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Percutaneous ethanol ablation has emerged as a treatment for recurrent papillary thyroid carcinoma in the lateral neck after compartment-oriented therapeutic lymphadenectomy. However, the safety and utility of percutaneous ethanol ablation as a primary treatment modality for lateral neck metastases remains undefined. We aimed to investigate long-term outcomes of percutaneous ethanol ablation of lateral neck papillary thyroid carcinoma recurrence both with and without prior lymphadenectomy. We conducted a retrospective study of patients with lateral neck papillary thyroid carcinoma treated with percutaneous ethanol ablation from 2013 to 2018. Patient characteristics, disease volume, morbidity, and recurrence (development of new lymphadenopathy within a percutaneous ethanol ablation-treated nodal compartment) were assessed. We identified 117 patients who underwent percutaneous ethanol ablation for papillary thyroid carcinoma lateral neck metastases—67 (57%) had a prior lateral neck dissection. Median follow-up after percutaneous ethanol ablation was 5.5 years (interquartile range 3.1–7.5). On average, 1.4 lymph nodes (range: 1–6) were treated. Three patients (3%) developed transient nerve-related complications after percutaneous ethanol ablation. Of 15 patients who underwent lateral neck dissection after percutaneous ethanol ablation (including patients undergoing repeat lateral neck dissection), dissection was "difficult" in 8 (53%) (7 of whom had previously undergone lateral neck dissection), and 4 (27%) developed complications (transient nerve dysfunction = 3, lymphatic leak = 1). Thirty-three patients (28%) developed recurrent papillary thyroid carcinoma. No difference in recurrence was seen between patients who did or did not undergo pre-percutaneous ethanol ablation lateral neck dissection (no pre-percutaneous ethanol ablation lateral neck dissection: 24%, pre-percutaneous ethanol ablation lateral neck dissection, 31%; hazard ratio = 1.27, 95% confidence interval 0.62–2.58; P =.514). Percutaneous ethanol ablation may be a safe primary treatment modality for papillary thyroid carcinoma lateral neck nodal recurrence in selected patients with low-volume nodal disease. [ABSTRACT FROM AUTHOR]

Society has become increasingly dependent on telecommunication, which has been shown to negatively impact vocal function. This study explores the use of sidetone regulation during audio-visual communication as one potential technique to alleviate the effects of telecommunication on the voice. The speech acoustics of 18 participants with typical voices were measured during conversational tasks during three conditions of sidetone amplification: baseline (no sidetone amplification), low sidetone amplification, and high sidetone amplification. Vocal intensity, vocal quality (estimated using acoustic measures of the low-high ratio and the smoothed cepstral peak prominence), and self-perceived vocal effort were used to measure the impacts of sidetone amplification on vocal function. Compared to baseline, there were statistically significant decreases in vocal intensity and increases in low-high ratio in the high level of sidetone amplification condition. Changes in these measures were not significantly correlated. When asked to rank conditions based on their perceived vocal effort, participants most often ranked the high level of sidetone amplification as least effortful; however, the visual-analog ratings of vocal effort were not significantly different between conditions. The smoothed cepstral peak prominence did not change with varying levels of sidetone amplification. Vocal intensity decreased with high levels of sidetone amplification. High levels of sidetone amplification also resulted in increases in the low-high ratio, which were shown to be more than just a byproduct of decreased vocal intensity. The impact of sidetone amplification on vocal effort was less clear, but results suggested that participants generally decreased their vocal effort with increased levels of sidetone amplification. This was a preliminary study and future work is warranted in a population of participants with voice complaints and in a more noisy, realistic environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • Stacked cells in parallel configuration performs better than in series. • Increased electrode size cell performs better than stacking cells. • Successful scale up by a factor of 4 in the Caro's acid electrochemical production. • Successful resizing (enlarging) of a very efficient electrochemical prototype cell. • Important effect of scavengers suggested by a simple phenomenological model. This work focuses on very important aspects associated with the scale up of electrochemical devices by facing a 4-times increase in the electrochemical production of the Caro's acid, starting from a very efficient electrochemical cell that was developed and evaluated in previous works for this process. Thus, the effect is compared of (a) increasing the size of the electrodes by four by resizing, adapting, and manufacturing the cell prototype using 3-D printing technology and (b) that of stacking four cells to reach the same surface area, using different hydraulic connection configurations. Results demonstrate that the resizing of the electrochemical cell is more successful than stacking four cells. Resizing allows to obtain not only results that are comparable to those obtained by the lower scale cell but even to improve those results, because of the lower impact of edge effects. Regarding hydraulic connection, it was found that it is better to use parallel than series configuration. A simple phenomenological model is used to conclude that scavenging effects are higher when the series configuration is used. The resized cell was fully evaluated from the fluid dynamic behavior, pointing out its outstanding behavior. [ABSTRACT FROM AUTHOR]

Copyright of Revista Española de Cardiología (18855857) is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue Francaise d'Allergologie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Española de Cardiología (18855857) is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report a synthetic strategy to combine different moieties in a single structure using cyanuric chloride (2,4,6-trichlorotriazine) as a starting platform for preparing potential bioimaging agents. This reacted with macrocycles of the porphyrin family and DOTA type metal chelators through mono-, di- and tri- substitution of its chlorine atoms by appropriate nucleophiles, controlling the stepwise by temperature, to produce a system that opens the potential for biomedicinal applications. Porphyrins were chosen as one of the sensing arms, based on their rich structural chemistry, and excellent photophysical properties, while DO3A was used since it can form a versatile aminopropionate functionalized metal ion chelator. All new compounds were fully characterized, both spectroscopically and photophysically. [ABSTRACT FROM AUTHOR]

It is well understood that hearing plays an important role in accurate vocal production. Singers in particular rely on auditory cues and auditory feedback to reproduce specific pitch contours. Therefore, even mild hearing loss may have a detrimental effect on a singer's ability to perform. This study investigates the effect of hearing loss on self-reported vocal production in singers, specifically in the domains of pitch matching, pitch maintenance, vowel production, and dynamic control as well as the effect of hearing loss on vocal handicap. An 18-item electronic self-report survey was distributed to the members of the National Association of Teachers of Singing and to the Voice Foundation. Data collected included demographics, the Singing Voice Handicap Index-10 (SVHI-10), and a series of closed and open-ended questions. Demographic variables, variables related to the SVHI-10, and variables related to the newly introduced survey were included in a hierarchical regression analysis to determine significant relationships. Among 206 eligible participants, 37 individuals reported a voice problem, 58 reported hearing loss, and 19 reported concurrent hearing loss and a voice problem. Among males, there were no significant differences between hearing impaired and normal hearing singers in reported pitch matching, pitch maintenance, dynamic control, and vowel matching when those with voice problems were excluded and included. However, in females, when singers with voice problems were excluded, there was a significant difference between hearing impaired and normal hearing singers in pitch matching (P = 0.38). Additionally, when singers with voice problems were included in the female subset, significant differences emerged between the hearing impaired and normal hearing singers in areas of pitch matching (P = 0.01) and vowel matching (P = 0.02). Further, controlling for gender, when excluding voice problems, there was a significant difference between the SVHI-10 scores of normal hearing (mean = 9.03) and hearing impaired participants (mean = 11.30, P = 0.02). This difference continued to be significant when including those with voice problems (normal hearing mean = 9.97, hearing impaired mean=14.1, P <0.0001). Additionally, individuals with hearing impairments were more likely to report higher perceived vocal handicap scores as reflected on the SVHI-10 than normal hearing respondents (P = 0.002). Other factors associated with higher likelihood of SVHI-10 score include older age (P = 0.008), having a voice problem (P <0.0001), and being paid to sing within the past six months (P = 0.001). When controlling for voice problems, singers with hearing impairments subjectively did not perceive that they performed less accurately on pitch matching, pitch maintenance, dynamic control, and vowel matching, yet they scored higher on the SVHI-10 indicating vocal handicap. Further study is needed to characterize the relationship between perceived and measured vocal accuracy in singers with hearing loss. [ABSTRACT FROM AUTHOR]

A geochemical survey of the Las Tres Vírgenes geothermal field (LTVGF), Baja California Sur, Mexico, was carried out to determine the origin and evolution of its fluids, along with the influence of injection of local brines, and inhibitors intended to manage carbonate scaling issues. Major and minor cations, Cl, Br, Sr, O, H, and noble gas (He, Ne, Ar, Kr and Xe) isotopes were measured in fluids collected from four production wells, two injection wells, and one fumarole (El Azufre) in 2016 and 2018. Variations in the stable isotopes of water (δD and δ18O) and halogens (δ37Cl, δ81Br) over the years suggest that local brine reinjection might have started to modify the pristine chemistry of the fluids. However, relevant information on the original geothermal fluids has been preserved. The Na/Br and Cl/Br ratios suggest that LTVGF brines are seawater having leached evaporite deposits (halite). These deposits are absent in the area, but were likely present during the Miocene, prior to the breakup of the Gulf of California, suggesting that the saline fluid end-member at the LTVGF could be several million years old. Measured 3He/4He ratios (R) normalized to the atmospheric ratio Ra (= 1.384 × 10−6) plotted against the 4He/20Ne ratios suggest mixing between a mantle fluid with a R/Ra of 6.19, typical of the sub-continental lithospheric mantle and an atmospheric helium component. The R/Ra versus the 132Xe/36Ar ratio normalized to air suggests mixing between a mantle-rich pre-production fluid and air. The source of air appears to be linked to local gravity-controlled flow reinjection which causes the entrapment of air bubbles, leading to a fluid supersaturated in atmospheric noble gases. This pattern suggests that reinjection fluids are impacting the production area. • Las Tres Vírgenes is the smallest geothermal field in operation in Mexico. • Development is sought but require understanding the present evolution of fluids. • Noble gas isotopic and elemental ratios show air enrichments specific to each well. • These enrichments could indicate that injection is reaching the production zone. [ABSTRACT FROM AUTHOR]

Abstract Results of a survey of noble gases, water stable isotopes (δD and δ18O), and chlorine (Cl) and bromine (Br) contents measured in geothermal waters from the high-enthalpy, liquid-dominated Cerro Prieto Geothermal Field (CPGF) are reported. Helium isotopic ratios (3He/4He) help to identify two distinct fluids: a magmatic fluid, with 3He/4He (R) ratios of up to 7.3 times that of the atmospheric ratio (Ra = 1.384 × 10−6), and a 4He-rich fluid, with 3He/4He ≤ 3.5 Ra. The helium isotopic systematics point to limited modern freshwater recharge in the CPGF, and thus to the presence of a nearly fossil geothermal system. U-Th/4He-estimated minimum residence times for the 4He-rich fluid component vary from 1.5 to 1.8 Ma, corresponding to the age of the Colorado River paleo-delta sediments, suggesting the presence of connate waters. Cl and Br concentrations indicate that this connate water component is seawater with minor halite dissolution. Together with Cl and Br, the isotopic signature of the water (δD, δ18O) indicates the presence of a third old fluid of meteoric origin, from Late Quaternary to Holocene, corresponding to recharge during colder and wetter periods than today. This is identified as being old groundwater from the Colorado Delta unconsolidated sediments, which cap the Cerro Prieto reservoir. Our results suggest little direct recharge to the CPGF. The spatial distribution of helium isotopes in the reservoir shows that connate waters dominate the central portion of the field and mix with the magmatic fluid containing mantle He, with both fluids rising at the center of the basin where the heat source is located. Deep magmatic fluids containing mantle helium enter laterally into the reservoir, through the main lateral strike-slip faults (i.e., the Cerro Prieto and Imperial faults). Graphical abstract 4He/20Ne versus 3He/4He ratios (R/Ra) showing that Cerro Prieto fluids are mixtures of connate waters and magmatic fluids, with little modern recharge. Unlabelled Image Highlights • Extensive noble gas survey was carried out in the Cerro Prieto Geothermal Field. • 3He/4He indicates magmatic and old sedimentary fluids, with little recharge. • Cl, Br, and U-Th/He fluid ages suggest that old fluids are connate seawater. • Stable isotopes and halogens indicate a third old groundwater from shallower aquifers. • Active modern recharge is limited, indicating Cerro Prieto is a fossil geothermal system. [ABSTRACT FROM AUTHOR]

Abstract Poly(ether ether ketone) (PEEK) is a relevant thermoplastic in industry and in the biomedical sector. In this work, the lubricant capability of graphene nanoplatelets (GNPs) is used for improving the PEEK wear properties. Nanocomposites were prepared by solvent-free melt-blending and injection molding at various compositions between 1 and 10 wt. % of GNPs. The Raman G band shows a progressive increment proportional to the bulk GNP percentage. From calorimetric data, the polymer matrix structure is interpreted in terms of a 3-phase model, in which the crystalline phase fluctuates from 39 to 34% upon GNP addition. Thermal conductivity varies in accordance with the polymer crystallinity. Tensile and flexural tests show a progressive increase in the modulus, as well as a decrease in the fracture strength and the work of fracture. Most important, the composite surface undergoes a substantial improvement in hardness (60%), together with a decrease in the coefficient of friction (−38%) and a great reduction in the wear factor (−83%). Abrasion and fatigue wear mechanisms are predominant at the lowest and highest GNP concentrations respectively. In conclusion, GNPs are used without any chemical functionalization as the filler in PEEK-based materials, improving the surface hardness and the tribological properties. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Graphical abstract Porphyrins shows an attractive potential to be used on supramolecular optoelectronic materials due to easily coordination with several metal ions, allowing the assembly with peripheral or axial ligands. Herein it’s reported the synthesis and characterization of a novel metalloporphyrin system with 5,10,15,20-(tetra- p -tolyl)porphyrin and iridium(III) where 4,4′-bipyridine coordinate in the axial positions to promote the formation of shish kebab structures. The evaluation of their new properties such as thermal, optical and electrochemical are also presented. Abstract Several organic compounds have been used in optoelectronics devices; porphyrins, due to their interesting optical and electronic properties, have shown an attractive potential to be used on molecular electronics. Among other advantages, porphyrins easily coordinate with several metal ions, which allows the assembly with peripheral or axial ligands introducing new properties to the supramolecular porphyrin. In this work, a new metalloporphyrin system with 5,10,15,20-(tetra- p -tolyl)porphyrin (ttp) and iridium(III) where 4,4′-bipyridine (bpy) coordinate in the axial positions was successfully synthetized, through the formation of “shish kebab” structures. This new compound was characterized through ultraviolet–visible, proton nuclear magnetic resonance, Fourier-transform infrared and Raman spectroscopies, thermogravimetry, differential scanning calorimeter and cyclic voltammetry. The introduction of the bpy on the metalloporphyrin moiety exhibited important influence on the optical, thermal and electrochemical properties. [ABSTRACT FROM AUTHOR]

Highlights • Separate and combined impacts of climate change and land cover scenarios on discharge, SPM and POC load was assessed. • Climate change showed a decrease of discharge, SPM and POC loads as consequence of precipitation decrease and ET increase. • Forest clearcut results in more discharge, SPM and POC loads. • Combined scenarios on discharge, SPM and POC showed a downward trend given by climate change alone. Abstract The separate and combined effects of climate change and forest clearcutting on discharge, suspended particulate matter (SPM) and particulate organic carbon (POC) load at a seasonal and annual scale were evaluated for the Oka catchment. Compared to the baseline scenario (1970–2000), climate change displayed a decrease in annual rainfall (RCP4.5: 27% and RCP8.5: 28%) and an increase in mean temperature (12% for both emission scenarios). Together with the decrease in rainfall, a decrease in discharge and, consequently, in SPM and POC load was also displayed. In RCP4.5, annual discharge, SPM and POC load decreased by 16%, 68% and 38%, respectively. A slightly larger decrease was found in RCP8.5: 21% for discharge, 70% for SPM load and 41% for POC load. Evapotranspiration (ET) increased relative to the baseline, with a change of 15% (RCP4.5) and 16% (RCP8.5). With regard to forest clearcut scenarios, annual discharge ranged between 3% (Scenario 1) and 15% (Scenario 3). At the same time, ET decreased by between 2% (Scenario 1) and 13% (Scenario 3) relative to the baseline (2001–2012). The model predicted a rise in SPM load of between 19% (Scenario 1) and 106% (Scenario 3). The predicted annual POC load ranged between 9% (Scenario 1) and 47% (Scenario 3). The combination of climate change and forest clearcutting scenarios showed a reduction in discharge, SPM and POC load compared to the baseline. Discharge, SPM and POC load decrease ranged between 2–18%, 30–63% and 12–36% in scenarios 8 and 7, respectively. [ABSTRACT FROM AUTHOR]

Abstract Three strains, H01100409BT, H01100413B, and H27100402HT, were isolated from several internal organs of diseased redbanded seabream (Pagrus auriga) reared in Andalusia (Southern Spain). All strains were studied by phenotypic, including chemotaxonomy, and genomic characteristics. Phylogenetic analysis based on concatenated sequences of six housekeeping genes (gyrB , ftsZ , topA , mreB , gapA , and 16S rRNA) supported the inclusion of the strains within the clade Phosphoreum of the genus Photobacterium , and two of the strains (H27100402HT and H01100409BT) formed a tight group separated from the closest species P. aquimaris. Genomic analyses, including average nucleotide identity (ANIb and ANIm) and DNA–DNA hybridization (DDH), clearly separated strains H27100402HT and H01100409BT from the other species within the clade Phosphoreum with values below the thresholds for species delineation. The chemotaxonomic features (including FAME analysis and MALDI-TOF-MS) of H27100402HT and H01100409BT strains confirmed their differentiation from the related taxa. The results demonstrated that strain H01100413B was classified as P. aquimaris and the strains H27100402HT and H01100409BT represented a new species each in the genus Photobacterium , for which we propose the names Photobacterium malacitanum sp. nov., type strain H27100402HT (=CECT 9190T = LMG 29992T), and Photobacterium andalusiense sp. nov., type strain H01100409BT (=CECT 9192T = LMG 29994T). [ABSTRACT FROM AUTHOR]

The increasing production and consumption of Personal Care Products (PCPs), containing UV-filters and musk fragrances, has led to its widespread presence in the aquatic environment which can cause harmful effects to the aquatic organisms due to its intrinsic toxicity. This study aims to evaluate the degree of contamination of wild mussels along the entire Portuguese coastline, continually exposed in their habitat to different contaminants. For this purpose, approximately 1000 mussel specimens were sampled during one year in seven different locations, along the Portuguese coastline. Simultaneous quantification of five UV-filters and seven musks in mussels was achieved by a Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction procedure combined with dispersive liquid-liquid microextraction (DLLME) followed by gas chromatography with mass spectrometry (GC–MS) analysis. Ten out of the twelve target analytes were found in the analysed samples, highlighting the presence of AHTN (tonalide), EHS (2-ethylhexylsalicylate) and EHMC (2-ethylhexyl 4-methoxycinnamate) in all positive samples (93%). Overall, the results obtained indicate a widespread contamination of wild mussels along Portuguese coastline, all over the year. UV-filters were more frequently detected (90%) than musk fragrances (70%) and also quantified at higher levels, with average total concentrations reaching 1155.8 ng/g (dw) against 397.7 ng/g (dw) respectively. A high correlation was observed between the most densely populated and industrialized locations and the higher levels of musks and UV-filters found. In other hand, lower levels of PCPs were found in protected areas. As expected, an increase in UV-filters levels was observed after the summer, likely due to the intense period of recreational activities. [ABSTRACT FROM AUTHOR]

In the present work, carbon dioxide ( CO 2 ) capture capacity was evaluated after a humid impregnation process performed on the surface of open-cell magnesium ( Mg ) foams, with an alkaline solution of lithium hydroxide ( LiOH ) . The Mg foams were fabricated by the infiltration casting method, using irregular particles of sodium chloride ( NaCl ) as space holders. Optical microscopy, helium ( He ) pycnometry and nitrogen ( N 2 ) adsorption-desorption techniques were used to measure the pore size, density ( ρ foam ) and specific surface area ( A s ) , respectively. The microstructural modifications after the impregnation process were analysed by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). Afterwards, a thermogravimetric analysis was performed to evaluate the CO 2 capture capacity under different water steam ( H 2 O ) conditions. After the H 2 O–CO 2 chemisorption process, the carbonated products were identified by the attenuated total reflexion – Fourier transform infrared spectroscopy (ATR-FTIR) technique and then, quantified through a thermal decomposition process. Thermal analysis outcomes showed that H 2 O–CO 2 chemisorption capacity of the Mg foams considerably increased after lithium ( Li ) impregnation. The later as consequence of the lithium oxide ( Li 2 O ) high reactivity with CO 2 , and its effect on the thickening of the oxide film layer formed on the surface of the open-cell Mg foams. These results promote the possible use of this kind of cellular material as structured CO 2 captor, proposing a new functional application for metallic foams and giving an alternative solution to the current environmental issues. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of different strontium ranelate (SrR) doses alone or in combination with low-intensity and high-frequency mechanical vibration (MV) on articular cartilage in ovariectomized rats.Design: Fifty 6-month-old female Wistar rats underwent ovariectomy (OVX) and after 3 months were divided into: control group (Control); SrR 300 mg/kg/day (SrR300); SrR 625 mg/kg/day (SrR625); MV; SrR 625 mg/kg/day plus MV (SrR625 + MV). The vehicle and the SrR were administered by gavage 7 days/week and vibration (0.6 g/60 Hz) was performed for 20 min/day, 5 days/week. Bone mineral density (BMD) and body composition were evaluated by densitometry. Changes in cartilage were assessed 90 days after treatment by histomorphometry; immunohistochemistry analysis evaluating cell death (caspase-3), tumor necrosis factor-α (TNF-α), metalloproteinase 9 (MMP-9) and type II collagen; Osteoarthritis Research Society International (OARSI) grading system and glycosaminoglycans (GAGs) analyses.Results: SrR-treated groups exhibited a lower OARSI grade, a smaller number of chondrocyte clusters, increased levels of chondroitin sulfate (CS) and decreased expression of caspase-3. Additionally, compared to all the groups, SrR300 exhibited increased levels of hyaluronic acid (HA). Vibration applied alone or in combination accelerated cartilage degradation, as demonstrated by increased OARSI grade, reduced number of chondrocytes, increased number of clusters, elevated expression of type II collagen and cell death, and was accompanied by decreased amounts of CS and HA; however, MV alone was able to reduce MMP-9.Conclusions: SrR and vibration modulate distinct responses in cartilage. Combined treatment accelerates degeneration. In contrast, SrR treatment at 300 mg/kg/day attenuates osteoarthritis (OA) progression, improving cartilage matrix quality and preserving cell viability in ovariectomized rats. [ABSTRACT FROM AUTHOR]

A novel and efficient synthesis of dibenzo[ b,e ]oxepin-11(6H)-ones by direct intramolecular ortho -acylation from readily available 2-(phenoxymethyl)benzoic acids was developed. The method takes advantage of a newly developed cooperative system consisting of sustainable FeCl 2 and Cl 2 CHOCH 3 as the key components. This methodology is compatible with a wide variety of functional groups in good to excellent yields and high regioselectivity. The synthetic application of new protocol was extended to the synthesis of known tricyclic drug doxepin as well as a small library of oxepin based derivatives. For the first time, the obtained dibenzo[ b,e ]oxepinone derivatives were evaluated for their biological activities on the free-living nematode Caenorhabditis elegans as an effective and cost-efficient model system for anthelmintic discovery. [ABSTRACT FROM AUTHOR]

Los Humeros Geothermal Field (LHGF) is one of four geothermal fields currently operating in Mexico, in exploitation since 1990. Located in a caldera complex filled with very low-permeability rhyolitic ignimbrites that are the reservoir cap-rock, recharge of the geothermal field is both limited and localized. Because of this, planning of any future geothermal exploitation must be based on a clear understanding of the fluid circulation. To this end, a first noble gas survey was carried out in which twenty-two production wells were sampled for He, Ne, Ar, Kr, and Xe isotope analysis. Air-corrected 3 He/ 4 He ratios (R c ) measured in the fluid, normalized to the helium atmospheric ratio (R a ; 1.384 × 10 − 6 ), are consistently high across the field, with an average value of 7.03 ± 0.40 R a . This value is close to that of the sub-continental upper mantle, indicating that LHGF mines heat from an active magmatic system. Freshwater recharge does not significantly affect He isotopic ratios, contributing 1–10% of the total fluid amount. The presence of radiogenic 40 Ar* in the fluid suggests a fossil fluid component that might have circulated within the metacarbonate basement with radiogenic argon produced from detrital dispersed illite. Solubility-driven elemental fractionation of Ne/Ar, Kr/Ar, and Xe/Ar confirm extreme boiling in the reservoir. However, a combined analysis of these ratios with 40 Ar/ 36 Ar reveals mixing with an air component, possibly introduced by re-injected geothermal fluids. [ABSTRACT FROM AUTHOR]

The structural stability, electronic and magnetic properties of a new silicon carbide fullerene, of chemical composition C 36 Si 24 (SiCF), rich in carbon atoms, were analyzed by means of density functional theory. Calculations were done using a exchange–correlation functional developed by Heyd-Scuseria-Ernzerhof, within the generalized gradient approximation (HSEh1PBE-GGA), and 6-31G(d) basis sets of Pople et al. The DFT simulation results reveal structural stability for the C 36 Si 24 system, which, in a neutral charge state, behaves as semiconductor non-magnetic nanomaterial, since the HOMO-LUMO gap is 0.89 eV. The SiCF system shows marked polarity (1.16 D) and low chemical reactivity. Interestingly, the properties of the silicon carbide fullerene evolve in such way that a semiconducting non-magnetic to conducting magnetic transition is observed for the case where small quantities of nitrogen atoms act as substitutional impurities (C 36-X Si 24 N X ; X = 1, 2, 5, and 10). This electronic behavior was reached for x = 1 and 5 dopes, yielding magnetic moments of 1.0 magneton bohr (μ B ). Additionally, low work function occurs on this CSiN fullerene, which is crucial for the design of electronic devices. [ABSTRACT FROM AUTHOR]

This study is the first comprehensive noble gas study in meltwater of an alpine glacier. It uses stable noble gases' (He, Ne, Ar, Kr, and Xe) concentrations and isotopic ratios from the Athabasca Glacier meltwater (AGMW), Canada, in an attempt to identify the original source location of ice melt and the relative contributions of modern surface melt versus basal melt and/or groundwater. It also estimates first order water residence times of the glacial meltwater (GMW) resulting from a mixture of modern surface and basal melt and/or groundwater. Two patterns are apparent with respect to noble gas concentrations: 1) a mass-dependent depletion pattern with stronger depletion of the heavier noble gases compared to the lighter ones, and 2) a pattern displaying a relative Ne depletion with respect to Ar. Ratios of noble gas concentrations suggest that different gases have different degrees of equilibration and samples are far from equilibration with the atmosphere at any temperature compatible with the glacial environment. Xe concentrations alone suggest that all AGMW samples equilibrated with the atmosphere at altitudes between 2500 m and 3400 m, altitudes that lie within the altitude range (1900 m–3500 m) of the Columbia Icefield. Most samples display Xe equilibration altitudes above the maximum altitude of the AG (∼2700 m), suggesting that a significant portion of the current AGMW originates in the Columbia Icefield which contributes to both the AG per se and current subglacial meltwater discharge. All AGMW samples are largely dominated by surface melt as opposed to basal melt with surface melt representing at least 71%–96% of the total GMW. Basal melt and/or groundwater represent at most 4%–29% of the total GMW. All AGMW samples exhibit tritiogenic 3 He ( 3 He trit ) levels varying between 0 and 12 TU. Based on estimated 3 He trit levels, 4 He concentrations, and average U and Th concentrations in carbonates, we conclude that the bulk of our AGMW is likely a mixture between pre-bomb and present time GMW with a most likely average residence time of 160 ± 5 years with the exclusion of one present day sample. [ABSTRACT FROM AUTHOR]

Four novel heterocycle dyes 3a - d were synthesized in order to study the variations produced in the optical, electronic and photovoltaic properties by substitution of different electron-rich heterocyclic groups to the thieno[3,2- b ]thiophene system. The final push-pull conjugated dyes 3a - d were synthesized by Suzuki-Miyaura coupling reaction followed by Knoevenagel condensation of the corresponding aldehyde precursors with cyanoacrylic acid 2a - d . These new push-pull systems are based on a thieno[3,2- b ]thiophene spacer, a cyanoacetic acid anchoring group and several electron-rich heterocycles (thiophene, pyrrole and furan) as donor groups. The multidisciplinary study concerning the optical, redox and photovoltaic characterization of the dyes reveals that compound 3b bearing a hexyl-bithiophene donor group/heterocyclic spacer exhibits the best overall conversion efficiency (2.49%) as sensitizer in nanocrystalline TiO 2 dye sensitized solar cells. Co-adsorption studies between N719 and 3b revealed that upon addition of N719 co-adsorbent, the optimized cell efficiencies were improved by 16–77%. The best efficiency was 4.40%, corresponding to 54% of the photovoltaic performance of the N719 -based DSSC fabricated and measured under similar conditions. [ABSTRACT FROM AUTHOR]

Vocal fold atrophy and scar can lead to loss of normal superficial lamina propria, negatively affecting the vibratory function of the vocal fold. These changes can lead to dysphonia, vocal fatigue, decreased volume, and altered pitch. Treatment options for these conditions are limited. Platelet-rich plasma (PRP) consists of platelets, growth factors, and cytokines derived from the patient's own blood and is believed to activate tissue regeneration. The purpose of this study was to review the technical aspects of collecting PRP and injecting it into the vocal fold injection – based on our initial experience with this procedure. A patient with vocal fold scar was identified and enrolled in an ongoing prospective clinical trial study of a series of 4 monthly subepithelial vocal fold PRP injections, which was temporarily halted due to the COVID-19 pandemic. Patient underwent a single injection of autologous PRP into the left vocal fold. There were no adverse events during the study period. Subjective improvement in voice was noted at 1 month after injection with subsequent return to baseline over the next 4 months. Videostroboscopy performed on postinjection day 1 and day 7 and demonstrated no concerning exam changes. Compared to the preinjection baseline, the patient-reported voice-handicap index-10 (VHI-10) and voice catastrophization index were similar at 4 months following injection (20 to 20 and 4 to 3, respectively). Independent perceptual analysis of voice showed improvement at 4 months postinjection, compared to baseline consensus auditory-perceptual evaluation of voice 60 to 44. This preliminary report was part of a prospective trial investigating the use of PRP to treat vocal fold atrophy and scar. This work highlights the technical considerations for injecting PRP into the vocal fold. Planned prospective enrollment in this study will help to validate the safety and efficacy of PRP injections. [ABSTRACT FROM AUTHOR]

Stilbenes (diphenylethenes) are fully examined organic chromophores for very diverse applications. However, these molecules might show poor stability under irradiation because several simultaneous reactions (oxidative photocyclization and dimerization) can take place during the photochemical isomerization of their C C bond. In this context, heteroarylethenes emerge as powerful counterparts thanks to their improved stability. In addition, the chosen heterocycles and their functionalization allows to fine tune and increase the speed at which the thermal back reaction occurs, broadening the scope of application of the resulting chromophores. Here we report on the thermal Z -to- E isomerization kinetics of a series of rationally designed heteroarylethenes and how the chemical architecture of the chromophore modulates the speed of the process. Specifically, the metastable Z isomers display relaxation times covering a wide time window, from a few hours to hundreds of microseconds. In fact, one of the studied dyes is the fastest photochromic switch based on heteroarylethenes. It should be also noticed that the described heteroarylethenes exhibit great photochemical stability, it being possible to switch them back and forth many times without degradation. • The thermal isomerization of a series of push-pull heteroarylethenes is explored. • The relaxation time of the chromophores spans from 1.7 h to 191 μs at 296 K. • One of the chromophores is the fastest ethene dye reported heretofore. • This photoswitch can be operated more than 1000 cycles with no sign of fatigue. • Such system can be used as an optical oscillator with a frequency of 1.7 kHz. [ABSTRACT FROM AUTHOR]

An understanding of the processes controlling sediment, organic matter and metal export is critical to assessing and anticipating risk situations in water systems. Concentrations of suspended particulate matter (SPM), dissolved (DOC) and particulate (POC) organic carbon and metals (Cu, Ni, Pb, Cr, Zn, Mn, Fe) in dissolved and particulate phases were monitored in a forest watershed in the Basque Country (Northern Spain) (31.5 km 2 ) over three hydrological years (2009–2012), to evaluate the effect of flood events on the transport of these materials. Good regression was found between SPM and particulate metal concentration, making it possible to compute the load during the twenty five flood events that occurred during the study period at an annual scale. Particulate metals were exported in the following order: Fe > Mn > Zn > Cr > Pb > Cu > Ni. Annual mean loads of SPM, DOC and POC were estimated at 2267 t, 104 t and 57 t, respectively, and the load (kg) of particulate metals at 76 (Ni), 83 (Cu), 135 (Pb), 256 (Cr), 532 (Zn), 1783 (Mn) and 95170 (Fe). Flood events constituted 91%-SPM, 65%-DOC, 71%-POC, 80%-Cu, 85%-Ni, 72%-Pb, 84%-Cr, 74%-Zn, 87%-Mn and 88%-Fe of total load exported during the three years studied. Flood events were classified into three categories according to their capacity for transporting organic carbon and particulate metals. High intensity flood events are those with high transport capacity of SPM, organic carbon and particulate metals. Most of the SPM, DOC, POC and particulate metal load was exported by this type of flood event, which contributed 59% of SPM, 45% of organic carbon and 54% of metals. [ABSTRACT FROM AUTHOR]

Novel push–pull second harmonic generation (SHG) chromophores 3-6 were synthesized in order to study how their optical properties are affected by an increase in the size of the π-bridge and also by connecting different electron accepting moieties (dicyanovinyl- and tricyanovinyl) to the (bi)thienylpyrrole system at position 5 of the pyrrole ring or at position 5 of the thiophene heterocycle. The precursor aldehydes were prepared through two different synthetic methodologies: Suzuki coupling ( 5a - b ) or Suzuki coupling followed by Vilsmeier formylation ( 2a - b ). The final donor-acceptor systems 4-6 were prepared by tricyanovinylation reaction of precursors 1a - b or by Knoevenagel reaction of the precursor aldehydes 2b or 5b with malononitrile. Hyper-Rayleigh scattering in dioxane solutions using a fundamental wavelength of 1064 nm was employed to evaluate their second-order nonlinear optical properties. The experimental results showed that the optical properties are influenced by the electron-acceptor strength of the groups, the length of the π-spacer/donor group as well as by the relative position of the pyrrole and thiophene heterocycles to the acceptor groups. The dicyanovinyl derivative 6b , which embodies the longer π-conjugated bridge functionalized in the thiophene ring, exhibited the largest first hyperpolarizability ( β = 10,900 × 10 −30 esu, using the T convention) thus indicating its potential application as a SHG chromophore. As far as we are aware, this represents the largest hyperpolarizability reported to date for a bithienylpyrrole derivative. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is an extracellular polymer produced by many microorganisms. The Komagataeibacter genus is the best producer using semi-synthetic media and agricultural wastes. The main advantages of BC are the nanoporous structure, high water content and free hydroxyl groups. Modification of BC can be made by two strategies: in-situ , during the BC production, and ex-situ after BC purification. In bioprocesses, multilayer BC nanocomposites can contain biocatalysts designed to be suitable for outside to inside cell activities. These nanocomposites biocatalysts can (i) increase productivity in bioreactors and bioprocessing, (ii) provide cell activities does not possess without DNA cloning and (iii) provide novel nano-carriers for cell inside activity and bioprocessing. In nanomedicine, BC matrices containing therapeutic molecules can be used for pathologies like skin burns, and implantable therapeutic devices. In nanoelectronics, semiconductors BC-based using salts and synthetic polymers brings novel films showing excellent optical and photochemical properties. [ABSTRACT FROM AUTHOR]

A new series of push–pull nonlinear optical (NLO) chromophores 2 and 3 were synthesized in order to study the variations produced in the optical properties of the compounds by linking different electron accepting moieties to the pyrrolyl-thiazole system at position 5 of the electron deficient thiazole heterocycle. The final donor–acceptor systems 3a – c were synthesized by a modification of the Paal–Knorr synthesis (the Clauson-Kaas reaction) followed by Knoevenagel reaction of the precursor aldehydes 2a – c with active methylene molecules. Hyper-Rayleigh scattering in dioxane solutions using a fundamental wavelength of 1064 nm was employed to evaluate their second-order nonlinear optical properties. An indanone dicyanovinyl derivative 3c exhibited the largest first hyperpolarizability ( β = 970 × 10 −30 esu, using the T convention) as well the highest value of decomposition, T d = 300 °C thus indicating its potential application as a second harmonic generation (SHG) chromophore. [ABSTRACT FROM AUTHOR]

Natural fibres are increasingly used as reinforcements for thermoplastic composites. Additive manufacturing, also known as 3D printing, is a common material extrusion process using (bio)polymers reinforced with natural fibres. However, there is a lack of understanding of the effect of printing parameters on the mechanical properties involved in this new process, and more particularly in the case of Fused Deposition Modeling (FDM). Hygromorphic biocomposites represent a novel use of natural fibres for the production of original self-bending devices that actuate in a moisture gradient. By mimicking natural actuators and their bilayer microstructure adapted for seed dispersal, hygromorphic biocomposites take advantage of the hygro-elastic behaviour of natural fibres. The FDM of wood fibre reinforced biocomposites leads to mechanical properties that are strongly dependent on printing orientation (0 or 90°) due to fibre anisotropy. Mechanical properties depend also on printing width (overlapping of filaments), with a lower Young's modulus than in the compressed samples. Indeed, printed biocomposites have a microstructure with relatively high porosity (around 20%) that conjointly leads to damage mechanisms but also water absorption and swelling. The FDM of hygromorphic biocomposites enables a shift towards 4D printing since the material is able to evolve over time in response to an external stimulus. Typical microstructures achieved by printing could be used advantageously to produce biocomposites with a faster moisture-induced bending response compared to compressed samples. [ABSTRACT FROM AUTHOR]

A series of thienylpyrroles and bithienylpyrroles together with their formyl derivatives 5a – d were synthesized using commercially or readily available coupling components, through three different palladium catalyzed cross-coupling reactions (Suzuki-Miyaura, Stille and decarboxylative coupling). The synthesis of compounds 5 via the Suzuki-Miyaura reaction produced the title compounds in better yields than the other coupling reactions, while, decarboxylative coupling resulted in the lower yields. UV–visible and 1 H NMR studies confirm the existence of significant intramolecular charge transfer (ICT) from the donor pyrrole heterocycle to the acceptor group and a high polarizability of the whole π-conjugated systems. Together these characteristics indicate their strong potential as versatile precursors for the preparation of push-pull heterocyclic compounds for optical applications. [ABSTRACT FROM AUTHOR]

Hypothesis: Crack-cocaine addiction is associated with a variety of conditions that increase risk of thiamine deficiency and Wernicke's encephalopathy.Evidence: We report a case of Wernicke's encephalopathy in a crack-cocaine addict who did not habitually consume alcohol. We list some conditions associated with crack-cocaine addiction that may contribute to thiamine deficiency.Implications: Clinicians should bear in mind that crack-cocaine addiction may be associated with Wernicke's encephalopathy, mainly due to malnutrition. We suggest that routine Wernicke's encephalopathy prophylaxis with parenteral thiamine be provided to patients with chronic crack-cocaine addiction, as is already established practice in chronic alcoholics, so as to prevent cognitive damage in this population. [ABSTRACT FROM AUTHOR]

Under low energy ion irradiation, periodic features (ripples) can develop on the surfaces of semiconductor materials, with typical sizes in the nanometric range. Recently, a theory of pattern formation has been able to account for the variability with the ion/target combination of the critical angle value separating conditions on ion incidence that induce the presence or the absence of ripples. Such a theory is based in the accumulation of stress in the damaged irradiated layer and its relaxation via surface-confined viscous flow. Here we explore the role of stress, and its competition with purely erosive mechanisms, to determine the sign of the velocity with which the ripple pattern moves across the target plane. Based on this theory, we discuss different situations and make specific testable predictions for the change of sign in that velocity. [ABSTRACT FROM AUTHOR]

We extend to a situation involving matrix valued orthogonal polynomials a scalar result that originates in work of Claude Shannon in laying the mathematical foundations of information theory and a remarkable series of papers by D. Slepian, H. Landau and H. Pollak at Bell Labs in the 1960's. We show that in this case an algebraic miracle that plays a very important role in the classical case survives an application of the so-called Darboux process in the matrix valued context. [ABSTRACT FROM AUTHOR]

This study uses stable noble gases' (He, Ne, Ar, Kr, Xe) volume fractions and isotopic ratios from Antrim Shale natural gas to assess compositional variability and vertical fluid migration within this reservoir, in addition to distinguishing between the presence of thermogenic versus biogenic methane. R/Ra values, where R is the measured 3 He/ 4 He ratio and Ra is the atmospheric value of 1.384 ± 0.013 × 10 − 6 , vary from 0.01 to 0.34 suggesting a largely dominant crustal 4 He component with minor atmospheric and mantle contributions. Crustal 21 Ne, 40 Ar and 136 Xe contributions are also present but the atmospheric component is largely dominant for these gases. Crustal contributions for 21 Ne, 40 Ar and 136 Xe vary between 1.1% and 12.5%, between 0.7% and 19% and between 0.1% and 2.7%, respectively. A few samples present higher than atmospheric 20 Ne/ 22 Ne ratios pointing to the presence of a small mantle Ne component. High horizontal and vertical variability of noble gas signatures in the Antrim Shale are observed. These are mainly due to variable noble gas input from deep brines and, to a smaller extent, variable in-situ production within different layers of the Antrim Shale, in particular, the Lachine and Norwood members. Estimated 4 He ages, considering external 4 He input for Antrim Shale water, vary between 0.9 ka and 238.2 ka and match well for most samples with the timing of the major Wisconsin glaciation, suggesting that Antrim Shale water was influenced by glaciation-induced recharge. Consistency between measured and predicted 40 Ar/ 36 Ar ratios assuming Ar release temperatures ≥ 250 °C supports a thermogenic origin for most of the methane in these samples. This thermogenic methane is likely to originate at greater depths, either from the deeper portion of the Antrim Shale in the central portion of the Michigan Basin or from deeper formations given that the thermal maturity of the Antrim Shale in the study area is rather low. [ABSTRACT FROM AUTHOR]

The vapour sensing performances of various surfactant–carbon nanotube (CNT) sensors fabricated by spray layer by layer (sLbL) towards various VOC including eleven lung cancer biomarkers have been investigated. It is found that changing the surfactants’ nature allows to efficiently tailor both the selectivity and the sensitivity of CNT vapour sensors to detect specifically some VOC biomarkers of lung cancer. An original boosting effect of chemo-resistive responses has also been evidenced and assumed to result from the combined expansion of surfactant molecules directly sheathing CNT at junctions and of those organised in micelles in the vicinity of CNT, upon analytes’ diffusion. The performances of surfactant–CNT sensors, hierarchically structured by sLbL with sodium deoxycholate (DOC), sodium dodecylbenzenesulfonate (SDBS), 1-hexadecyl trimethyl ammonium bromide (CTAB), benzalkonium chloride (BnzlkCl), and triton ® x-405 (TX405) were found to depend on the interactions of the surfactants with the analytes, on their supramolecular assembly with CNT but also on the initial resistance R 0 that can be adjusted by CNT content, surfactant:CNT ratio or the surfactant concentration over its CMC. CNT-DOC sensors were found sensitive to methanol and other alcohols but also water. TX405-CNT sensors were found sensitive to benzene, n -pentane and chloroform. SDBS-CNT sensors could detect ethanol, acetone, chloroform and water but not much biomarkers, excepted isopropanol. BnzlkCl-CNT sensors were sensitive to n -pentane, isoprene, acetone and ethanol. CTAB-CNT sensors were slightly sensitive to most VOC but did not show any strong selectivity, whereas pristine CNT sensors were found to be good to detect most aromatic VOC of the set. Moreover it is remarkable that the technique of fabrication used here is almost exclusively based on eco-friendly aqueous solutions of CNT. [ABSTRACT FROM AUTHOR]

Background: Inotropes and vasopressors are frequently administered to critically ill patients in order to improve haemodynamic function and restore adequate organ perfusion. However, some studies have suggested a possible association between inotrope administration and increased mortality. We therefore performed a meta-analysis of randomized trials published in the last 20 yr to investigate the effect of these drugs on mortality.Methods: BioMedCentral, PubMed, Embase and the Cochrane Central Register were searched (all updated April 8th, 2015). Inclusion criteria were: random allocation to treatment, at least one group receiving an inotropic or vasopressor drug compared with at least one group receiving a non-inotropic/vasopressor treatment, study published after 1st January 1994, and systemic drug administration. Exclusion criteria were overlapping populations, studies published as abstract only, crossover studies, paediatric studies and lack of data on mortality.Results: A total of 28 280 patients from 177 trials were included. Overall, pooled estimates showed no difference in mortality between the group receiving inotropes/vasopressors and the control group [4255/14 036 (31.7%) vs. 4277/14 244 (31.8%), risk ratio=0.98 (0.96-1.01), P for effect=0.23, P for heterogeneity=0.30, I2=6%]. A reduction in mortality was associated with inotrope/vasopressor therapy use in settings of vasoplegic syndromes, sepsis and cardiac surgery. Levosimendan was the only drug associated with improvement in survival. Subgroup analysis did not identify any groups with increased mortality associated with inotrope/vasopressor therapy.Conclusions: Our systematic review found that inotrope/vasopressor therapy is not associated with differences in mortality in the overall population and in the majority of subsettings. [ABSTRACT FROM AUTHOR]

In this work we present experimental results from dynamic and static tests on miniature magnetic field sensors which are based on Micro Electro Mechanical Systems (MEMS) technologies. These MEMS magnetometers were fabricated on SOI wafers using Si bulk micromachining techniques and they operate at the first resonant frequency under the action of the Lorentz force which arises when a current flows through them in the presence of an external magnetic field. Sensing is based on piezoresistive principles and high sensitivity is expected from devices that show high total quality factors Q tot . We investigate here the energy loss mechanisms and the temperature rise due to Joule heating effects in the resonators of the magnetometers by performing tests both in air and under vacuum conditions. Testing was performed using laser Doppler Vibrometry and white light interferometry. At each pressure different driving currents have been applied and Q tot was extracted. It is found that Q tot varies with pressure between two limiting values: a low one in air which was between 17 and 500 for the tested devices and a high one in vacuum which in the case of one of our devices was equal to 2800. The amplitude of the applied current is also affecting the Q value at a certain pressure due to the rise of thermal stress in the resonating structures. The sensitivity of the sensors in air was experimentally measured using a Helmholtz coil and an oscilloscope and values between 72 mV T −1 and 513 mV T −1 were obtained from the tested devices. We further attempt to estimate the temperature rise in the devices due to Joule heating effects by combining the topography scans which were experimentally obtained with results from thermomechanical analysis of the sensors using Finite Element Modelling. [ABSTRACT FROM AUTHOR]

Pine cone scales exhibit moisture-induced bending actuation which is driven by their bilayered architecture made up of tissues with different hygroscopic properties. Inspired by this mechanism, we describe the behaviour of moisture-induced self-shaping biocomposites displaying a bilayer structure. Even though plant fibres are assumed to display weaknesses as a reinforcing agent in the field of structural biocomposites, i.e . due to their high water absorption and swelling, this behaviour can be used as a driving force when considering an additional biocomposite function such as actuation. A reversible bending is obtained when the studied biocomposite is immersed and then taken out of water. In fact, moisture displacement during wetting / drying steps appears to exert a linear control on the amplitude and rate of movement. Although motion is relatively slow compared to natural actuators such as pine cones, we can nevertheless envisage further material optimizations. [ABSTRACT FROM AUTHOR]

Lake Bonney (LB), located in Taylor valley, Antarctica, is a perennially ice-covered lake with two lobes, West Lake Bonney (WLB) and East Lake Bonney (ELB), which are separated by a narrow ridge. Numerous studies have attempted to reconstruct the evolution of LB because of its sensitivity to climatic variations and the lack of reliable millennial-scale continental records of climate in this region of Antarctica. However, these studies are limited by the availability of accurate lacustrine chronologies. Here, we attempt to better constrain the chronology of LB and thus, the evolution of past regional climate by estimating water residence times based on He, Ne and Ar concentrations and isotopic ratios in both WLB and ELB. 3 He and 4 He excesses up to two and three orders of magnitude and 35–150 times the atmospheric values are observed for WLB and ELB samples, respectively. In comparison, while measured 40 Ar/ 36 Ar ratios are atmospheric (∼295.5) in ELB, WLB samples display 40 Ar/ 36 Ar ratios of up to ∼315 reflecting addition of radiogenic 40 Ar. Both 4 He and 40 Ar excesses clearly identify the addition of subglacial discharge (SGD) from underneath Taylor Glacier into WLB at depths of 25 m and 35 m. He isotopic ratios suggest that He excesses are predominantly crustal (>93%) in origin with small mantle contributions (<7%). These crustal 4 He and 40 Ar excesses are used together with basement rock production rates of these isotopes to derive first-order approximations of water residence times for both lobes. Numerous factors capable of affecting water residence times are evaluated and corrected 4 He and 40 Ar water ages are used to place further constrains into the reconstruction of both WLB and ELB history. Combined 4 He and 40 Ar ages in WLB suggest maximum water residence times of ∼250 kyrs BP. These results support the presence of remnant water from proglacial lakes that existed during Marine Isotope Stage 7 (160–240 kyrs) in WLB, in agreement with previous studies. In comparison, 4 He ages in ELB are much younger (<27 kyrs BP) and display a complex evolutionary history that is very different from WLB. 4 He ages also suggest that the ELB ice cover formed significantly earlier (∼1.5 kyrs BP) than previously reported. The timing of these hydrologic changes in ELB appears to correspond to regional and global climatic events that are recorded in both the Taylor Dome ice-core record as well as in other Dry Valley Lakes. [ABSTRACT FROM AUTHOR]

We present a microelectromechanical system (MEMS)-based magnetic field sensor with simple structural configuration, low power consumption, and linear electrical response. This sensor operates with Lorentz force and uses piezoresistive sensing. Its resonant silicon structure consists of a perforated plate (472 × 300 × 15 μm), four flexural beams (18 × 15 × 15 μm), two support beams (60 × 36 × 15 μm), and an aluminum loop (9 × 2 μm cross-section), which are fabricated using a standard bulk micromachining process. The sensor works at its first seesaw resonant frequency without a vacuum packaging. Analytical and finite element method (FEM) models are developed to predict the mechanical behavior of the sensor structure considering the main damping sources. The experimental seesaw resonant frequency and quality factor of the sensor are 100.7 kHz and 419.6, respectively. The sensor has a linear electrical response and its detection range can be easily adjusted. For a DC bias voltage ( V in ) of 3 V and a bandwidth of 240 Hz, the sensor has sensitivity, resolution, and power consumption of 230 mV⋅T –1 , 2.5 μT, and 12 mW, respectively. This sensor could be used in non-destructive magnetic testing for monitoring geometrical defects and corrosion of ferromagnetic materials. [ABSTRACT FROM AUTHOR]

Materials, and particularly glasses, with a tailor-made spectral optical response that can be switched in a controlled way using external stimuli excitation are of interest for the development of active optical devices, such as active filters or all-optical switching components. Based on the dielectric functions of solid and liquid bismuth (Bi), it is expected that both solid and liquid Bi nanostructures will show optical resonances with relevant different features in the near ultraviolet to near infrared. In addition, Bi has a low melting point that enables the solid–liquid phase change under moderate heating. Profiting of these singular properties we present and review in this paper the main results that have been obtained in our laboratory concerning the thermo-optical response of bulk germanate glasses and amorphous Al 2 O 3 thin films with embedded Bi nanoparticles (NPs). In both materials the optical transmission as a function of the temperature shows broad hysteresis loops. The optical contrast and width of these cycles depend on the Bi content and NP size. From the successful modelling of the optical properties of the Bi NPs-doped glasses, it is proposed that the observed material thermo-optical response arises from the change in the dielectric function of the Bi NPs upon melting, which induces relevant changes in the resonant optical behaviour of the Bi NPs. These results suggest that glasses with embedded Bi NPs are promising for the design of spectral-selective thermo-optical devices. [ABSTRACT FROM AUTHOR]

A series of novel photochromic cationic stilbenes dyes bearing different aromatic systems were easily synthesized from (hetero)aromatic aldehydes. The photoisomerization of the double bond can be achieved through irradiation with ultraviolet or visible light, for few seconds, leading to the Z isomers that return much faster to the initial state than common stilbenes. Benzothiazolium dyes with electron donating substituents exhibited very fast thermal back reactions (<1 s). Pyrrole-benzothiazolium dye showed a higher lifetime of the Z isomer, in different solvents, including water (0.45–7.1 min). This cationic diarylethene can be switched between the E-Z states using visible light, in few minutes at room temperature, with a noticeable change in the visible spectrum. [ABSTRACT FROM AUTHOR]

Background Severe chronic kidney disease is a major limitation for endovascular aortic aneurysm repair (EVAR). The aim of this study is to assess the safety and accuracy of fusion imaging, when performing EVAR in the absence of pre- and intra-operative contrast agents. Methods From October 2013 to February 2014, every patient requiring EVAR and presenting with severe chronic renal impairment underwent a specific pre-operative imaging assessment, based on a non-enhanced CT scan. Centrelines were manually extracted and key points were placed at the landing zones. In house software makes it possible to artificially enhance the contrast between vascular structures and the surrounding tissue, by increasing the values attributed to the vascular structure voxels (500 Hounsfield units). EVAR was performed in a hybrid room (Zeego, Siemens), and the artificially enhanced CT scan was used for the construction of fusion imaging. The 3D vascular volume, together with the centrelines and key points, was overlaid onto the 2D live fluoroscopic image. Results Six patients (mean age 77.1 years) were treated by EVAR (5 abdominal aneurysms and 1 thoracic aneurysm), using fusion imaging without a contrast agent. The median pre-operative estimated glomerular filtration rate (eGFR) was 17.5 mL/min/1.73 m 2 . No contrast was used during the procedure. No intra-operative endoleak was observed on the duplex scan. No deterioration was observed in the eGFR at 1 week (eGFR = 21.7, p = .49), nor at 1 month follow up (eGFR = 21, p = .28). The stent graft positioning error was assessed in terms of the difference between the effective and planned landing zones, measured on pre- and post-operative CT scans. The mean error was 1.3 mm at the proximal landing zone, and 6.5 mm at the distal landing zone. Conclusion EVAR without the use of pre-operative and intra-operative contrast agents appears to be safe and accurate for patients with severe chronic kidney disease. [ABSTRACT FROM AUTHOR]

The use of composite materials in large structures such as wind turbine blades, proposed as a renewable energy solution, is currently increasing. Due to their expected lifetime, they may be subjected to a variety of punctual damaging events, such as impacts. The extent of damage caused by impacts can range from weak (rain) to locally destructive (birds). Detecting and locating these impacts could help assess the health of the part, monitor its state and could lead to a better prediction of its ultimate failure, thus reducing maintenance cost, within a broader framework of structural health monitoring. Here, we studied the use of Quantum Resistive Sensors (QRSs) for the detection and localisation of impacts that could be whether hail, bird or maintenance tool impacts occurring on an epoxy-glass fibre laminate. At an acquisition frequency of 4800 Hz, the electrical behaviour of QRSs was found to be simultaneous with the impact load. The use of multiple sensors within and between plies further evidenced that the change in resistance is proportional to the impact energy and could help to locate the impact area. The effect of repeated impacts on the electrical properties of the QRSs was then studied. With the accumulation of impacts that have reduced Young's modulus of the sample, both the resistance at rest and the amplitude of the response during dynamic cycle increased. Therefore, QRSs could provide an in situ probe in composites to detect, localize, quantify the energy of an impact to anticipate the resulting drops in mechanical properties of the composite. [Display omitted] • CNT-based Quantum Resistive Sensors are embedded in and between plies of GFRP. • QRS signal is in phase with the impact load and proportional to its intensity. • Amplitude of electrical signal is related to location and vicinity to the impacted zone. • Health state of GFRP is monitored by QRS during impact/cyclic bending sequences. [ABSTRACT FROM AUTHOR]