Higher daily temperature range at depth is linked with higher thermotolerance in antipatharians from the canary islands.

Sensitivity to ocean warming is generally expected to be lower in populations from more heterogeneous thermal environments, owing to greater phenotypic plasticity and/or genotype selection. While resilience of benthic populations from thermally fluctuating environments has been investigated at a variety of spatial scales, this has received limited attention across depths and has remained unresolved for Antipatharian corals, key habitat-forming species across a wide bathymetric range in all of the world oceans. In this study, we aimed at addressing the thermal sensitivity of Antipatharian corals across depths characterized by different levels of temperature fluctuations. We used an acute ramping experimental approach to compare the thermal sensitivity of colonies of (1) the branched Antipatharian Antipathella wollastoni (Gray, 1857) from two distinct depths (25 and 40 m) in Gran Canaria (Canary Islands, Spain); and of (2) unbranched mesophotic (80 m) Stichopathes species, from Lanzarote (Canary Islands, Spain; S. gracilis (Gray, 1857)), and Stichopathes sp. clade C from Mo'orea, French Polynesia. Results showed that the daily temperature range in Gran Canaria was larger at mesophotic depths (3.9 °C vs. 2.8 °C at 40 and 25 m, respectively) and this coincided with lower thermal sensitivity in mesophotic colonies of A. wollastoni. Second, S. gracilis from Lanzarote showed a lower thermal sensitivity than the previously studied Stichopathes sp. clade C from Mo'orea (French Polynesia) inhabiting a less variable habitat. These results are in line with the climate variability hypothesis, which states that populations under more variable thermal conditions have a lower sensitivity to warming than those from more stable environments, as they have adapted/acclimated to these higher levels of temperature fluctuations.

Balancing the Strength-Impact Relationship and Other Key Properties in Polypropylene Copolymer-Natural CaSO4 (Anhydrite)-Filled Composites.

To develop novel mineral-filled composites and assess their enhanced properties (stiffness, a good balance between mechanical strength and impact resistance, greater temperature stability), a high-impact polypropylene copolymer (PPc) matrix containing an elastomeric discrete phase was melt mixed with natural CaSO4 ß-anhydrite II (AII) produced from gypsum rocks. First, in a prior investigation, the PPc composites filled with AII (without any modification) displayed enhanced stiffness, which is correlated with the relative content of the filler. The tensile and impact strengths dramatically decreased, especially at high filling (40 wt.%). Therefore, two key methods were considered to tune up their properties: (a) the ionomeric modification of PPc composites by reactive extrusion (REx) with zinc diacrylate (ZA), and (b) the melt mixing of PPc with AII surface modified with ethylenebis(stearamide) (EBS), which is a multifunctional processing/dispersant additive. The properties of composites produced with twin-screw extruders (TSEs) were deeply assessed in terms of morphology, mechanical, and thermal performance, including characterizations under dynamic mechanical solicitations at low and high temperatures. Two categories of products with distinct properties are obtained. The ionomeric modification by Rex (evaluated by FTIR) led to composites characterized by remarkable thermal stability, a higher temperature of crystallization, stronger interfacial interactions, and therefore noticeable mechanical properties (high tensile strength (i.e., 28 MPa), increased stiffness, moderate (3.3 kJ/m2) to good (5.0 kJ/m2) impact resistance) as well as advanced heat deflection temperature (HDT). On the other hand, the surface modification of AII with EBS facilitated the dispersion and debonding of microparticles, leading to composites revealing improved ductility (strain at break from 50% to 260%) and enhanced impact properties (4.3-5.3 kJ/m2), even at high filling. Characterized by notable mechanical and thermal performances, high whiteness, and a good processing ability, these new PPc-AII composites may be tailored to meet the requirements of end-use applications, ranging from packaging to automotive components.

Expiratory central airway collapse during positive pressure ventilation: a case report.

BACKGROUND: Physiologic narrowing of the central airway occurs during expiration. Conditions in which this narrowing becomes excessive are referred to as expiratory central airway collapse. Expiratory central airway collapse is usually managed by applying positive pressure to the airways, which acts as a pneumatic stent. The particularity of the case reported here included the patient's left main bronchus being permeable during spontaneous breathing but collapsing during general anaesthesia, despite positive pressure ventilation and positive end-expiratory pressure. CASE PRESENTATION: We present the case of a 55-year-old man admitted for the placement of a ureteral JJ stent. Rapid desaturation occurred a few minutes after the onset of anaesthesia. After excluding the most common causes of desaturation, fibreoptic bronchoscopy was performed through the tracheal tube and revealed complete collapse of the left main bronchus. The collapse persisted despite the application of positive end-expiratory pressure and several recruitment manoeuvres. After recovery of spontaneous ventilation, the collapse was lifted, and saturation increased back to normal levels. No evidence of extrinsic compression was found on chest X-rays or computed tomography scans. CONCLUSION: Cases of unknown expiratory central airway collapse reported in the literature were usually managed with positive pressure ventilation. This approach has been unsuccessful in the case described herein. Our hypothesis is that mechanical bending of the left main bronchus occurred due to loss of the patient's natural position and thoracic muscle tone under general anaesthesia with neuromuscular blockade. When possible, spontaneous ventilation should be maintained in patients with known or suspected ECAC.

Evaluation of the impact of deep neuromuscular blockade on surgical conditions for laryngeal microsurgery with High Frequency Jet Ventilation. A comparison with no block during intravenous general anesthesia with topical lidocaine.

OBJECTIVE: Laryngeal transoral surgery classically requires a neuromuscular block (NMB) to facilitate tracheal intubation and to improve surgical conditions. However, the short duration of most procedures and the potential complications of residual NMB lead to consider a no block approach. The hypothesis that intravenous anesthesia (remifentanil and propofol infusions) without NMB but including glottis topical lidocaine anesthesia would allow clinically acceptable laryngeal exposure and good surgical conditions was tested in the specific context of procedures undergone with High Frequency Jet Ventilation (HFJV). STUDY DESIGN: A prospective randomized clinical comparison. METHODS: 66 consenting patients were planned to receive 0.6 mg·kg-1 rocuronium or saline at random. The outcome measurements included the time and conditions to complete suspended laryngoscopy, and the surgical conditions rated by the surgeon. Any vocal cord movement or coughing was recorded. Data were compared using a Wilcoxon rank-sum test for numerical variables and chi-square test for categorical ones. Treatment failure was defined as an impossible laryngoscopy or a grade 4 surgical field occurring at any time during surgery and was compared to its null theoretical value by a general z-test. An interim analysis after completion of 50% patients was performed using Pocock boundaries at 0.0294 significance levels. RESULTS: A significant failure rate occurred in the non paralysed group (27%, p < 0.001). No coughing and no vocal cords movement occurred in the NMB group. Poorer surgical conditions were obtained without NMB (p = 0.011). CONCLUSION: Inducing a deep NMB ensured improved conditions during direct laryngeal microsurgery with HFJV.

The interest of 100 versus 200 Hz tetanic stimulations to quantify low levels of residual neuromuscular blockade with mechanomyography: a pilot study.

A more sensitive method than the train-of-four ratio seems required to detect low levels of residual neuromuscular blockade before tracheal extubation. The goal of the study was to determine the potential benefit of 5 s of 100 versus 200 Hz tetanic stimulation to quantify the residual block with mechanomyography in anesthetised patients. Twenty informed and consenting 18- to 80-year-old patients undergoing nose surgery were included. On the left hand, neuromuscular transmission was continuously monitored by acceleromyography. On the right side, a new mecanomyographic device (Isometric Thumb Force©) recorded the force of thumb adduction (N) developed during 5 s of 100- and 200 Hz tetanic stimulations of the ulnar nerve at three consecutive times: baseline before inducing the neuromuscular blockade, at the time of contralateral train-of-four ratio 0.9 recovery, and 3 min after additional sugammadex reversal. Tetanic Fade Ratios (TFR = F residual/F max) were compared between 100 and 200 Hz stimulations using Student's t test. At the time of TOF ratio 0.9 recovery, both 100 and 200 Hz TFR were significantly decreased compared to baseline (0.61 and 0.16 on average, respectively, p < 0.0001). The 200 Hz TFR was significantly lower than the 100 Hz TFR (p < 0.0001). There were no differences between baseline and post-reversal TFR. The 200 Hz TFR has the potential to better describe low levels of residual neuromuscular blockade than the TOF ratio and 100 Hz TFR and would benefit from further investigations. Retrospectively registered in the Australian and New Zealand Clinical Trials Registry ACTRN12619000273189.

Acid-base balance in the hæmolymph of European abalone (Haliotis tuberculata) exposed to CO2-induced ocean acidification.

Ocean acidification (OA) and the associated changes in seawater carbonate chemistry pose a threat to calcifying organisms. This is particularly serious for shelled molluscs, in which shell growth and microstructure has been shown to be highly sensitive to OA. To improve our understanding of the responses of abalone to OA, this study investigated the effects of CO2-induced ocean acidification on extra-cellular acid-base parameters in the European abalone Haliotis tuberculata. Three-year-old adult abalone were exposed for 15 days to three different pH levels (7.9, 7.7, 7.4) representing current and predicted near-future conditions. Hæmolymph pH and total alkalinity were measured at different time points during exposure and used to calculate the carbonate parameters of the extracellular fluid. Total protein content was also measured to determine whether seawater acidification influences the composition and buffer capacity of hæmolymph. Extracellular pH was maintained at seawater pH 7.7 indicating that abalones are able to buffer moderate acidification (-0.2 pH units). This was not due to an accumulation of HCO3- ions but rather to a high hæmolymph protein concentration. By contrast, hæmolymph pH was significantly decreased after 5 days of exposure to pH 7.4, indicating that abalone do not compensate for higher decreases in seawater pH. Total alkalinity and dissolved inorganic carbon were also significantly decreased after 15 days of low pH exposure. It is concluded that changes in the acid-base balance of the hæmolymph might be involved in deleterious effects recorded in adult H. tuberculata facing severe OA stress. This would impact both the ecology and aquaculture of this commercially important species.

Adding Value in Production of Multifunctional Polylactide (PLA)-ZnO Nanocomposite Films through Alternative Manufacturing Methods.

Due to the added value conferred by zinc oxide (ZnO) nanofiller, e.g., UV protection, antibacterial action, gas-barrier properties, poly(lactic acid) (PLA)-ZnO nanocomposites show increased interest for utilization as films, textile fibers, and injection molding items. The study highlights the beneficial effects of premixing ZnO in PLA under given conditions and its use as masterbatch (MB), a very promising alternative manufacturing technique. This approach allows reducing the residence time at high processing temperature of the thermo-sensitive PLA matrix in contact of ZnO nanoparticles known for their aptitude to promote degradation effects onto the polyester chains. Various PLA-ZnO MBs containing high contents of silane-treated ZnO nanoparticles (up to 40 wt.% nanofiller specifically treated with triethoxycaprylylsilane) were produced by melt-compounding using twin-screw extruders. Subsequently, the selected MBs were melt blended with pristine PLA to produce nanocomposite films containing 1-3 wt.% ZnO. By comparison to the more traditional multi-step process, the MB approach allowed the production of nanocomposites (films) having improved processing and enhanced properties: PLA chains displaying higher molecular weights, improved thermal stability, fine nanofiller distribution, and thermo-mechanical characteristic features, while the UV protection was confirmed by UV-vis spectroscopy measurements. The MB alternative is viewed as a promising flexible technique able to open new perspectives to produce more competitive multifunctional PLA-ZnO nanocomposites.

Interphase Design of Cellulose Nanocrystals/Poly(hydroxybutyrate-ran-valerate) Bionanocomposites for Mechanical and Thermal Properties Tuning.

Poly[(3-hydroxybutyrate)-ran-(3-hydroxyvalerate)] (PHBV) is a bacterial polyester with a strong potential as a substitute for oil-based thermoplastics due to its biodegradability and renewability. However, its inherent slow crystallization rate limits its thermomechanical properties and therefore its applications. In this work, surface-modified cellulose nanocrystals (CNCs) have been investigated as green and biosourced nucleating and reinforcing agent for PHBV matrix. Different ester moieties from the CNCs were thereby produced through a green one-pot hydrolysis/Fisher esterification. Beyond the improved dispersion, the CNCs surface esterification affected the thermal and thermomechanical properties of PHBV. The results demonstrate that butyrate-modified CNCs, mimicking the PHBV chemical structure, brought a considerable improvement toward the CNCs/matrix interface, leading to an enhancement of the PHBV thermomechanical properties via a more efficient stress transfer, especially above its glass transition.

Multifunctionality of structural nanohybrids: the crucial role of carbon nanotube covalent and non-covalent functionalization in enabling high thermal, mechanical and self-healing performance.

This study proposes new kinds of functionalization procedures able to preserve specific properties of carbon nanotubes (CNTs) and to improve compatibility with the epoxy matrix. Through a covalent approach, for the first time, CNTs are functionalized with the same hardener agent, 4,4'-diaminodiphenyl sulfone, employed to solidify the epoxy matrix and capable to fulfill mechanical requirements of industrial structural resins. The same CNTs are non-covalently modified through the polymer wrapping mechanism with benzoxazine (Bz) terminated polydimethylsiloxane (PDMS). The comparison between electrical and mechanical properties of the nanocomposites highlights the success of the non-covalent functionalization in determining an increase in the glass transition temperature (Tg) and in better preserving the unfunctionalized CNT electrical conductivity. Besides, tunneling atomic force microscopy (TUNA), powerful to catch ultra-low currents, has been used for revealing the morphology on nanoscale domains and detecting the conductivity on the same location of CNT/epoxy resins. No electrical contacts to the grounds have been used for the TUNA analysis; a procedure that does not alter the results on the interface domains which experience contact areas with strong differences in their properties. The effectiveness of performed CNT functionalizations as a route to impart self-healing efficiency to the resin formulations has also been proved.

An Investigation of the Accuracy of EC5 and 5TE Capacitance Sensors for Soil Moisture Monitoring in Urban Soils-Laboratory and Field Calibration.

Recently, emphasis has been placed on finding a reliable estimation of soil water content. In this study, two capacitance sensors EC5 and 5TE (METER Group) were utilized. These sensors provide many benefits relative to other sensors in that they are cost-effective and very economical regarding energy use, operate at a high measurement frequency of 70 MHz, and are dedicated to measuring at a small volume because of their small size. This makes them suitable for the context of use in this research, which consists of multiple sustainable drainage systems SuDS. Several studies have evaluated these two types of sensor but not for urban soils with specific characteristics. In addition, results from the literature are divergent and the published calibration data are limited. Therefore, an in-depth investigation of their accuracy is assessed in this paper. At first, the literature's existing procedures and methods were examined. The sensor-to-sensor variability, as well as repeatability, were tested in soil and solutions. Additionally, a field calibration method was conducted to estimate the effects of soil texture on sensors readings. Two laboratory calibration methods having different principles were also applied, compared to each other and to the field calibration as well. Results revealed weak sensor-to-sensor variability (coefficient of variation up to 15% in soil) and also good repeatability (0.1%), for both sensors. A soil-specific calibration equation has improved the estimation of the volumetric water content. In case of soil having high field bulk density, the undisturbed soil calibration method described and proposed in this paper gives promising results. The latter method yields a volumetric water content (VWC) prediction accuracy of 0.025 m3∙m-3 on a sandy loam soil. This paper presents a large knowledge of capacitance sensors measurement technique as well as their calibration procedures and methods. Limitations of existing procedures have been identified and key elements for selecting the appropriate one are suggested. Derived calibration equations have also been provided for three urban soils with different particle size distribution, ranging from sandy loam to silt loam. Accurate monitoring of soil moisture content in urban soils is thus achievable.

Philips Intellivue NMT module: precision and performance improvements to meet the clinical requirements of neuromuscular block management.

The variability or inaccuracy of acceleromyographic measurements could interfere with the interpretation of the train-of-four (TOF) ratio during neuromuscular block (NMB) recovery. This study evaluated the precision and performance of the Philips Intellivue NMT module (NMT) before (part 1) and after (part 2) several technical upgrades (i.e., firmware upgrade, new cable, and hand adapter) that were recently available. Two cohorts of 30 patients who were scheduled to undergo rhino/septoplasty under general anesthesia were included in the study. TOF ratios were recorded simultaneously every 15 s on both hands with the NMT and a TOF-Watch SX installed inside a SL TOF-Tube (TWX). Before rocuronium was administered and once final responses were stabilized, the average of the four successive measurements that determined the baselines and repeatability coefficients were compared using a z test. Simultaneous measurements were recorded at different NMB stages: onset, depth of NMB after intubation, when TWX recovered TOF count 2, TOF ratios 0.5 and 0.9, and when NMT recovered TOF ratio 0.9. The results were compared using a Student t test; p < 0.05 was considered significant. The NMT repeatability coefficients obtained in part 1 were significantly higher than with the TWX, they were significantly lower in part 2. Initially, the NMT significantly overestimated NMB recovery at every stage. Conversely, in the second part of the study, no difference reached statistical significance. With the recent upgrades and the new hand adapter, the NMT provided similar results compared with the TWX, Their implementation should be recommended in clinical practice.

In Depth Analysis of Photovoltaic Performance of Chlorophyll Derivative-Based "All Solid-State" Dye-Sensitized Solar Cells.

Chlorophyll a derivatives were integrated in "all solid-state" dye sensitized solar cells (DSSCs) with a mesoporous TiO2 electrode and 2',2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene as the hole-transport material. Despite modest power conversion efficiencies (PCEs) between 0.26% and 0.55% achieved for these chlorin dyes, a systematic investigation was carried out in order to elucidate their main limitations. To provide a comprehensive understanding of the parameters (structure, nature of the anchoring group, adsorption …) and their relationship with the PCEs, density functional theory (DFT) calculations, optical and photovoltaic studies and electron paramagnetic resonance analysis exploiting the 4-carboxy-TEMPO spin probe were combined. The recombination kinetics, the frontier molecular orbitals of these DSSCs and the adsorption efficiency onto the TiO2 surface were found to be the key parameters that govern their photovoltaic response.

Modification of Poly(ethylene 2,5-furandicarboxylate) with Biobased 1,5-Pentanediol: Significantly Toughened Copolyesters Retaining High Tensile Strength and O2 Barrier Property.

Poly(ethylene 2,5-furandicarboxylate) (PEF) is a biobased polyester characterized by high gas barrier properties as well as high tensile modulus and strength, but poor toughness. Toughening PEF without sacrificing its modulus, strength and gas barrier performance is a great challenge for PEF modification. In this study, high molecular weight random poly(ethylene- co-1,5-pentylene 2,5-furandicarboxylate)s (PEPeFs) were synthesized via melt copolycondensation of 2,5-furandicarboxylic acid (FDCA), ethylene glycol (EG) and 1,5-pentanediol (PeDO), a cheap, biobased and commercially available odd-carbon comonomer. The synthesized PEPeFs were characterized and assessed with intrinsic viscosity, ATR-FTIR, 1H NMR, DSC, TGA and tensile, impact and O2 permeation test. Mayo-Lewis equation with "reactivity ratio" of 3.78 for PeDO and 0.75 for EG could be used as an empirical equation to correlate the copolyester composition (ϕPeF) with monomer composition. PEPeFs proved nearly amorphous copolyesters having excellent thermal stability. Brittle-ductile transition was achieved at ϕPeF as low as 9 mol %. Increasing ϕPeF led to increase in elongation at break and notch impact strength and decrease in Tg, O2 barrier performance and tensile modulus and strength. However, in comparison with PEF, PEF-rich PEPeFs (ϕPeF 9-47%) not only showed greatly improved elongation at break (29-265% vs 4%) and enhanced impact strength (2.2-3.9 kJ/m2) but also retained very high Young's modulus (2.8-3.3 vs 3.3 GPa) and yielding strength (72-83 vs 82 MPa). Particularly, when compared with bottle-grade PET, PE82Pe18F possesses equal Tg (ca. 75 °C) and comparable elongation at break (ca. 115%), but greatly improved yielding strength (83 MPa) and O2 gas barrier property (4.8 times). As modified PEF materials possessing superior thermo-mechanical and O2 gas barrier properties, these integrally biobased copolyesters may find practical applications in eco-packaging and other fields.

Photoactive Boron-Nitrogen-Carbon Hybrids: From Azo-borazines to Polymeric Materials.

In this paper, we describe synthetic routes for preparing a novel switchable BNC-based chromophore, composed of a borazine core peripherally functionalized with azobenzene moieties. Capitalizing on the Pd-catalyzed Suzuki cross-coupling reaction between a tris-triflate borazine and an organoboron azobenzene derivative, a photoswtichable azo-borazine derivative was successfully prepared. The molecule showed reversible E/Z photoisomerization upon irradiation at the maximum of the intense π-π* absorption feature (360 nm). X-ray crystallographic investigations revealed a nonplanar orientation of the three azobenzene moieties and the trans configuration of the -N═N- bonds. Building on the synthetic versatility of the borazine-azobenzene derivative, we used this photoactive scaffold to engineer soluble BN-doped polythiophene polymers. Photophysical characterization performed in solvents of different polarity suggested that the polymer undergoes intramolecular charge transfer (ICT).

Cyclosporine before PCI in Patients with Acute Myocardial Infarction.

BACKGROUND: Experimental and clinical evidence suggests that cyclosporine may attenuate reperfusion injury and reduce myocardial infarct size. We aimed to test whether cyclosporine would improve clinical outcomes and prevent adverse left ventricular remodeling. METHODS: In a multicenter, double-blind, randomized trial, we assigned 970 patients with an acute anterior ST-segment elevation myocardial infarction (STEMI) who were undergoing percutaneous coronary intervention (PCI) within 12 hours after symptom onset and who had complete occlusion of the culprit coronary artery to receive a bolus injection of cyclosporine (administered intravenously at a dose of 2.5 mg per kilogram of body weight) or matching placebo before coronary recanalization. The primary outcome was a composite of death from any cause, worsening of heart failure during the initial hospitalization, rehospitalization for heart failure, or adverse left ventricular remodeling at 1 year. Adverse left ventricular remodeling was defined as an increase of 15% or more in the left ventricular end-diastolic volume. RESULTS: A total of 395 patients in the cyclosporine group and 396 in the placebo group received the assigned study drug and had data that could be evaluated for the primary outcome at 1 year. The rate of the primary outcome was 59.0% in the cyclosporine group and 58.1% in the control group (odds ratio, 1.04; 95% confidence interval [CI], 0.78 to 1.39; P=0.77). Cyclosporine did not reduce the incidence of the separate clinical components of the primary outcome or other events, including recurrent infarction, unstable angina, and stroke. No significant difference in the safety profile was observed between the two treatment groups. CONCLUSIONS: In patients with anterior STEMI who had been referred for primary PCI, intravenous cyclosporine did not result in better clinical outcomes than those with placebo and did not prevent adverse left ventricular remodeling at 1 year. (Funded by the French Ministry of Health and NeuroVive Pharmaceutical; CIRCUS ClinicalTrials.gov number, NCT01502774; EudraCT number, 2009-013713-99.).

Correction to: Sea urchin growth dynamics at microstructural length scale revealed by Mn-labeling and cathodoluminescence imaging.

[This corrects the article DOI: 10.1186/s12983-017-0227-8.].

Processing of PVDF-based electroactive/ferroelectric films: importance of PMMA and cooling rate from the melt state on the crystallization of PVDF beta-crystals.

Poly(vinylidene difluoride) (PVDF) displays attractive ferroelectric/piezoelectric properties and its polar ß-crystals are specifically targeted for achieving electroactive applications. However, their direct crystallization from the melt state represents a challenging task that has never been addressed using melt-state processes. The use of poly(methyl methacrylate) (PMMA) is herein investigated to promote the PVDF polar ß-phase using melt-blending and extrusion-calendering technologies. The presence of the ß-phase is here confirmed by ATR-FTIR and WAXS experiments with blends at a PMMA content as low as 5 wt%. The key role of PMMA for the ß-phase crystallization from the melt state was unambiguously highlighted with the help of Flash DSC experiments in non-isothermal cooling mode from the melt state. PMMA is able to efficiently shift the α-to-ß crystal transition to lower cooling rates (>100-200 °C s-1), making the achievement of the PVDF polar ß-phase for these blends compatible with conventional processing tools. A crystal phase diagram is proposed for the PVDF/PMMA blends to highlight the dual effects of both PMMA and cooling rate on the PVDF crystallization during melt-processing. Ferroelectric properties were even observed for the blends containing PMMA up to 10 wt% with the highest remanent polarization obtained at 5 wt% PMMA. After 10 wt% PMMA, a progressive transition from ferroelectric to pseudo-linear dielectric behavior is observed more likely due to the presence of PMMA in the interlamellar amorphous phase of the polar PVDF spherulites as shown by SAXS experiments. In this work, we successfully demonstrated that PMMA plays a key role in the crystallization of PVDF polar crystals from the melt state, enabling large-scale and continuous extrusion processing of PVDF-based materials with attractive dielectric properties for sensing and harvesting applications.

Free-Radical-Induced Grafting from Plasma Polymer Surfaces.

With the advances in science and engineering in the second part of the 20th century, emerging plasma-based technologies continuously find increasing applications in the domain of polymer chemistry, among others. Plasma technologies are predominantly used in two different ways: for the treatment of polymer substrates by a reactive or inert gas aiming at a specific surface functionalization or for the synthesis of a plasma polymer with a unique set of properties from an organic or mixed organic-inorganic precursor. Plasma polymer films (PPFs), often deposited by plasma-enhanced chemical vapor deposition (PECVD), currently attract a great deal of attention. Such films are widely used in various fields for the coating of solid substrates, including membranes, semiconductors, metals, textiles, and polymers, because of a combination of interesting properties such as excellent adhesion, highly cross-linked structures, and the possibility of tuning properties by simply varying the precursor and/or the synthesis parameters. Among the many appealing features of plasma-synthesized and -treated polymers, a highly reactive surface, rich in free radicals arising from deposition/treatment specifics, offers a particular advantage. When handled carefully, these reactive free radicals open doors to the controllable surface functionalization of materials without affecting their bulk properties. The goal of this review is to illustrate the increasing application of plasma-based technologies for tuning the surface properties of polymers, principally through free-radical chemistry.

Dynamic Iminoboronate-Based Boroxine Chemistry for the Design of Ambient Humidity-Sensitive Self-Healing Polymers.

Developing intrinsic self-healing polymeric materials is of great interest nowadays to extend material lifetime and/or prevent the replacement of damaged pieces. Spontaneously humidity-sensitive healable polymer network built around dynamic covalent B-O bonds was templated by using iminoboronate-based boroxine derivatives. Taking advantage of the dynamic boroxine/boronic acid equilibrium and iminoboronate chemistry, it is possible to construct polymeric materials able to self-heal without requiring any energy-demanding external activation. Interestingly, this novel family of iminoboronate adduct-based materials can be readily produced by a relatively simple and straightforward synthesis between boronic acid and diamine-based compounds, paving the way to coatings that are self-healable at ambient humidity.

Sea urchin growth dynamics at microstructural length scale revealed by Mn-labeling and cathodoluminescence imaging.

BACKGROUND: Fluorochrome staining is among the most widely used techniques to study growth dynamics of echinoderms. However, it fails to detect fine-scale increments because produced marks are commonly diffusely distributed within the skeleton. In this paper we investigated the potential of trace element (manganese) labeling and subsequent cathodoluminescence (CL) imaging in fine-scale growth studies of echinoderms. RESULTS: Three species of sea urchins (Paracentrotus lividus, Echinometra sp. and Prionocidaris baculosa) were incubated for different periods of time in seawater enriched in different Mn2+ concentrations (1 mg/L; 3 mg/L; 61.6 mg/L). Labeling with low Mn2+ concentrations (at 1 mg/L and 3 mg/L) had no effect on behavior, growth and survival of sea urchins in contrast to the high Mn2+ dosage (at 61.6 mg/L) that resulted in lack of skeleton growth. Under CL, manganese produced clearly visible luminescent growth fronts in these specimens (observed in sectioned skeletal parts), which allowed for a determination of the average extension rates and provided direct insights into the morphogenesis of different types of ossicles. The three species tend to follow the same patterns of growth. Spine growth starts with the formation of microspines which are simultaneously becoming reinforced by addition of thickening layers. Spine septa develop via deposition of porous stereom that is rapidly (within less than 2 days) filled by secondary calcite. Development of the inner cortex in cidaroids begins with the formation of microspines which grow at ~3.5 µm/day. Later on, deposition of the outer polycrystalline cortex with spinules and protuberances proceeds at ~12 µm/day. The growth of tooth can be rapid (up to ~1.8 mm/day) and starts with the formation of primary plates (pp) in plumula. Later on, during the further growth of pp in aboral and lateral directions, secondary extensions develop inside (in chronological order: lamellae, needles, secondary plate, prisms and carinar processes), which are increasingly being solidified towards the incisal end. Interradial growth in the ambital interambulacral test plates exceeds meridional growth and inner thickening. CONCLUSIONS: Mn2+ labeling coupled with CL imaging is a promising, low-cost and easily applicable method to study growth dynamics of echinoderms at the micro-length scale. The method allowed us to evaluate and refine models of echinoid skeleton morphogenesis.