Abstract
Food labelling is a means of communication between food business operators and consumers, representing an important factor in consumer purchasing decisions. The enforcement of the new food labelling policy is aimed to improve food safety and public health through the mandatory indication of information and nutritional values. To understand the usefulness of the information provided for consumers, a survey was carried out to assess the efficacy of the information presented in food labelling. Principal component analysis was performed to obtain a smaller number of uncorrelated factors regarding the usefulness of food labelling. Results showed consumers usually do not read food labels due to lack of time and excessive information. Additionally, food labelling was observed to be more useful for specific consumer groups, such as, athletes, consumers with health conditions or consumers concerned with a healthy lifestyle. The results of the present study highlight the need of information campaigns by public health authorities to show the importance and advantages of reading food labels as well as the development of essential information which should be quickly and clearly seen and understood by consumers.

Abstract
Cyclic voltammetry and controlled-potential electrolysis have been employed to investigate the reductive intramolecular cyclization of propargyl bromoethers derivatives, catalyzed by electrogenerated (1,4,8,11-tetramethyl-1,4,8,11-tetraaza-cyclotetradecane) nickel(I), [Ni(tmc)](+), as the catalyst, in N,N,N-trimethyl-N-(2-hydroxyethyl) ammonium bis(trifluoromethylsulfonyl) imide, [N-1 1 1 2(OH)][NTf2] and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide, [C(2)mim][NTf2] in the absence and in the presence of water. The results show that the reaction leads to the formation of the expected heterocyclic compounds, in moderate to good yields. These compounds are important intermediates in the synthesis of natural products with possible biological activities. (C) 2019 The Electrochemical Society.

Abstract
Objective: The principal goal of this study was to investigate the uptake and distribution of lead (Pb) in the horns of Pb-dosed goats, and to explore possible links to their historical Pb dosing records. Horn is a keratinized material that grows in discrete increments with the potential to preserve the historical record of past environmental exposures. While previous studies have leveraged this potential to examine environmental and biological phenomena in horns, Pb uptake has never been explored. Methods: Horns were collected post-mortem from three goats that had been previously used to produce blood lead reference materials for the New York State proficiency testing program. The animals were periodically dosed with lead acetate, administered orally in a capsule, over a 5 to 8-year period. Horn cross sections were taken from each animal and analyzed using synchrotron radiation-induced micro X-ray fluorescence spectrometry (SR-ARE) at the Cornell High Energy Synchrotron Source (CHESS). Results: Elemental distribution maps were obtained by SR-mu XRF for Pb, Ca, S, Se, and three other elements (Br, Zn and Cu), with values reported quantitatively as a mass fraction (mu g/g for trace elements and mg/g for Ca and S). Accumulations of Pb were clearly visible as a series of narrow "rings" in each of the horn samples analyzed. The elements Ca, S, Br, Zn, and Cu were also detected as discrete rings within each cross-section, with Br strongly correlated with S in the samples examined. A marginal increase in Se may coincide with Pb accumulation in horn cross-sections. Annual mineralization estimates based on the relative distribution of Ca and S were used to establish a tentative timeline for horn growth, with each timeline linked to the pattern of Pb accumulation in the corresponding horn cross-section sample. Conclusions: Following ingestion, absorbed Pb is eventually deposited into caprine horns, resulting in discrete accumulations or "rings." Elemental mapping by SR-mu XRF clearly show Ca-rich layers that vary with annual periodicity, consistent with previous reports of horn mineralization. Localized enrichment of Cu, Zn, Br and S appear to coincide with the keratinized regions related to the annual growth ring pattern in horns. Spatial analysis of horns for Pb accumulation may be useful as a qualitative marker of time-resolved exposures that may reflect specific periods of acute Pb absorption.

Abstract
A reflective fiber optic sensor based on multimode interference for the measurement of relative humidity (RH) is proposed and experimentally demonstrated. The proposed probe is fabricated by fusion-splicing, approximately 30 mm long coreless fiber section to a single mode fiber. A hydrophilic agarose gel is coated on the coreless fiber, using the dip coating technique. When the incident light comes from the SMF to the CSF, the high-order modes are excited and propagate within the CSF. These excited modes interfere with one another as they propagate along whole CSF length, giving rise to a multimode interference (MMI). Since the effective refractive index of the agarose gel changes with the ambient relative humidity, as the environmental refractive index changes, the propagation constants for each guided mode within the CSF will change too, which leads to shifts in the output spectra. The proposed sensor has a great potential in real time RH monitoring, exhibiting a large range of operation with good stability. For RH variations in the range between 60 %RH and 98.5 %RH, the sensor presents a maximum sensitivity of 44.2 pm/%RH, and taking in consideration the interrogation system, a resolution of 1.1%RH is acquired. This sensor can be of interest for applications where a control of high levels of relative humidity is required.

Abstract
Strain and temperature are critical parameters to monitor in Li-ion batteries (LIBs) to improve their safety and long-term cycling stability. High local current densities can result in a massive heat release, decomposition of the electrolyte, gas evolution and even explosion of the battery cell, known as thermal runaway. However, the corrosive chemical environment in the batteries is a challenge to monitor strain and temperature. Optical fiber sensors, due to their high chemical stability and small diameter, can be embedded within the LIBs, thus becoming an interesting solution for operando and in situ measurements. In this work, a hybrid sensing network constituted by fiber Bragg gratings and Fabry-Perot cavities is proposed for the discrimination of strain and temperature. The proof-of-concept was performed by attaching the sensing network to the surface of a smart phone battery. Afterwards, it was embedded in a Li-ion pouch cell to monitor and simultaneously discriminate internal strain and temperature variations in three different locations. Higher thermal and strain variations are observed in the middle position. The methodology presented proves to be a feasible and non-invasive solution for internal, real-time, multipoint and operando temperature and strain monitoring of LIBs, which is crucial for their safety.

Abstract
With the present work, the development of fiber optic sensor solutions for the application in challenging media was intended. New sensor structures based on the post-processing of optical fibers were addressed, taking into account their sensitivity to variations in the external environment. In a first stage, fiber Bragg gratings were embedded in lithium batteries, to monitor temperature in situ and operando. Due to the harsh chemical environment of the battery, fiber optic sensors revealed to be the most advantageous alternative, when comparing to the electronic sensors. Fiber sensors exhibited good sensitivities and fast responses, besides being less invasive, thus they did not compromise the battery response. Furthermore, they were chemically stable. Still in the framework of this theme, and with the objective of monitoring possible strain and pressure variations inside the batteries, new sensors based on in-line Fabry-Perot cavities have been proposed. These sensors were characterized in lateral load, strain, and temperature. In a later stage, the study focused on the development of configurations that allowed to obtain high-resolution and/or sensitivity sensors. One of such configurations was obtained by creating a hollow microsphere at the fiber tip. The sensor was used to detected concentration variations and refractive index of glycerin and water mixtures. The influence of the diaphragm size in the sensor response was also studied, as well as the temperature response. New sensors based on multimode interference have also been characterized, using a coreless silica fiber tip. First, the influence of different parameters, such as length and diameters were analyzed. The sensors were tested in different solutions of glucose and water. It was observed that the sensor diameter is a decisive factor in obtaining devices that are more sensitive to refractive index and, consequently, to concentration. The determination of the thermo-optic coefficient of water/ethanol mixtures was also addressed using a multimode fiber interferometer sensor. Finally, a multimode interferometer sensor was functionalized by depositing agarose throughout the structure, allowing to optimize the response of the sensors to the external environment.;Com o presente trabalho pretendeu-se explorar soluções de sensores em fibra ótica para a aplicação em meios desafiantes. Novas estruturas sensoras baseadas em pós-processamento de fibra ótica foram abordadas, tendo em consideração a sua sensibilidade a variações do meio externo. Numa primeira etapa, foram embebidas redes de Bragg no interior de baterias de lítio, para monitorizar variações de temperatura in situ e operando. Devido ao complexo meio químico da bateria, os sensores em fibra ótica revelaram ser uma alternativa mais vantajosa em relação aos sensores elétricos, não só pela sensibilidade e rápida resposta, mas também pelo fato de não afetarem o desempenho da bateria. Além disso, os sensores usados revelaram ser pouco invasivos e quimicamente estáveis. Ainda no âmbito deste tema, e com o objetivo de monitorizar possíveis deformações e variações de pressão no interior da bateria de lítio, foram desenvolvidos novos sensores baseados em cavidades de Fabry-Perot do tipo in-line. Esses sensores foram caraterizados em pressão lateral, deformação e temperatura. Numa fase posterior, o estudo centrou-se no desenvolvimento de configurações que permitissem a obtenção de sensores com elevada resolução e/ou sensibilidade. Uma das configurações consistiu na formação de uma microesfera oca na ponta de uma fibra ótica. Esse sensor foi utilizado para detetar variações de concentração e índice de refração de misturas de glicerina e água. A influência do tamanho do diafragma na resposta do sensor também foi estudada, assim como a resposta em temperatura. Em seguida, desenvolveram-se novos sensores baseados em interferência multimodo, utilizando para tal uma ponta de fibra de sílica sem núcleo. Numa primeira abordagem analisou-se a influência de diferentes parâmetros, como o comprimento e o diâmetro dos sensores. Os sensores foram expostos a diferentes soluções de glucose e água. Verificou-se que o diâmetro do sensor é um fator decisivo para a obtenção de dispositivos mais sensíveis ao índice de refração e, consequentemente, à concentração. Foi também desenvolvido um sensor baseado em interferência multimodo que permitiu determinar o coeficiente termo-ótico de misturas de etanol e água. Por fim, procedeu-se à funcionalização de um sensor baseado em interferência multimodo através da deposição de agarose ao longo da estrutura, permitindo assim otimizar a sua resposta a variações do meio externo.