Optical Strain Gauge Prototype Based on a High Sensitivity Balloon-like Interferometer and Additive Manufacturing.

An optical strain gauge based on a balloon-like interferometer structure formed by a bent standard single-mode fiber combined with a 3D printer piece has been presented and demonstrated, which can be used to measure displacement. The interferometer has a simple and compact size, easy fabrication, low cost, and is repeatable. The sensor is based on the interference between the core and cladding modes. This is caused by the fiber's curvature because when light propagates through the curved balloon-shaped interferometer region, a portion of it will be released from the core limitation and coupled to the cladding. The balloon has an axial displacement as a result of how the artwork was constructed. The sensor head is sandwiched between two cantilevers such that when there is a displacement, the dimension associated with the micro bend is altered. The sensor response as a function of displacement can be determined using wavelength shift or intensity change interrogation techniques. Therefore, this optical strain gauge is a good option for applications where structure displacement needs to be examined. The sensor presents a sensitivity of 55.014 nm for displacement measurements ranging from 0 to 10 mm and a strain sensitivity of 500.13 pm/µÏµ.

A Simple Optical Sensor Based on Multimodal Interference Superimposed on Additive Manufacturing for Diameter Measurement.

In many areas, the analysis of a cylindrical structure is necessary, and a form to analyze it is by evaluating the diameter changes. Some areas can be cited: pipelines for oil or gas distribution and radial growth of trees whose diameter changes are directly related to irrigation and the radial expansion since it depends on the water soil deficit. For some species, these radial variations can change in around 5 mm. This paper proposes and experimentally investigates a sensor based on a core diameter mismatch technique for diameter changes measurement. The sensor structure is a combination of a cylindrical piece developed using a 3D printer and a Mach-Zehnder interferometer. The pieces were developed to assist in monitoring the diameter variation. It is formed by splicing an uncoated short section of MMF (Multimode Fiber) between two standard SMFs (Singlemode Fibers) called SMF-MMF-SMF (SMS), where the MMF length is 15 mm. The work is divided into two main parts. Firstly, the sensor was fixed at two points on the first developed piece, and the diameter reduction caused dips or peaks shift of the transmittance spectrum due to curvature and strain influence. The fixation point (FP) distances used are: 5 mm, 10 mm, and 15 mm. Finally, the setup with the best sensitivity was chosen, from first results, to develop another test with an optimization. This optimization is performed in the printed piece where two supports are created so that only the strain influences the sensor. The results showed good sensitivity, reasonable dynamic range, and easy setup reproduction. Therefore, the sensor could be used for diameter variation measurement for proposed applications.

Reassessing the systematics of Leptodeira (Serpentes, Dipsadidae) with emphasis in the South American species

Within the diverse subfamily Dipsadinae, Imantodini represents one of the few groups distributed in North, Central and South America. The tribe comprises the genera Leptodeira and Imantodes, from which Leptodeira is the most diverse, including 15 species and 11 subspecies, distributed from southern USA to central Argentina. Taxonomy and affinities among these taxa are poorly resolved, and the phylogenetic relationships among the South American diversity were never properly assessed before. Here, we investigate the phylogenetic relationships and the taxonomic status of Leptodeira spp. based on a comprehensive multilocus dataset with emphasis in the South American radiation. Besides assessing the phylogenetic relationship and species cohesion, we also evaluate the morphological variation among the South American diversity of Leptodeira. Our results support the monophyly of Imatodini and Leptodeira, while indicating that several individuals classified as Leptodeira annulata and L. septentrionalis do not cluster together within their respective species. Moreover, specimens identified as belonging to the subspecies L. a. annulata, L. a. cussiliris, L. s. ornata and L. s. polysticta do not group together suggesting the current classification includes non-natural groups. The analysis of morphological evidence also supports the phylogenetics results, indicating that several clades can be recognized as evolutionary units presenting distinct phenotypes. To equate the taxonomy to our results, we propose a new taxonomic arrangement for Leptodeira in which we are: (1) redefining the composition of L. annulata and L. septentrionalis; (2) elevating five subspecies to species level; (3) revalidating one species; (4) recognizing four species complexes; and (5) indicating the presence of hidden diversity (probably four undescribed species). Finally, we describe a new species (Leptodeira tarairiu sp. nov.) from the open formations of South America (Cerrado and Caatinga), and we provide detailed redescriptions for all South American species of Leptodeira.

ERS ECM Awardee 2021, a preview of LSC 2022 and a brief overview of the Respiratory Channel.

This article presents the ERS Early Career Member Award winner 2021 (@agbasteiro), and provides a brief description of the @EuroRespSoc Lung Science Conference 2022 and the Respiratory Channel https://bit.ly/2XTylbK.

Improved dark ambient degradation of organic pollutants by cerium strontium cobalt perovskite.

This work investigates the effect of cerium substation into strontium cobalt perovskites (CeSrCoO) for the oxidative degradation of Orange II (OII) in dark ambient conditions without the aid of any external stimulants such as light, heating or chemical additives. The OII degradation rate by CeSrCoO reached 65% in the first hour, whilst for the blank sample without cerium (SrCoO) took over 2 hr to reach the same level of OII degradation. Hence, the cerium substitution improved the catalytic activity of the perovskite material, mainly associated with the Ce0.1Sr0.9CoO3 perovskite phase. Upon contacting CeSrCoO, the -NN- azo bonds of the OII molecules broke down resulting in electron donation and the formation of by-products. The electrons are injected into the CeSrCoO and resulted in a redox pair of Co3+/Co2+, establishing a bridge for the electron transfer between OII and the catalysts. Concomitantly, the electrons also formed reactive species (·OH) responsible for OII degradation as evidenced by radical trapping experiment. Reactive species were formed via the reaction between O2 and donated electrons from OII with the aid of cobalt redox pair. As the prepared materials dispensed with the need for light irradiation and additional oxidants, it opens a window of environmental applications for treating contaminated wastewaters.

Taxonomic revision of the Erythrolamprus reginae species group, with description of a new species from Guiana Shield (Serpentes: Xenodontinae).

We perform a review of the Erythrolamprus reginae species group and putative related taxa (E. dorsocorallinus, E. zweifeli, and E. oligolepis), based on external morphology and hemipenial characters. We infer species boundaries among taxa traditionally associated with this group, recognizing two nominal subspecies (Erythrolamprus reginae reginae and E. r. macrosomus) in the species level. We propose the synonymy of E. r. semilineatus with E. reginae and recognize the validity of the related taxa, such as: E. dorsocorallinus, E. zweifeli, and E. oligolepis. In addition, two specimens occurring in the state Amapá, Brazil, are herein described as a new species. Therefore, we provide an identification key for the species of the group and discuss some of the combination of morphological features useful to delimitate the species of this group, in comparison with other representatives of the genus Erythrolamprus.

2D/3D Assemblies of Amine-Functionalized Graphene Silica (Templated) Aerogel for Enhanced CO2 Sorption.

This work investigates the one-pot facile synthesis of novel 2D/3D assemblies containing graphene silica (templated) aerogel sorbents for CO2 capture, a greenhouse gas of major global concern. In this synthesis, 3D silica (templated) aerogels were formed along the planes of 2D graphene sheets, resulting in 2D/3D assemblies of flake-like shapes. The templates were burnt off from the 2D/3D assembly, leaving a mesoporous cavity which increased with the carbon chain length used in the synthesis method. As such, morphological features related to surface area and total pore volume increased significantly by over 80% as compared to blank (no template) samples and reached maximum values of 734 m2 g-1 and 0.42 cm3 g-1, respectively. The increase in total pore volume allowed for higher content of impregnated amine into the 2D/3D assembly followed by a freeze-drying method. The CO2 sorption capacity of the amine-functionalized 2D/3D assemblies reached high values at 4.9 mmol g-1 (mass over weight ratio), equivalent to 11.67 mmol cm-3 (mass over total pore volume ratio). The amine-functionalized 2D/3D assemblies were stable over 10 cycles of CO2 sorption and desorption. Further, heat of sorption results were generally low, with the lowest value reaching 59 kJ mol-1. These results are desirable for the deployment of 2D/3D assemblies as sorbents to capture CO2.

Significant hyperopic shift in a patient with extreme myopia following severe hypotonia caused by glaucoma filtering surgery.

INTRODUCTION:: To report the case of a high hyperopic refractive shift associated with significant shortening of the ocular axial length following glaucoma filtering surgery. METHODS:: Case report. Patient's records were consulted retrospectively. RESULTS:: A 57-year-old woman, highly myopic, with a history of bilateral intraocular refractive surgery in 1998 (phakic lens ZB5M) and bilensectomy in 2011 (phakic intraocular lens extraction plus cataract surgery with pseudophakic intraocular lens implantation), presented with consistently high intraocular pressure. Despite the treatment with different topical antiglaucomatous medications and good compliance, her intraocular pressure values remained consistently above 20 mmHg. In 2016, the patient was submitted for glaucoma filtering surgery and the mini shunt Ex-Press was implanted in both the eyes (3 months between surgeries). On the first postoperative day, the eyes were hypotonic (intraocular pressure of 5 mmHg) and bilateral macular edema was observed. Three days later, the intraocular pressure in both the eyes reached values higher than 6 mmHg (between 6 and 14 mmHg). Five months after the surgery the macular edema resolved and a significant shortening of the axial length and an important hyperopic refractive shift was observed. When comparing the preoperative and postoperative (18 months) measurements, the variation of the axial length was 2.49 mm in the right eye and 2.19 mm in the left eye; the patient refraction (spherical equivalent) shifted 2.50 diopters in the right eye and 1.75 diopters in the left eye. CONCLUSION:: To the best of our knowledge, we report herein the first documented case of an axial length change of this magnitude after glaucoma filtering surgery.

Influence of passage number on the impact of the secretome of adipose tissue stem cells on neural survival, neurodifferentiation and axonal growth.

Mesenchymal stem cells (MSCs), and within them adipose tissue derived stem cells (ASCs), have been shown to have therapeutic effects on central nervous system (CNS) cell populations. Such effects have been mostly attributed to soluble factors, as well as vesicles, present in their secretome. Yet, little is known about the impact that MSC passaging might have in the secretion therapeutic profile. Our aim was to show how human ASCs (hASCs) passage number influences the effect of their secretome in neuronal survival, differentiation and axonal growth. For this purpose, post-natal rat hippocampal primary cultures, human neural progenitor cell (hNPCs) cultures and dorsal root ganglia (DRGs) explants were incubated with secretome, collected as conditioned media (CM), obtained from hASCs in P3, P6, P9 and P12. Results showed no differences when comparing percentages of MAP-2 positive cells (a mature neuronal marker) in neuronal cultures or hNPCs, after incubation with hASCs secretome from different passages. The same was observed regarding DRG neurite outgrowth. In order to characterize the secretomes obtained from different passages, a proteomic analysis was performed, revealing that its composition did not vary significantly with passage number P3 to P12. Results allowed us to identify several key proteins, such as pigment epithelium derived factor (PEDF), DJ-1, interleucin-6 (IL-6) and galectin, all of which have already proven to play neuroprotective and neurodifferentiating roles. Proteins that promote neurite outgrowth were also found present, such as semaphorin 7A and glypican-1. We conclude that cellular passaging does not influence significantly hASCs's secretome properties especially their ability to support post-natal neuronal survival, induce neurodifferentiation and promote axonal growth.

Enhanced CO2 sorption efficiency in amine-functionalised 2D/3D graphene/silica hybrid sorbents.

Owing to the geometrical features of 2D graphene intercalated into 3D mesoporous silica, CO2 sorption increased by 51% and the heat of sorption reduced by up to 27% as compared to a pure 3D mesoporous silica sorbent without graphene. The superior performance of the amine-functionalised 2D/3D hybrid sorbent was attributed to the enhanced porosity and graphene physisorption at the expense of amine chemisorption.

Indicators for evaluating European population health: a Delphi selection process.

BACKGROUND: Indicators are essential instruments for monitoring and evaluating population health. The selection of a multidimensional set of indicators should not only reflect the scientific evidence on health outcomes and health determinants, but also the views of health experts and stakeholders. The aim of this study is to describe the Delphi selection process designed to promote agreement on indicators considered relevant to evaluate population health at the European regional level. METHODS: Indicators were selected in a Delphi survey conducted using a web-platform designed to implement and monitor participatory processes. It involved a panel of 51 experts and 30 stakeholders from different areas of knowledge and geographies. In three consecutive rounds the panel indicated their level of agreement or disagreement with indicator's relevance for evaluating population health in Europe. Inferential statistics were applied to draw conclusions on observed level of agreement (Scott's Pi interrater reliability coefficient) and opinion change (McNemar Chi-square test). Multivariate analysis of variance was conducted to check if the field of expertise influenced the panellist responses (Wilk's Lambda test). RESULTS: The panel participated extensively in the study (overall response rate: 80%). Eighty indicators reached group agreement for selection in the areas of: economic and social environment (12); demographic change (5); lifestyle and health behaviours (8); physical environment (6); built environment (12); healthcare services (11) and health outcomes (26). Higher convergence of group opinion towards agreement on the relevance of indicators was seen for lifestyle and health behaviours, healthcare services, and health outcomes. The panellists' field of expertise influenced responses: statistically significant differences were found for economic and social environment (p < 0.05 in round 1 and 2), physical environment (p < 0.01 in round 1) and health outcomes (p < 0.01 in round 3). CONCLUSIONS: The high levels of participation observed in this study, by involving experts and stakeholders and ascertaining their views, underpinned the added value of using a transparent Web-Delphi process to promote agreement on what indicators are relevant to appraise population health.

Environmental mineralization of caffeine micro-pollutant by Fe-MFI zeolites.

Environmentally emerging micro-pollutant, caffeine, was mineralized (i.e., full degradation) by the isomorphic incorporation of Fe into silicalite-1 (mordenite framework inverted (MFI) structure zeolite) through a microwave synthesis method. The Fe incorporation conferred mesopore formation that facilitated caffeine access and transport to the MFI zeolite structure. Increasing the Fe content favored the formation of Fe(O)4 sites within the MFI structure. The catalytic activity for the degradation of caffeine increased as a function of Fe(O)4 sites via a Fenton-like heterogeneous reaction, otherwise not attainable using Fe-free pure MFI zeolites. Caffeine degradation reached 96% (TOC based) for zeolites containing 2.33% of Fe.

Mixed Matrix Carbon Molecular Sieve and Alumina (CMS-Al2O3) Membranes.

This work shows mixed matrix inorganic membranes prepared by the vacuum-assisted impregnation method, where phenolic resin precursors filled the pore of α-alumina substrates. Upon carbonisation, the phenolic resin decomposed into several fragments derived from the backbone of the resin matrix. The final stages of decomposition (>650 °C) led to a formation of carbon molecular sieve (CMS) structures, reaching the lowest average pore sizes of ~5 Å at carbonisation temperatures of 700 °C. The combination of vacuum-assisted impregnation and carbonisation led to the formation of mixed matrix of CMS and α-alumina particles (CMS-Al2O3) in a single membrane. These membranes were tested for pervaporative desalination and gave very high water fluxes of up to 25 kg m(-2) h(-1) for seawater (NaCl 3.5 wt%) at 75 °C. Salt rejection was also very high varying between 93-99% depending on temperature and feed salt concentration. Interestingly, the water fluxes remained almost constant and were not affected as feed salt concentration increased from 0.3, 1 and 3.5 wt%.

Molecular Weight Cut-Off and Structural Analysis of Vacuum-Assisted Titania Membranes for Water Processing.

This work investigates the structural formation and analyses of titania membranes (TM) prepared using different vacuum exposure times for molecular weight (MW) cut-off performance and oil/water separation. Titania membranes were synthesized via a sol-gel method and coated on macroporous alumina tubes followed by exposure to a vacuum between 30 and 1200 s and then calcined at 400 °C. X-ray diffraction and nitrogen adsorption analyses showed that the crystallite size and particle size of titania increased as a function of vacuum time. All the TM membranes were mesoporous with an average pore diameter of ~3.6 nm with an anatase crystal morphology. Water, glucose, sucrose, and polyvinylpyrrolidone with 40 and 360 kDa (PVP-40 kDa and PVP-360 kDa) were used as feed solutions for MW cut-off and hexadecane solution for oil filtration investigation. The TM membranes were not able to separate glucose and sucrose, thus indicating the membrane pore sizes are larger than the kinetic diameter of sucrose of 0.9 nm, irrespective of vacuum exposure time. They also showed only moderate rejection (20%) of the smaller PVP-40 kDa, however, all the membranes were able to obtain an excellent rejection of near 100% for the larger PVP-360 kDa molecule. Furthermore, the TM membranes were tested for the separation of oil emulsions with a high concentration of oil (3000 ppm), reaching high oil rejections of more than 90% of oil. In general, the water fluxes increased with the vacuum exposure time indicating a pore structural tailoring effect. It is therefore proposed that a mechanism of pore size tailoring was formed by an interconnected network of Ti-O-Ti nanoparticles with inter-particle voids, which increased as TiO2 nanoparticle size increased as a function of vacuum exposure time, and thus reduced the water transport resistance through the TM membranes.

Ternary Phase-Separation Investigation of Sol-Gel Derived Silica from Ethyl Silicate 40.

A ternary phase-separation investigation of the ethyl silicate 40 (ES40) sol-gel process was conducted using ethanol and water as the solvent and hydrolysing agent, respectively. This oligomeric silica precursor underwent various degrees of phase separation behaviour in solution during the sol-gel reactions as a function of temperature and H2O/Si ratios. The solution composition within the immiscible region of the ES40 phase-separated system shows that the hydrolysis and condensation reactions decreased with decreasing reaction temperature. A mesoporous structure was obtained at low temperature due to weak drying forces from slow solvent evaporation on one hand and formation of unreacted ES40 cages in the other, which reduced network shrinkage and produced larger pores. This was attributed to the concentration of the reactive sites around the phase-separated interface, which enhanced the condensation and crosslinking. Contrary to dense silica structures obtained from sol-gel reactions in the miscible region, higher microporosity was produced via a phase-separated sol-gel system by using high H2O/Si ratios. This tailoring process facilitated further condensation reactions and crosslinking of silica chains, which coupled with stiffening of the network, made it more resistant to compression and densification.

Hydrothermal stability investigation of micro- and mesoporous silica containing long-range ordered cobalt oxide clusters by XAS.

This work investigates the hydrothermal stability of cobalt doped silica materials with different Co/Si molar ratios (0, 0.05, 0.10, and 0.25). The resultant materials were characterized by N2 sorption and chemical structures by Raman and X-ray absorption spectroscopy before and after a harsh hydrothermal exposure (550 °C, 75 mol% vapour and 40 h). The cobalt silica materials showed a lower surface area loss from 48% to 12% with increasing Co/Si molar ratio from 0.05 to 0.25 and relatively maintaining their pore size distribution, while pure silica exhibited significant surface area reduction (80%) and pore size broadening. For low cobalt loading sample (Co/Si = 0.05), the cobalt was highly dispersed in the silica network in a tetrahedral coordination with oxygen and a small proportion of Co-Co interaction in the second shell. Long range order Co3O4 was observed when Co/Si molar ratio increased to 0.10 and 0.25. The hydrothermal exposure did not affect the local cobalt environments and no cobalt-silicon interaction was observed by X-ray absorption spectroscopy. The hydrothermal stability of the silica matrix was attributed to the physical barrier of cobalt oxide in opposing densification and silica mobility under harsh hydrothermal conditions.

The sacrificial role of graphene oxide in stabilising a Fenton-like catalyst GO-Fe3O4.

Owing to the electron donor-acceptor properties of GO, the active sites ([triple bond, length as m-dash]Fe(2+)) of Fe3O4 are not oxidised ([triple bond, length as m-dash]Fe(3+)) in the heterogeneous Fenton-like reaction. GO plays a sacrificial role via the oxidation of (C[double bond, length as m-dash]C) carbon domains, and transferring electrons to Fe3O4. Therefore, GO-Fe3O4 confers superior catalytic efficiency, recyclability and longevity, otherwise not available in Fe3O4.

Nanoscale assembly of lanthanum silica with dense and porous interfacial structures.

This work reports on the nanoscale assembly of hybrid lanthanum oxide and silica structures, which form patterns of interfacial dense and porous networks. It was found that increasing the molar ratio of lanthanum nitrate to tetraethyl orthosilicate (TEOS) in an acid catalysed sol-gel process alters the expected microporous metal oxide silica structure to a predominantly mesoporous structure above a critical lanthanum concentration. This change manifests itself by the formation of a lanthanum silicate phase, which results from the reaction of lanthanum oxide nanoparticles with the silica matrix. This process converts the microporous silica into the denser silicate phase. Above a lanthanum to silica ratio of 0.15, the combination of growth and microporous silica consumption results in the formation of nanoscale hybrid lanthanum oxides, with the inter-nano-domain spacing forming mesoporous volume. As the size of these nano-domains increases with concentration, so does the mesoporous volume. The absence of lanthanum hydroxide (La(OH)3) suggests the formation of La2O3 surrounded by lanthanum silicate.

Modulation of microporous/mesoporous structures in self-templated cobalt-silica.

Finite control of pore size distributions is a highly desired attribute when producing porous materials. While many methodologies strive to produce such materials through one-pot strategies, oftentimes the pore structure requires post-treatment modification. In this study, modulation of pore size in cobalt-silica systems was investigated by a novel, non-destructive, self-templated method. These systems were produced from two cobalt-containing silica starting materials which differed by extent of condensation. These starting materials, sol (SG') and xerogel (XG'), were mixed with pure silica sol to produce materials containing 5-40 mol% Co. The resultant SG-series materials exhibited typical attributes for cobalt-silica systems: mesoporous characteristics developed at high cobalt concentrations, coinciding with Co3O4 formation; whereas, in the XG-series materials, these mesoporous characteristics were extensively suppressed. Based on an examination of the resultant materials a mechanism describing the pore size formation and modulation of the two systems was proposed. Pore size modulation in the XG-series was caused, in part, by the cobalt source acting as an autogenous template for the condensation of the silica network. These domains could be modified when wetted, allowing for the infiltration and subsequent condensation of silica oligomers into the pre-formed, mesoporous cages, leading to a reduction in the mesoporous content of the final product.

A pervaporation study of ammonia solutions using molecular sieve silica membranes.

An innovative concept is proposed to recover ammonia from industrial wastewater using a molecular sieve silica membrane in pervaporation (PV), benchmarked against vacuum membrane distillation (VMD). Cobalt and iron doped molecular sieve silica-based ceramic membranes were evaluated based on the ammonia concentration factor downstream and long-term performance. A modified low-temperature membrane evaluation system was utilized, featuring the ability to capture and measure ammonia in the permeate. It was found that the silica membrane with confirmed molecular sieving features had higher water selectivity over ammonia. This was due to a size selectivity mechanism that favoured water, but blocked ammonia. However, a cobalt doped silica membrane previously treated with high temperature water solutions demonstrated extraordinary preference towards ammonia by achieving up to a 50,000 mg/L ammonia concentration (a reusable concentration level) measured in the permeate when fed with 800 mg/L of ammonia solution. This exceeded the concentration factor expected by the benchmark VMD process by four-fold, suspected to be due to the competitive adsorption of ammonia over water into the silica structure with pores now large enough to accommodate ammonia. However, this membrane showed a gradual decline in selectivity, suspected to be due to the degradation of the silica material/pore structure after several hours of operation.