comb spectroscopy using a single pseudo-randomly driven modulator.

We present a dual-comb scheme based on a single intensity modulator driven by inexpensive board-level pseudo-random bit sequence generators. The result is a simplified architecture that exhibits a long mutual coherence time (up to 50 s) with no need of stabilization feedback loops or self-correction algorithms. Unlike approaches that employ ultrafast arbitrary waveform generators, our scheme makes it possible to produce long interferograms in the time domain, reducing the difference in the line spacing of the combs even below the hertz level. In order to check the system accuracy, we report two spectroscopic measurements with a frequency sampling of 140 MHz. All these results are analyzed and discussed to evaluate the potential of our scheme to implement a field-deployable dual-comb generator.

Relaciones de pareja homosexual y heterosexual: un estudio comparativo

Esta investigación tiene el propósito de evaluar y comparar a personas heterosexuales y homosexuales, con relaciones de pareja estables, respecto a los componentes de la teoría triangular del amor, tácticas de resolución de conflictos, ajuste con la pareja y bienestar psicológico. Participaron 157 adultos jóvenes chilenos, 77 homosexuales (30 lesbianas y 47 gays) y 80 heterosexuales (45 mujeres y 35 hombres). Se utilizaron la Escala de Ajuste Diádico, la Escala Triangular del Amor de Sternberg, la Flourishing Scale de Diener y el Conflict Resolution Style Inventory de Kurdek. Los resultados muestran algunas diferencias significativas en tácticas de resolución de conflicto, componentes del amor y ajuste en la pareja, según la orientación sexual; además existen diferencias entre las mujeres que conviven y no conviven.

The aim of this study was to evaluate and compare heterosexual and homosexual people who are in stable relationships, with respect to the components of the triangular theory of love: conflict resolution tactics, couple adjustment and psychological wellbeing. The participants were comosed of 157 young adults Chileans: 77 homosexuals (30 lesbians and 47 gay men) and 80 heterosexuals (45 women and 35 men). The instruments used were the Dyadic Adjustment Scale, the Sternberg's Triangular Love Scale, the Flourishing Scale of Diener and Conflict Resolution Style Inventory of Kurdek. The results show that there are significant differences in some conflict resolution tactics, components of love between partners, and couple adjustment according to sexual orientation. In addition, there are also differences between women living and not living with a partner.