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Sorption has been proposed as a promising approach towards a sustainable water decontamination and recently to the recycling of rare earth elements (REE). Although living seaweed have been shown to be capable of removing REE from contaminated solutions, no studies have yet compared the effects of REE competition on sorption onto different groups of seaweed. These effects were analysed in the present study by exposing six living seaweeds (Ulva lactuca, Ulva intestinalis, Fucus spiralis, Fucus vesiculosus, Gracilaria sp. and Osmundea pinnatifida) (3 g/L, fresh weight) to mono-element and multi-element solutions of Y, La, Ce, Pr, Nd, Eu, Gd, Tb and Dy (1 μmol/L). Results show a preference towards light REE in mono-element solutions, which is reduced when in competition with other REE. The competitive effect is less pronounced in heavy REE indicating that these are still able to bind to the macroalgae despite the presence of competing ions. Contrary to water content (%), seaweed specific surface area (cm2/g) shows to be an important factor in the sorption of REE, since larger surface area is associated with higher removal and larger competitive effect.

In this article, two configurations are presented for simultaneous measurement of strain and temperature by reducing the cross-section area in small regions of the fiber where the Bragg gratings were inscribed, to achieve dual sensitivity to strain and handle the cross-sensitivity to temperature of a single grating. Each configuration used a single Bragg grating inscribed in a 2-ring undoped poly (methyl methacrylate) microstructured polymer optical fiber (mPOF) with a pulsed Q-switched Nd:YAG laser system. To reduce the cross-section area, a femtosecond laser system was used to remove portions of the mPOF, creating micromachined slots in the fiber, with different lengths for each configuration. The result was the appearance of a second peak when strain is applied, with a higher strain sensitivity. The thermal, humidity and refractive index response of these gratings were analyzed, revealing a thermal sensitivity almost twice the value of a common Bragg grating inscribed in the same mPOF. The maximum root mean square errors obtained when both strain and temperature are applied in these grating devices were 52 μϵ and 0.6 °C, respectively. These results show that the method used to produce these devices could be a suitable and reliable option to fabricate very compact sensors to simultaneously measure strain and other parameters, such as temperature. Moreover, these devices may be used as phase-shift gratings since the position of the reflective peaks and their relative spectral separation may be modulated by applying strain to the optical fiber.

PANDA-FBG sensors were used to track in real time simultaneous temperature and deformation changes in an 18650 Li-ion battery during their operation under normal and abusive conditions, for the first time.

[EN] In this work, we obtained chirped Bragg gratings by post-coating uniform poly (methylmethacrylate) (PMMA) microstructured polymer optical fiber Bragg gratings (POFBGs) with an UV cure adhesive. The main advantage of the proposed method consists on being a cost-effective and simple solution, since no special phase mask, addi tional etching or gradient thermal annealing are required. A comparison between the fabricated chirped Bragg grating¿s performance and previous reported methods in the literature is presented. As a compact sensor with two different active areas (adhesive coated and uncoated sections of the POFBG), the developed sensing device can be used for multiparameter sensing, namely for strain, humidity and temperature monitoring. Allying the proposed flexible and low-cost fabrication technique with the intrinsic characteristics of POFs, one may conclude that the developed sensor has high potential for multiparameter sensing in possible future engineering and biomedical applications., National Natural Science Foundation of China (62003046) ; The Spanish Ministerio de Ciencia, Innovacion y Universidades RTI2018-101658-B-I00 FOCAL Project; Guangdong Basic and Applied Basic Research Foundation (2021A1515011997) ; Guangdong Recruitment Program of Foreign Experts (2020A1414010393) ; C. Marques ac-knowledges Fundacao para a Ciencia e a Tecnologia (FCT) through the CEECIND/00034/2018 (iFish project) and this work was developed within the scope of the project i3N, UIDB/50025/2020 &UIDP/50025/2020, financed by national funds through the FCT/MEC. Luis Pereira and Tiago Paixao also acknowledge FCT for the grant with references SFRH/BD/146295/2019 and PD/BD/128265/2016, respectively.

In this work, a network of fiber sensors has been developed for real time, in situ, and in operando multipoint monitoring the surface temperature distribution on a smartphone Li-ion battery (LiB). Different temperature and relative humidity conditions are considered, in order to mimic the LiB response in the dry, temperate, and cold climates. In total, the temperature variations that occur in five different locations of the LiB are monitored, during constant current charge and different discharge rates, under normal and abusive operating conditions, performing a thermal spatial mapping of the battery surface. In general, the sensors detect temperature variations according to the voltage signal change and faster variations of voltage usually translate in higher temperature rise at the LiB surface. For instance, under abusive discharge, where the voltage drop is fast, the temperature increases at least twice when compared to the normal operating conditions. Absolute temperature values as high as (65.0 ± 0.1) °C are detected by the optical sensor located near the electrodes, under the higher discharge rate (5.77 C) and dry climate. A thermal gradient is identified from the top to the bottom on the LiB surface during the experimental tests. A lower battery performance is observed when it operates under the cold climate, with maximum temperature variations of (30.0 ± 0.1) °C for the higher discharge rate. These results can be helpful to design of next generation of LiBs, improving a faster cooling in critical areas, in order to reduce accumulated heat and preventing consequences such as thermal runaway and failure.

BackgroundVitamin D is a fundamental regulator of host defences by activating genes related to innate and adaptive immunity. Previous research shows a correlation between the levels of vitamin D in patients infected with SARS-CoV-2 and the degree of disease severity. This work investigates the impact of the genetic background related to vitamin D pathways on COVID-19 severity. For the first time, the Portuguese population was characterized regarding the prevalence of high impact variants in genes associated with the vitamin D pathways.MethodsThis study enrolled 517 patients admitted to two tertiary Portuguese hospitals. The serum concentration of 25 (OH)D, was measured in the hospital at the time of patient admission. Genetic variants, 18 variants, in the genes AMDHD1, CYP2R1, CYP24A1, DHCR7, GC, SEC23A, and VDR were analysed.ResultsThe results show that polymorphisms in the vitamin D binding protein encoded by the GC gene are related to the infection severity (p = 0.005). There is an association between vitamin D polygenic risk score and the serum concentration of 25 (OH)D (p = 0.042). There is an association between 25 (OH)D levels and the survival and fatal outcomes (p = 1.5e-4). The Portuguese population has a higher prevalence of the DHCR7 RS12785878 variant when compared with its prevalence in the European population (19% versus 10%).ConclusionThis study shows a genetic susceptibility for vitamin D deficiency that might explain higher severity degrees in COVID-19 patients. These results reinforce the relevance of personalized strategies in the context of viral diseases.Trial registrationNCT04370808

Three different types of strain and temperature sensors based on negative curvature hollow core fiber (NCHCF) are proposed. Each sensor is produced by splicing a small section of the NCHCF between two sections of single mode fiber. Different types of interferometers are obtained simply by changing the splicing conditions. The first sensor consists on a single Fabry-Perot interferometer (FPI). The remaining two configurations are attained with the same sensing structure, depending on its position in relation to the interrogation setup. Thus, a double FPI or a hybrid sensor, the latter being composed by an FPI and a Michelson interferometer, are formed. The inline sensors are of submillimeter size, thus enabling nearly punctual measurements.

The release of potentially toxic elements into the environment, and their effects on aquatic ecosystems still present a real threat. To avoid such contamination, the use of biological sorbents as an alternative to conventional and expensive water remediation techniques has been proposed. The present study evaluated the potential of 0.5 g L−1 of peanut, hazelnut, pistachio, walnut, and almond shells to remove the requisite concentrations of cadmium (Cd), lead (Pb), and mercury (Hg) from contaminated water. Hazelnut shells were identified as the sorbent with the highest potential and were evaluated in mono- and multi-contaminated mineral water. The influence of sorbent-intrinsic and solution-intrinsic characteristics were assessed. Differences among sorbents were attributed to varying percentages of their main components: cellulose, hemicellulose, and lignin. Matrix complexity increase caused a decrease in Cd removal, presumably due to the diminution in electrostatic interaction, and complexation with anions such as Cl-. When simultaneously present in the solution, contaminants competed, with Pb showing higher affinity to the sorbent than Hg. High efficiencies (&gt, 90%) obtained for hazelnut shells for all elements in ultrapure water and for Pb and Hg in mineral water) reveals the high potential of this low-cost and abundant waste for use in the remediation of contaminated waters (circular economy).

© The Author(s) 2021. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/., Vitamin D is a fundamental regulator of host defences by activating genes related to innate and adaptive immunity. Previous research shows a correlation between the levels of vitamin D in patients infected with SARS-CoV-2 and the degree of disease severity. This work investigates the impact of the genetic background related to vitamin D pathways on COVID-19 severity. For the first time, the Portuguese population was characterized regarding the prevalence of high impact variants in genes associated with the vitamin D pathways. This study enrolled 517 patients admitted to two tertiary Portuguese hospitals. The serum concentration of 25 (OH)D, was measured in the hospital at the time of patient admission. Genetic variants, 18 variants, in the genes AMDHD1, CYP2R1, CYP24A1, DHCR7, GC, SEC23A, and VDR were analysed. The results show that polymorphisms in the vitamin D binding protein encoded by the GC gene are related to the infection severity (p = 0.005). There is an association between vitamin D polygenic risk score and the serum concentration of 25 (OH)D (p = 0.04). There is an association between 25 (OH)D levels and the survival and fatal outcomes (p = 1.5e-4). The Portuguese population has a higher prevalence of the DHCR7 RS12785878 variant when compared with its prevalence in the European population (19% versus 10%). This study shows a genetic susceptibility for vitamin D deficiency that might explain higher severity degrees in COVID-19 patients. These results reinforce the relevance of personalized strategies in the context of viral diseases., This project was supported by the “Fundação para a Ciência e Tecnologia”, program “Research 4 Covid-19 Apoio especial a projetos de implementação rápida para soluções inovadoras de resposta à pandemia de COVID-19”. It was also partially supported by each institution.

Introduction: hepatic osteodystrophy, including osteoporosis, is an abnormal bone metabolism related with chronic liver diseases. Osteoporosis is associated with an increased risk of bone fractures, with a significant impact on morbidity, mortality and healthcare costs. Nevertheless, bone disorders tend to be undervalued in cirrhosis due to alcohol-related liver disease (ALD cirrhosis). This study aimed to assess the prevalence of hepatic osteodystrophy and osteoporosis in ALD cirrhosis. Methods: a prospective observational study was performed that included patients with ALD cirrhosis, between September 2017 and December 2018. Bone mineral density was determined by dual energy X-ray absorptiometry at the lumbar spine and the femoral neck. Hepatic osteodystrophy was defined as a T-score below -1 SD and osteoporosis as a T-score below -2.5 SD. Results: ninety-four patients were included; 24.5 % (n = 23) had prior fragility fractures and ten patients suffered new osteoporotic fractures during the study period. Hepatic osteodystrophy was diagnosed in 79.8 % (n = 75) and osteoporosis in 21.3 % (n = 20) of cases. Patients with hepatic osteodystrophy presented significantly worse Child-Turcotte-Pugh (p < 0.05) and Model for End-Stage Liver Disease (MELD-sodium) scores (p = 0.01). According to the multivariate analysis, lower body mass index (BMI) (OR = 0.787, 95 % CI: 0.688-0.901, p = 0.001) and vitamin D deficiency (OR = 6.798, 95 % CI: 1.775-26.038, p = 0.005) were significantly and independently associated with hepatic osteodystrophy. Patients with osteoporosis also had a lower BMI (p = 0.01). Female patients and those with prior fragility fractures were more likely to suffer from osteoporosis (p < 0.05). Conclusion: our study revealed a high prevalence of hepatic osteodystrophy and osteoporosis in patients with ALD cirrhosis (particularly in those with a lower BMI) and a concerning high rate of fragility fractures. Bone mineral density should be assessed in order to allow for an early diagnosis and the implementation of preventive measures.

Mercury is a very toxic metal that persists and accumulates in the living organisms present in the aquatic systems and its elimination is an urgent need. Two green (Ulva intestinalis and Ulva lactuca), brown (Fucus spiralis and Fucus vesiculosus), and red (Gracilaria sp. and Osmundea pinnatifida) marine macroalgae were tested for mercury removal from saline waters. The ability of each species was evaluated to the initial mercury concentrations of 50, 200, and 500 μg dm-3 along 72 h. In general, all species exhibited good performances, removing 80.9–99.9% from solutions with 50 μg dm-3, 79.3–98.6% from solutions with 200 μg dm-3, and 69.8–97.7% from solutions containing 500 μg dm-3 of mercury. Among the macroalgae, Ulva intestinalis showed the highest affinity to mercury and it presented an uptake ability up to 1888 μg g-1 of Hg(II) and bioconcentration factors up to 3823, which proved its promising potential on Hg removal.

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 smartphone 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.

This paper focuses on three main issues regarding Material Extrusion (MEX) Additive Manufacturing (AM) of thermoplastic composites reinforced by pre-functionalized continuous Nickel&ndash, Titanium (NiTi) wires: (i) Evaluation of the effect of the MEX process on the properties of the pre-functionalized NiTi, (ii) evaluation of the mechanical and thermal behavior of the composite material during usage, (iii) the inspection of the parts by Non-Destructive Testing (NDT). For this purpose, an optical fiber sensing network, based on fiber Bragg grating and a cascaded optical fiber sensor, was successfully embedded during the 3D printing of a polylactic acid (PLA) matrix reinforced by NiTi wires. Thermal and mechanical perturbations were successfully registered as a consequence of thermal and mechanical stimuli. During a heating/cooling cycle, a maximum contraction of &asymp, 100 &micro, m was detected by the cascaded sensor in the PLA material at the end of the heating step (induced by Joule effect) of NiTi wires and a thermal perturbation associated with the structural transformation of austenite to R-phase was observed during the natural cooling step, near 33.0 &deg, C. Regarding tensile cycling tests, higher increases in temperature arose when the applied force ranged between 0.7 and 1.1 kN, reaching a maximum temperature variation of 9.5 &plusmn, 0.1 &deg, C. During the unload step, a slope change in the temperature behavior was detected, which is associated with the material transformation of the NiTi wire (martensite to austenite). The embedded optical sensing methodology presented here proved to be an effective and precise tool to identify structural transformations regarding the specific application as a Non-Destructive Testing for AM.

In this work, the thermo-optic coefficient (TOC) of ethanol-water mixtures, through refractive index and temperature measurements are determined using an etched optical fiber tip based on a multimode interferometer. The proposed probe is fabricated by fusion-splicing a 5.2 mm long coreless fiber section to a single mode fiber. To reduce the sensor dimensions and improve its sensitivity towards external medium variations, the fiber tip is subjected to wet chemical etching using a solution of 40% hydrofluoric acid, presenting a final diameter of 24.4 μm. The TOC of each solution is estimated and, in the case of deionized water and pure ethanol, its value is of −1.128 × 10−4 °C−1 and −3.117 × 10−4 °C−1, respectively.

The aim of this study, enrolling 118 patients, was to clinically evaluate the accuracy of carotid pulse waveform acquisition with a new non-invasive optical fiber probe using invasive and non-invasive pressure readings as references. Pulse waves were acquired simultaneously in the ascending aorta and right common carotid; for the non-invasive study, the pulses were sequentially acquired using the optical fiber device and the Complior Analyse® (Alam Medical, France) device in the right carotid artery. For all subjects, the pulse waveforms assessed using the optical fiber sensor and the references were superimposed to analyze the deviation and point-by-point correlation. Augmentation index and central pressure were compared using intraclass correlation and Bland-Altman analyses with a confidence interval of 95%. For the invasive study, the acquired waves presented a mean deviation of 11 ± 3% and a mean intraclass correlation of 0.97 ± 0.02. Concerning the augmentation index and central systolic pressure, correlations of 0.79 (p

A fiber sensor based on a Fabry–Perot cavity is reported for measuring mixtures of water and glycerin. The sensor is fabricated by producing an air bubble near the end face of a multimode fiber section, and reshaping the tip in order to produce a thin silica diaphragm. It is observed that there is dependence between diaphragm dimensions and the structure sensitivity. The sensor with a 20 μm thick diaphragm presents a sensitivity of 7.81 pm/wt.% regarding the variation of water mass fraction in glycerin. With this sensing head, an experimental resolution of 2.5 wt.% is estimated. By converting the mass fraction into refractive index variations, a maximum sensitivity of 5.49 nm/RIU is obtained. Moreover, given the low-temperature sensitivity (1.6 pm/ °C), the proposed cavity should be adequate to perform temperature independent measurements. The purity degree of glycerin is one of the most important parameters to be determined in applications such as in pharmaceutical or cosmetic area. The proposed sensor can be an alternative to the previously developed ones.

A reflective fiber optic sensor based on multimode interference for the measurement of refractive index variations in glucose aqueous solutions is proposed. The sensor is fabricated by splicing a short section of coreless silica fiber to standard single mode fiber. The influence of the coreless fiber dimensions on the sensor performance is analyzed. By changing the sensor length, no significant impact is observed. However, the reduction of the sensing head diameter leads to a large improvement of the sensitivity. The smaller sensor, with a length of 5 mm and a diameter of 24 μm, presents a maximum sensitivity of 1467.59 nm/RIU, for the refractive index range between 1.364 and 1.397 RIU. Taking into account the acquisition system, a maximum theoretical resolution of 6.8 × 10 -5 RIU is achieved.

This study focused on the impact of 3 key variables (macroalgae mass, water salinity, and Nd(III) initial concentration) on the performance of two living macroalgae (Ulva sp. and Gracilaria sp.) in the removal and bioaccumulation of Nd(III), finding the optimal operating conditions through the Response Surface Methodology (RSM). Experiments were carried out in batch conditions stablished using a Box-Behnken design of 3 factors-3 levels (macroalgae mass of 0.5, 3.0 and 5.5 g dm-3; water salinity of 10, 20 and 30; and Nd(III) initial concentration of 10, 255 and 500 µg dm-3). The linear, quadratic and combined effects of the variables were described by RSM through a second order polynomial function. Optimized conditions were calculated by nonlinear regression using the Nelder-Mead simplex algorithm. Results evidenced the great capacity of both species to remove Nd(III), with removals around 80 % for the conditions: initial concentration of Nd(III) of 255 µg dm-3, water salinity 10, and macroalgae mass of 5.5 g dm-3. 3-D Response Surfaces showed that after 72 h of experiment, the most impactful variable on the removal process was the macroalgae mass. Regarding bioaccumulation, for the conditions studied, the higher the Nd(III) initial concentration the greater was its accumulation. The RSM tool made it possible to obtain the optimal conditions for both species, for contact times of 72 and 120 h. The proposed methodology can be applied in the recovery of Nd (which is a critical element) from contaminated waters, with the aim of its reintroduction in industrial production processes (recycling).

This work shows a comparative study between the thermocouples and fiber sensors response for the monitoring of temperature variations occurring in three different locations of a lithium battery. The battery is submitted to constant current charge and different discharge rates, under normal and abusive operating conditions. For this specific application, the results show that the fiber Bragg grating sensors have better resolution and a rise time 28.2% lower than the K‐type thermocouples, making them a better choice for the real time monitoring of the battery surface temperature as well as a useful tool for failure detection and an optimized management in batteries.

Background & Aims: Unsedated colonoscopy can be painful, poorly tolerated by patients, and associated with unsatisfactory technical performance. Previous studies report an advantage of water exchange over conventional air insufflation in reducing pain during unsedated colonoscopy. Our goal was to analyze the impact of water exchange colonoscopy on the level of maximum pain reported by patients submitted to unsedated colonoscopy, compared to conventional air insufflation. Methods: We performed a single-center, patient-blinded, prospective randomized comparative study, where patients were either allocated to the water group, in which the method of colonoscopy used was water exchange, or the standard air group, in which the examination was accomplished with air insufflation. Results: A total of 141 patients were randomized, 70 to the water and 71 to the air group. The maximum level of pain reported by patients during unsedated colonoscopy, measured by a numeric scale of pain (0-10), was significantly lower in the water group (3.39 ± 2.32), compared to the air group (4.94 ± 2.10), p < 0.001. The rate of painless colonoscopy was significantly higher in the water group (12.9 vs. 1.4%, p = 0.009). There were no significant differences between the two groups regarding indications for the procedure, quality of bowel preparation, cecal intubation time, withdrawal time, number of position changes, adenoma detection rate, and postprocedural complications. Only the number of abdominal compressions was significantly different, showing that water exchange decreases the number of compressions needed during colonoscopy. Conclusions: Water exchange was a safe and equally effective alternative to conventional unsedated colonoscopy, associated with less intraprocedural pain without impairing key performance measures. Introdução e objectivos: A colonoscopia sem sedação pode constituir um procedimento doloroso e mal tolerado pelo doente, associando-se a um desempenho técnico subóptimo. Vários estudos demonstraram o benefício do método de troca de água, comparativamente à colonoscopia convencional com insuflação de ar, na redução do nível de dor na colonoscopia sem sedação. O objectivo deste trabalho foi analisar o impacto do método de troca de água no nível máximo de dor referido pelos doentes submetidos a colonoscopia sem sedação, comparativamente à colonoscopia convencional com ar. Métodos: Estudo comparativo unicêntrico, prospectivo e randomizado, cego para o doente, no qual os doentes foram alocados ao grupo água, no qual se utilizou o método de troca de água, ou ao grupo ar, no qual se utilizou a insuflação de ar. Resultados: Foram randomizados 141 doentes, 70 no grupo água e 71 no grupo ar. O nível máximo de dor referido pelos doentes submetidos a colonoscopia sem sedação, avaliado através de uma escala numérica de dor (0-10), foi significativamente inferior no grupo água (3.39 ± 2.32), comparativamente ao grupo ar (4.94 ± 2.10), p < 0.001. A taxa de colonoscopia indolor foi significativamente superior no grupo água (12.9 vs. 1.4%, p = 0.009). Não se verificam diferenças significativas entre os dois grupos relativamente à indicação do exame, qualidade da preparação intestinal, tempo de entubação cecal, tempo de retirada, número de mudanças de posição, taxa de detecção de adenomas, assim como complicações no pós-procedimento. Apenas o número de compressões abdominais foi significativamente diferente, verificando-se que o método de troca de água reduziu o número necessário durante a colonoscopia. Conclusões: O método de troca de água é seguro e constitui uma alternativa igualmente eficaz à colonoscopia convencional sem sedação, associando-se a uma menor dor durante o procedimento, sem comprometer as medidas de desempenho na colonoscopia.

Eosinophilic enterocolitis is an exceptionally rare condition with few described cases in the literature, representing the least frequent manifestation of the wide spectrum of eosinophilic gastrointestinal disorders. We describe a case of a young male patient presenting with a panmural form of the disease, manifested by abdominal pain, distention, and watery diarrhea with 4 days of evolution, bowel wall thickening, and ascites. Eosinophilic ascites is probably the most unusual presentation form of this entity. It poses a diagnostic challenge because of its nonspecific symptoms, associated with the absence of standardized histological criteria, hence requiring a high level of suspicion. There is also no consensus regarding treatment: it should be individualized according to the patient’s age and severity of symptoms. A enterocolite eosinofílica constitui uma condição extremamente rara, com poucos casos descritos na literatura, representando a manifestação menos frequente do amplo espectro dos distúrbios eosinofílicos gastrointestinais. Descrevemos o caso de um jovem que apresenta uma forma transmural da doença, manifestada por dor e distensão abdominal, diarreia aquosa com quatro dias de evolução, espessamento da parede intestinal e ascite. A ascite eosinofílica é provavelmente a forma de apresentação mais rara desta entidade. Constitui um desafio diagnóstico devido à sintomatologia inespecífica, associada à ausência de critérios histológicos de diagnóstico bem estabelecidos. Não existe igualmente um consenso relativamente à sua abordagem terapêutica, devendo ser individualizada de acordo com a idade do doente e a gravidade dos sintomas.

A Fabry-Perot air bubble microcavity fabricated between a section of single mode fiber and a multimode fiber that requires only the use of a commercial fusion splicer is proposed. The study of the microcavities growth with the number of applied arcs is performed and several sensors are tested. The sensors are tested for lateral load measurements, and it is observed that there is dependence between the sensor dimensions and its sensitivity. The maximum sensitivity of 2.11 nm/N was obtained for the 161-μm-long cavity. Moreover, given the low temperature sensitivity (

In this work, we investigate the influence of some growth parameters such as high microwave power ranging from 3.0 to 4.0 kW and N2 additive on the incorporation of bonded hydrogen defects in nanocrystalline diamond (NCD) films grown through a small amount of pure N2 addition into conventional 4% CH4/H2 plasma using a 5 kW microwave plasma CVD system. Incorporation form and content of hydrogen point defects in the NCD films produced with pure N2 addition was analyzed by employing Fourier-transform infrared (FTIR) spectroscopy for the first time. A large amount of hydrogen related defects was detected in all the produced NCD films with N2 additive ranging from 29 to 87 µm thick with grain size from 47 nm to 31 nm. Furthermore, a specific new H related sharp absorption peak appears in all the NCD films grown with pure N2/CH4/H2 plasma at high powers and becomes stronger at powers higher than 3.0 kW and is even stronger than the 2920 cm−1 peak, which is commonly found in CVD diamond films. Based on these experimental findings, the role of high power and pure nitrogen addition on the growth of NCD films including hydrogen defect formation is analyzed and discussed.

This chapter focuses on new compositions of thermoplastic matrices and reinforcements to process by fused deposition modelling (FDM). The available materials for this additive manufacturing (AM) technique are generally limited to PLA—polylactic acid, ABS—acrylonitrile butadiene styrene and PA—polyamide (NYLON®) with temperature gradients and mechanical behaviours that are not suited for high-performance applications, such as aeronautics and automotive sector. In this work, an intensive research was made in order to evaluate mechanical, thermal and rheological properties considered important for 3D printing of commercial filaments. Results aided in the selection of high-performance reinforced materials for AM. Advanced polymers, such as PEEK—polyether ether ketone and PA66—polyamide 66, were the matrices chosen to produce high service nanocomposite formulations, each with varying amounts of multi-wall carbon nanotubes (MWCNTs). The resulting feedstock materials were characterized using the same techniques as the commercial filaments. Preliminary tests with printed parts of these composites were made in pursuance of their optimal printing parameters to undergo an experimental hybrid system (EHS).

Composites are finding increased use in structural high demanding and high added value applications in advanced industries. A wide diversity exists in terms of matrix type, which can be either polymeric or metallic and type of reinforcements (ceramic, polymeric or metallic). Several technologies have been used to produce these composites; among them, additive manufacturing (AM) is currently being applied. In structural applications, the presence of defects due to fabrication is of major concern, since it affects the performance of a component with negative impact, which can affect, ultimately, human lives. Thus, the detection of defects is highly important, not only surface defects but also barely visible defects. This chapter describes the main types of defects expected in composites produced by AM. The fundamentals of different non-destructive testing (NDT) techniques are briefly discussed, as well as the state of the art of numerical simulation for several NDT techniques. A multiparametric and customized inspection system was developed based on the combination of innovative techniques in modelling and testing. Experimental validation with eddy currents, ultrasounds, X-ray and thermography is presented and analysed, as well as integration of distinctive techniques and 3D scanning characterization.

[EN] FBG in polymer optical fibers (POFs) is a promising technology for a wide range of sensing applications due to a lower Young¿s modulus and a large range of applying strain. Furthermore, POFs have several properties which make them attractive for biosensing applications such as nonbrittle nature, flexibility in bending and biocompatibility. Chirped Fiber Bragg gratings (CFBGs), which are characterized by a nonuniform modulation of the refractive index show a broad reflection spectrum, enabling shortlength distributed sensing. The combining benefits of POF and CFBGs is attractive for biomedical applications. Here, we present a novel method to obtain CFBG in POF with a postprocess uniform POF FBG by using resin., The Spanish Ministerio de Ciencia, Innovación y Universidades RTI2018­101658­B­I00 FOCAL Project; National Natural Science Foundation of China (61435006, 61525502); The Science and Technology Planning Project of Guangdong Province (2017B010123005, 2018B010114002); Local Innovation and Research Teams Project of Guangdong Pearl River Talents Program (2017BT01X121). This work was developed within the scope of the project i3N, UIDB/50025/2020 & UIDP/50025/2020, financed by national funds through the FCT/MEC. Luís Pereira and Tiago Paixão acknowledge FCT for the grants SFRH/BD/146295/2019 and PD/BD/128265/2016, respectively. This work is also funded by national funds (OE), through FCT¿I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree­Law 57/2016, of August 29, changed by Law 57/2017, of July 19.

We present the first Bragg gratings fabricated in two, three and five rings undoped PMMA microstructured polymer optical fibres (mPOFs) with relative low cost 266 nm Nd:YAG laser in the 850 nm region. The fibers were connectorised with commercial ferrules for easy coupling with silica patch cables. Temperature, humidity and strain sensitivities are measured and also the impact of ring structure and the diameter of POF on the characterization measurements are studied for potential applications. We also analyzed the effect of the number of hexagonal rings structure in gratings fabrication, noticing that larger number of rings lead to more difficulties to obtain strong gratings, where we consider this performance due to the scattering effects. We demonstrate Bragg gratings fabrication in 5-rings structure mPOF after 6 min by using 266 nm Nd:YAG laser whereas no Bragg gratings have been fabricated so far using 325 nm He-Cd laser system. Up to 30 dB relative reflected power gratings are obtained in two rings mPOF, showing good time stability and promising results for undoped mPOF applications.

In this work, an inline sensor based on a double antiresonant hollow core fiber is proposed for the simultaneous measurement of refractive index and temperature. The fiber, consisting of four silica capillaries with wall thickness of ~1.5 um and a cladding with a thickness of ~36.5 um, is spliced between two sections of single mode fiber. The spectral behavior, measured in transmission, results from the combination of different frequencies which enable the discrimination between the two parameters. The sensing head is subjected to refractive index measurements using aqueous solutions with different concentrations of ethanol. For a sensor with a length of ~10 mm, and considering the lower frequency signal, the sensitivity to refractive index is 389.6 nm/RIU, whereas for the higher frequency, the sensitivity attained is 2.8 nm/RIU. On the other hand, the sensing head presented a sensitivity to temperature of 25.5 pm/K and -27.6 pm/K for the higher and lower frequencies, respectively. published

Inappropriate processing and disposal of electronic waste contributes to the contamination of aquatic systems by various types of pollutants such as the rare-earth elements (REE) in which lanthanum (La) is included. Knowledge on the toxicity of these elements in marine organisms is still scarce when compared to other metals such as mercury (Hg) and arsenic (As). Therefore, this study aims to assess the toxicity of La on the mussel Mytilus galloprovincialis, considered a good bioindicator of aquatic pollution, through the analysis of metabolic, oxidative stress, neurotoxicity and histopathological markers. Organisms were exposed to different concentrations of La for a period of 28 days (0, 0.1, 1, 10 mg/L) under controlled temperature (18 °C ± 1.0) and salinity (30 ± 1) conditions. La concentrations in mussels increased in higher exposure concentrations. La exposure demonstrated a biochemical response in mussels, evidenced by lowered metabolism and accumulation of energy reserves, activation of the antioxidant defences SOD and GPx as well as the biotransformation enzymes GSTs, especially at intermediate concentrations. Despite oxidative stress being shown by a decrease in GSH/GSSG, oxidative damage was avoided as evidenced by lower LPO and PC levels. Inhibition of the enzyme AChE demonstrated the neurotoxicity of La in this species. Histopathological indices were significantly different from the control group, indicating impacts in gonads, gills and digestive glands of mussels due to La. These results show that La can be considered a risk for marine organisms and thus its discharge into the environment should be monitored.

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. published

10 pages, 6 figures, 2 tables, Mussels, such as the marine bivalve Mytilus galloprovincialis are sentinels for marine pollution but they are also excellent bioindicators under laboratory conditions. For that, in this study we tested the modulation of biochemical responses under realistic concentrations of the toxic metal Lead (Pb) in water for 28 days under different conditions of salinity and temperature, including control condition (temperature 17 ± 1.0 °C and salinity 30 ± 1.0) as well as those within the range expected to occur due to climate change predictions (± 5 in salinity and + 4 °C in temperature). A comprehensive set of biomarkers was applied to search on modulation of biochemical responses in terms of energy metabolism, energy reserves, oxidative stress and damage occurrence in lipids, proteins as well as neurotoxicity signs. The application of an integrative Principal Coordinates Ordination (PCO) tool was successful and demonstrated that Pb caused an increase in the detoxification activity mainly evidenced by glutathione S-transferases and that the salinities 25 and 35 were, even in un-exposed mussels, responsible for cell damage seen as increased levels of lipid peroxidation (at salinity 25) and oxidised proteins (at salinity 35), Francesca Coppola, and Rui Monteiro benefited from PhD grants (SFRH/BD/118582/2016 and SFRH/BD/108535/2015, respectively), given by the National Funds through the Portuguese Science Foundation (FCT), supported by FSE and Programa Operacional Capital Humano (POCH) e da União Europeia. Rosa Freitas and Bruno Henriques were funded by national funds (OE), through FCT – Fundação para a Ciência e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. This work was also financially supported by the project BISPECIAl: BIvalveS under Polluted Environment and ClImate chAnge PTDC/CTA-AMB/28425/2017 (POCI-01-0145-FEDER-028425) funded by FEDER, through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI), and by national funds (OE), through FCT/MCTES. Thanks are due for the financial support to CESAM (UID/AMB/50017/2019), to FCT/MEC through national funds, and the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020. The Spanish Ministry of Economy, Industry and Competitivity: AimCost project (ref CGL2016-76332-R MINECO/FEDER/UE). Rosa Freitas and Montserrat Solé are members of the RED Iberoamericana RIESCOS (419RT0578) funded by CYTED

A hybrid sensor based on microstructured hollow core fiber is proposed for the simultaneous measurement of strain and temperature. The fiber, consisting of four silica capillaries with wall thickness of ~1 μm and a cladding with a thickness of ~26 μm, is spliced between two sections of single mode fiber. Using a low arc discharge power to splice the two fibers, a Fabry-Perot interferometer is formed. In this situation, light travels in the hollow core and the behavior of a twowave interferometer is observed. However, when the power of the arc discharge is increased, the structure near the splice area changes, generating new interferometric paths and giving rise to a different spectral response. In this work, sensors with a single degenerated area are analyzed. In such case, both Fabry-Perot and Michelson interferometers are created and different sensitivities to strain and temperature are obtained. The different spectral frequencies are analyzed, enabling the discrimination between the two parameters. For a sensor with a length of ~385 μm, strain sensitivities of 2.46 pm/μe and -0.52 pm/μe are obtained for the Fabry-Perot and for the Michelson interferometer, respectively. Regarding temperature, a sensitivity of 1.81 pm/°C was attained for the former, whereas for the last the sensitivity was of 42.23 pm/°C. Keywords: Hyb

Increasing emissions of Platinum-Group Elements (PGE) into marine environments may negatively impact ecosystems services and organisms wellbeing. Removing PGE from contaminated systems using efficient and low-cost technologies can therefore provide a sustainable solution to aquatic systems remediation. Previous studies highlight algae’s high binding ability to metals in solution. Assessing the viability of various algae species to remove PGE from contaminated solutions, while identifying differences in performance among algae and among elements, was the purpose of this study. For this, six macroalgae species (Ulva lactuca, Ulva intestinalis, Fucus spiralis, Fucus vesiculosus, Osmundea pinnatifida and Gracilaria sp., 3 g L−1) were exposed to PGE (Palladium, Rhodium, Ruthenium, Iridium and Platinum)-spiked seawater (10 and 500 µg L−1) for 72 h. Removal rates varied with time and among macroalgae and elements. Palladium was easily removed by all species (up to 83 %), while other PGE showed lower affinity to macroalgae. Removal sequence was Pd > Rh > Ru > Ir > Pt. Initial concentration rise induced faster and higher removal. U. lactuca performed best for all elements, while brown macroalgae were the less effective. Macroalgae external area and chemical composition were considered major factors influencing sorption, although each element and macroalgae should be examined individually. Results evidence living macroalgae (particularly U. lactuca) as a promising alternative to remediate PGE contaminated waters.

Undifferentiated carcinoma with osteoclast-like cells is a rare pancreatic neoplasm with unique ultrasound endoscopic features. A 59-year-old female presented with a 3-month history of weight loss. Abdominal computed tomography and endoscopic ultrasound showed a large pancreatic tumor with a heterogeneous echotexture and liver metastasis. Endoscopic ultrasound fine needle aspiration was used to establish the diagnosis. In this case report, we review the endoscopic, clinical, and pathological features of this type of tumor and describe for the first time the endoscopic features of real-time elastography and contrast enhancement. Real-time elastography revealed a heterogeneous predominantly blue pattern suggestive of pancreatic malignancy, and the contrast-enhanced endosonography showed a hypervascular mass and distinctive vascular (solid) and avascular (liquid/necrotic) components of the lesion, guiding the fine needle aspiration.O carcinoma indiferenciado de células do tipo osteoclástico é uma neoplasia rara com achados únicos de ultrassonografia endoscópica. Mulher, de 59 anos de idade, com história de perda ponderal nos últimos 3 meses. A tomografia computorizada e a ultrassonografia endoscópica mostraram um volumoso tumor pancreático com uma ecotextura heterogénea e metástases hepáticas. A punção aspirativa com agulha fina por ultrassonografia endoscópica estabeleceu o diagnóstico. Este caso clínico fará uma revisão dos achados endoscópicos, clínicos e histológicos deste tipo de tumor e descrever pela primeira vez os achados endoscópicos da elastografia em tempo real e do contraste por ultrassonografia. A elastografia em tempo real revelou um padrão heterogéneo predominante azul, sugestivo de malignidade pancreática e o contraste por ultrassonografia mostrou uma massa hipervascular, diferenciando o componente vascular (sólido) do não vascular (tecido necrótico/líquido) da lesão, orientando a punção com agulha fina.

In this work it is evaluated the possibility of central blood pressure assessment using distension waves, obtained with a low cost optical fiber sensor, instead of regular arterial tonometry. Carotid distension and pressure waveforms were acquired in 15 young subjects. Form factors, root-mean-square error (RMSE), harmonic decomposition and central systolic pressures for both techniques were analysed. The pressure waves assessed by the piezoelectric probe had lower form factors than the ones assessed by the optical fiber sensor, due to the different nature of the waves (51.05 ± 5.15% versus 40.53 ± 5.70%), translating in a RMSE of 14 ± 2%. Regarding the harmonic analysis, paired t -tests shown that the first four harmonics are not significant different (p ⩽ 0.05), and Pearson correlation studies retrieve that the 2nd–7th harmonics are correlated (p ⩽ 0.03). Central systolic pressures were also obtained with both techniques displaying a very strong Pearson correlation (0.99) and a small difference of 0.63 ± 2.40 mmHg. These pre-clinical results support a future clinical validation study in larger and broader cohorts.