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The study of the structure and mechanical properties of complex fluid interfaces has gained increasing interest in recent decades as a result of its significant scientific relevance to the understanding of biological systems, drug development, and industrial applications. The in situ combination of molecular-level structural measurements with the assessment of dynamical (rheological) properties is particularly valuable, as comparing measurements conducted on separate samples under challenging-to-reproduce experimental conditions can be problematic. In this work, we present a new sample environment at the FIGARO instrument, the horizontal neutron reflectometer at the Institut Laue-Langevin, which includes an interfacial shear rheometer operating in the Double Wall-Ring (DWR) geometry, compatible with commercial rotational rheometers. This innovative setup enables simultaneous structural (neutron reflectometry) and dynamical (shear interfacial rheology) measurements on the same sample.

Understanding the formation of carbonyl sulfide (OCS) in interstellar ices is key to constrain the sulfur chemistry in the interstellar medium (ISM), since it is the only ice S-bearing molecule securely detected thus far. Two general pathways for OCS formation have been proposed: sulfurization of CO (CO+S) and oxidation of CS (CS+O), but their relative contribution in interstellar ices remains unconstrained. We have evaluated the contribution of both pathways to OCS formation upon energetic processing in isotopically-labeled CO2:CS2 and CO:CS2 ice samples at 7-50 K. Our results indicated that formation of OCS through the CS+O pathway was more favorable than through the CO+S pathway, as previously suggested by theoretical calculations. In addition, its relative contribution increased at higher temperatures. Therefore, this pathway could play a role in the ice formation of OCS, especially in warm regions where CO is expected to be preferentially in the gas phase. At the same time, we have explored the chemistry of CS2-bearing, CO2-, CO-, and also H2O-rich ices, that could be relevant to the sulfur interstellar chemistry. We observed formation of a variety of S-bearing products in addition to OCS, including SO2, C3S2, and S2. However, a significant fraction of sulfur was not detected at the end of the experiments, and could be locked in long, undetectable sulfur allotropes, one of the potential carriers of the missing sulfur in the dense ISM.

The increase in the demand for eXtended Reality (XR)/Virtual Reality (VR) services in the recent years, poses a great challenge for Wi-Fi networks to maintain the strict latency requirements. In VR over Wi-Fi, latency is a significant issue. In fact, VR users expect instantaneous responses to their interactions, and any noticeable delay can disrupt user experience. Such disruptions can cause motion sickness, and users might end up quitting the service. Differentiating interactive VR traffic from Non-VR traffic within a Wi-Fi network can aim to decrease latency for VR users and improve Wi-Fi Quality of Service (QoS) with giving priority to VR users in the access point (AP) and efficiently handle VR traffic. In this paper, we propose a machine learning-based approach for identifying interactive VR traffic in a Cloud-Edge VR scenario. The correlation between downlink and uplink is crucial in our study. First, we extract features from single-user traffic characteristics and then, we compare six common classification techniques (i.e., Logistic Regression, Support Vector Machines, k-Nearest Neighbors, Decision Trees, Random Forest, and Naive Bayes). For each classifier, a process of hyperparameter tuning and feature selection, namely permutation importance is applied. The model created is evaluated using datasets generated by different VR applications, including both single and multi-user cases. Then, a Wi-Fi network simulator is used to analyze the VR traffic identification and prioritization QoS improvements. Our simulation results show that we successfully reduce VR traffic delays by a factor of 4.2x compared to scenarios without prioritization, while incurring only a 2.3x increase in delay for background (BG) traffic related to Non-VR services., Comment: 19 pages, 6 figures

The reservoir of sulfur accounting for sulfur depletion in the gas of dense clouds and circumstellar regions is still unclear. One possibility is the formation of sulfur chains, which would be difficult to detect by spectroscopic techniques. This work explores the formation of sulfur chains experimentally, both in pure H$_2$S ice samples and in H$_2$O:H$_2$S ice mixtures. An ultra-high vacuum chamber, ISAC, eqquipped with FTIR and QMS, was used for the experiments. Our results show that the formation of H$_2$S$_x$ species is efficient, not only in pure H$_2$S ice samples, but also in water-rich ice samples. Large sulfur chains are formed more efficiently at low temperatures ($\approx$10 K), while high temperatures ($\approx$50 K) favour the formation of short sulfur chains. Mass spectra of H$_2$S$_x$, x~=~2-6, species are presented for the first time. Their analysis suggests that H$_2$S$_x$ species are favoured in comparison with S$_x$ chains. Nevertheless, the detection of several S$_x^+$ fragments at high temperatures in H$_2$S:H$_2$O ice mixtures suggests the presence of S$_8$ in the irradiated ice samples, which could sublimate from 260~K. ROSINA instrument data from the cometary Rosetta mission detected mass-to-charge ratios 96 and 128. Comparing these detections with our experiments, we propose two alternatives: 1) H$_2$S$_4$ and H$_2$S$_5$ to be responsible of those S$_3^+$ and S$_4^+$ cations, respectively, or 2) S$_8$ species, sublimating and being fragmented in the mass spectrometer. If S$_8$ is the parent molecule, then S$_5^+$ and S$_6^+$ cations could be also detected in future missions by broadening the mass spectrometer range.

Extended Reality (XR) has stringent throughput and delay requirements that are hard to meet with current wireless technologies. Missing these requirements can lead to worsened picture quality, perceived lag between user input and corresponding output, and even dizziness for the end user. In this paper, we study the capability of upcoming Wi-Fi 7, and its novel support for Multi-Link Operation (MLO), to cope with these tight requirements. Our study is based on simulation results extracted from an MLO-compliant simulator that realistically reproduces VR traffic. Results show that MLO can sustain VR applications. By jointly using multiple links with independent channel access procedures, MLO can reduce the overall delay, which is especially useful in the uplink, as it has more stringent requirements than the downlink, and is instrumental in delivering the expected performance. We show that using MLO can allow more users per network than an equivalent number of links using SLO. We also show that while maintaining the same overall bandwidth, a higher number of MLO links with narrow channels leads to lower delays than a lower number of links with wider channels.

The surfaces of icy moons are primarily composed of water ice that can be mixed with other compounds, such as carbon dioxide. The carbon dioxide (CO$_2)$ stretching fundamental band observed on Europa and Ganymede appears to be a combination of several bands that are shifting location from one moon to another. We investigate the cause of the observed shift in the CO$_2$ stretching absorption band experimentally. We also explore the spectral behaviour of CO$_2$ ice by varying the temperature and concentration.} %H$_2$O:CO$_2$ deposition ratios. We analyzed pure CO$_2$ ice and ice mixtures deposited at 10 K under ultra-high vacuum conditions using Fourier-transform infrared (FTIR) spectroscopy and temperature programmed desorption (TPD) experiments. Laboratory ice spectra were compared to JWST observation of Europa's and Ganymede's leading hemispheres. The simulated IR spectra were calculated using density functional theory (DFT) methods, exploring the effect of porosity in CO$_2$ ice. Pure CO$_2$ and CO$_2$-water ice show distinct spectral changes and desorption behaviours at different temperatures, revealing intricate CO$_2$ and H$_2$O interactions. The number of discernible peaks increases from two in pure CO$_2$ to three in CO$_2$-water mixtures., Comment: Accepted for publication in Astronomy & Astrophysics

Automated Machine Learning (AutoML) has become increasingly popular in recent years due to its ability to reduce the amount of time and expertise required to design and develop machine learning systems. This is very important for the practice of machine learning, as it allows building strong baselines quickly, improving the efficiency of the data scientists, and reducing the time to production. However, despite the advantages of AutoML, it faces several challenges, such as defining the solutions space and exploring it efficiently. Recently, some approaches have been shown to be able to do it using tree-based search algorithms and context-free grammars. In particular, GramML presents a model-free reinforcement learning approach that leverages pipeline configuration grammars and operates using Monte Carlo tree search. However, one of the limitations of GramML is that it uses default hyperparameters, limiting the search problem to finding optimal pipeline structures for the available data preprocessors and models. In this work, we propose an extension to GramML that supports larger search spaces including hyperparameter search. We evaluated the approach using an OpenML benchmark and found significant improvements compared to other state-of-the-art techniques.

Using the recently developed multistate mapping approach to surface hopping (multistate MASH) method combined with SA(3)-CASSCF(12,12)/aug-cc-pVDZ electronic structure calculations, the gas-phase isotropic ultrafast electron diffraction (UED) of cyclobutanone is predicted and analyzed. After excitation into the n-3s Rydberg state (S$_2$), cyclobutanone can relax through two S$_2$/S$_1$ conical intersections, one characterized by compression of the \ce{CO} bond, the other by dissociation of the $\mathrm{\alpha}$-CC bond. Subsequent transfer into the ground state (S$_0$) is then achieved via two additional S$_1$/S$_0$ conical intersections that lead to three reaction pathways: $\mathrm{\alpha}$ ring-opening, ethene/ketene production, and \ce{CO} liberation. The isotropic gas-phase UED signal is predicted from the multistate MASH simulations, allowing for a direct comparison to experimental data. This work, which is a contribution to the cyclobutanone prediction challenge, facilitates the identification of the main photoproducts in the UED signal and thereby emphasizes the importance of dynamics simulations for the interpretation of ultrafast experiments., Comment: Cyclobutanone prediction challenge in Journal of Chemical Physics

Virtual Reality (VR) streaming enables end-users to seamlessly immerse themselves in interactive virtual environments using even low-end devices. However, the quality of the VR experience heavily relies on Wireless Fidelity (Wi-Fi) performance, since it serves as the last hop in the network chain. Our study delves into the intricate interplay between Wi-Fi and VR traffic, drawing upon empirical data and leveraging a Wi-Fi simulator. In this work, we further evaluate Wi-Fi's suitability for VR streaming in terms of the Quality of Service (QoS) it provides. In particular, we employ Unity Render Streaming to remotely stream real-time VR gaming content over Wi-Fi 6 using Web Real-Time Communication (WebRTC), considering a server physically located at the network's edge, near the end user. Our findings demonstrate the system's sustained network performance, showcasing minimal round-trip time (RTT) and jitter at 60 and 90 frames per second (fps). In addition, we uncover the characteristics and patterns of the generated traffic streams, unveiling a distinctive video transmission approach inherent to WebRTC-based services: the systematic packetization of video frames (VFs) and their transmission in discrete batches at regular intervals, regardless of the targeted frame rate. This interval-based transmission strategy maintains consistent video packet delays across video frame rates but leads to increased Wi-Fi airtime consumption. Our results demonstrate that shortening the interval between batches is advantageous, as it enhances Wi-Fi efficiency and reduces delays in delivering complete frames., Comment: 17 pages, 26 figures

Impregnation treatments are one of the alternatives to protect concrete-based building and monuments from weathering degradation. However, it is important to consider the chemical compatibility of the reaction products with the building material. The impregnation product studied here consists of a silica oligomer able to polymerize, by a simple sol-gel process, inside the pore structure of concrete. In this work, we investigate the ability of this impregnation treatment to produce C-S-H gel in contact with cement paste. A complete characterization of the reaction products demonstrated that the silanol groups from silica oligomers react with the portlandite present in the cement paste generating a material with the chemical, structural and morphological features of CS-H gel. Simultaneously, the 29Si NMR results indicate that the Si-O units are incorporated into the existing C-S-H, increasing its chain length. These results open the way for a simple concrete structures repairing procedure., Comment: 15 pages, 11 figures, 1 table, 44 references. Gold Open Access publication

Acetic acid (CH3COOH) was detected in the gas toward interstellar clouds, hot cores, protostars and comets. Its formation in ice mantles was proposed and acetic acid awaits detection in the infrared spectra of the ice as most other COMs except methanol. The thermal annealing and UV-irradiation of acetic acid in the ice was simulated experimentally in this work under astrophysically relevant conditions. The experiments were performed under ultra-high vacuum conditions. An ice layer was formed by vapor deposition onto a cold substrate, and was warmed up or exposed to UV photons. The ice was monitored by infrared spectroscopy while the molecules desorbing to the gas phase were measured using a quadrupole mass spectrometer. The transformation of the CH3COOH monomers to cyclic dimers occurs at 120 K and the crystal form composed of chain polymers was observed above 160 K during warm-up of the ice. Ice sublimation proceeds at 189 K in our experiments. Upon UV-irradiation simpler species and radicals are formed, which lead to a residue made of complex molecules after warm-up to room temperature. The possible formation of oxalic acid needs to be confirmed. The photodestruction of acetic acid molecules is reduced when mixed with water in the ice. This work may serve to search for the acetic acid photoproducts in lines of sight where this species is detected. A comparison of the reported laboratory infrared spectra with current JWST observations allows to detect or set upper imits on the CH3COOH abundances in interstellar and circumstellar ice mantles., Comment: Accepted to MNRAS

LiNbO3 is a distinguished multifunctional material where ferroelectric domain engineering is of paramount importance. This degree of freedom of the spontaneous polarization remarkably enhances the applicability of LiNbO3, for instance in nonlinear photonics. However, conventional electrical poling suffers from several drawbacks. Namely, the lithographic patterning of electrodes is cumbersome and expensive, and the spatial resolution is constrained. In this work, we report the first method for all-optical domain inversion of LiNbO3 crystals using continuous-wave visible light. While we mainly focus on iron-doped LiNbO3, the applicability of the method is also showcased in undoped congruent LiNbO3. The technique is outstandingly simple, low-cost and readily accessible. It relies on ubiquitous elements: a light source with low/moderate power, basic optics and a conductive surrounding medium, e.g. water. Light-induced domain inversion is unequivocally demonstrated and characterized by combination of several experimental techniques: pyroelectric trapping of charged microparticles, selective chemical etching, surface topography profilometry, scanning electron microscopy and 3D Cerenkov microscopy. The influence of light intensity, exposure time, laser spot size and surrounding medium is thoroughly studied. Overall, our all-optical method offers straightforward implementation of LiNbO3 ferroelectric domain engineering, potentially sparking new research endeavors aimed at novel optoelectronic applications of photovoltaic LiNbO3 platforms.

Monitoring wellbeing and stress is one of the problems covered by ambient intelligence, as stress is a significant cause of human illnesses directly affecting our emotional state. The primary aim was to propose a deliberation architecture for an ambient intelligence healthcare application. The architecture provides a plan for comforting stressed seniors suffering from negative emotions in an assisted living home and executes the plan considering the environment's dynamic nature. Literature was reviewed to identify the convergence between deliberation and ambient intelligence and the latter's latest healthcare trends. A deliberation function was designed to achieve context-aware dynamic human-robot interaction, perception, planning capabilities, reactivity, and context-awareness with regard to the environment. A number of experimental case studies in a simulated assisted living home scenario were conducted to demonstrate the approach's behavior and validity. The proposed methods were validated to show classification accuracy. The validation showed that the deliberation function has effectively achieved its deliberative objectives.

The presence of methanol among the common ice components in interstellar clouds and protostellar envelopes has been confirmed by the James Webb Space Telescope. Methanol is often detected in the gas phase toward lines of sight shielded from UV radiation. We measured the volumetric density of methanol ice, grown under simulated interstellar conditions, and the infrared spectroscopy at different deposition temperatures and during the warm-up. The IR band strengths are provided and the experimental spectra are compared to those computed with a model. The transition from amorphous to crystalline methanol ice was also explored. Finally, we propose new observations of methanol ice at high resolution to probe the methanol ice structure., Comment: 11 pages, 11 figures

In this article, we investigate the real-world capability of the multi-link operation (MLO) framework -- one of the key MAC-layer features included in the IEEE 802.11be amendment -- by using a large dataset containing 5 GHz spectrum occupancy measurements on multiple channels. Our results show that when both available links are often busy, as is the case in ultra-dense and crowded scenarios, MLO attains the highest throughput gains over single-link operation (SLO) since it is able to leverage multiple intermittent transmission opportunities. As for latency, if the two links exhibit statistically the same level of occupancy, MLO can outperform SLO by one order of magnitude. In contrast, in asymmetrically occupied links, MLO can sometimes be detrimental and even increase latency. We study this somewhat unexpected phenomenon, and find its origins to be packets suboptimally mapped to either link before carrying out the backoff, with the latter likely to be interrupted on the busier link. We cross validate our study with real-time traffic generated by a cloud gaming application and quantify MLO's benefits for latency-sensitive applications.

What will Wi-Fi 8 be? Driven by the strict requirements of emerging applications, next-generation Wi-Fi is set to prioritize Ultra High Reliability (UHR) above all. In this paper, we explore the journey towards IEEE 802.11bn UHR, the amendment that will form the basis of Wi-Fi 8. We first present new use cases calling for further Wi-Fi evolution and associated standardization, certification, and spectrum allocation efforts. We then introduce a selection of the main disruptive features envisioned for Wi-Fi 8 and their associated research challenges, resulting from the outcome of the UHR Study Group. Among those, we focus on multi access point coordination and demonstrate that it could build upon 802.11be multi-link operation to make UHR a reality in Wi-Fi 8.

Multi-link Operation (MLO), arguably the most disruptive feature introduced in IEEE 802.11be, will cater for delay-sensitive applications by using multiple radio interfaces concurrently. In this paper, we analyze the delay distribution of MLO under non-saturated traffic. Our results show that upgrading from legacy single-link to MLO successfully contains the $95$th percentile delay as the traffic load increases, but also that adding extra interfaces yields rapidly diminishing gains. Further experiments we conduct on Google Stadia traces, accounting for realistic traffic with batch arrivals, confirm the insights stemming from our theoretical analysis, vouching for MLO to support high-resolution real-time video with a controlled delay.

The motivation to study experimentally CO ice under mimicked interstellar conditions is supported by the large CO gas abundances and ubiquitous presence of CO in icy grain mantles. Upon irradiation in its pure ice form, this highly stable species presents a limited ion and photon-induced chemistry, and an efficient non-thermal desorption. Using infrared spectroscopy, single laser interference, and quadrupole mass spectrometry during CO ice deposition, the CO ice density was estimated as a function of deposition temperature. Only minor variations in the density were found. The proposed methodology can be used to obtain the density of other ice components at various deposition temperatures provided that this value of the density is known for one of these temperatures, which is typically the temperature corresponding to the crystalline form. The apparent tendency of the CO ice density to decrease at deposition temperatures below 14 K is in line with recently published colorimetric measurements. This work allowed to revisit the value of the infrared band strength needed for calculation of the CO ice column density in infrared observations, $8.7 \times 10^{-18} ~ {\rm cm ~ molecule}^{-1}$ at 20 K deposition temperature., Comment: 21 pages, 9 figures

Will Wi-Fi 7, conceived to support extremely high throughput, also deliver consistently low delay? The best hope seems to lie in allowing next-generation devices to access multiple channels via multi-link operation (MLO). In this paper, we aim to advance the understanding of MLO, placing the spotlight on its packet delay performance. We show that MLO devices can take advantage of multiple contention-free links to significantly reduce their transmission time, but also that they can occasionally starve one another and surprisingly incur a higher delay than that of a well planned legacy single link operation. We next examine and explain this anomaly, also putting forth practical workarounds to circumvent it. We conclude by pointing to other disruptive features that, if successfully paired with MLO, can usher in exciting and unprecedented opportunities for Wi-Fi 8.

Wi-Fi 7 is already in the making, and Multi-Link Operation (MLO) is one of the main features proposed in its correspondent IEEE 802.11be amendment. MLO will allow devices to coordinate multiple radio interfaces to access separate channels through a single association, aiming for improved throughput, network delay, and overall spectrum reuse efficiency. In this work, we study three reference scenarios to evaluate the performance of the two main MLO implementations -- Multi-Link Multi-Radio (MLMR) and Multi-Link Single-Radio (MLSR) -- , the interplay between multiple nodes employing them, and their coexistence with legacy Single-Link devices. Importantly, our results reveal that the potential of MLMR is mainly unleashed in isolated deployments or under unloaded network conditions. Instead, in medium- to high-load scenarios, MLSR may prove more effective in reducing the latency while guaranteeing fairness with contending Single-Link nodes.

Photovoltaic optoelectronic tweezers (PVOT) have been proven to be an efficient tool for the manipulation and massive assembly of micro/nano-objects. The technique relies on the strong electric fields produced by certain ferroelectric materials upon illumination due to the bulk photovoltaic effect (customarily LiNbO3:Fe). Despite the rapid development of PVOT and the achievement of high-quality 1D and 2D particle patterning, research efforts aimed at the fabrication of combinatorial structures made up of multiple types of particles have been scarce. Here, we have established the working principles of three different methods to tackle this pending challenge. To that end, dielectrophoresis and/or electrophoresis acting on neutral and charged particles respectively, have been suitably exploited. Simple mixed structures combining metallic and dielectric nanoparticles of different sizes have been successfully obtained. The results lay the groundwork for future fabrication of more complex combinatorial structures by PVOT, where micro/nanoparticles are the basic building blocks of miniaturized functional devices., Comment: 17 pages, 5 figures

The study of thermal properties of frozen salt solutions representative of ice layers in Jovian moons is crucial to support the JUpiter ICy moons Explorer (JUICE) (ESA) and Europa Clipper (NASA) missions, which will be launched in the upcoming years to make detailed observations of the giant gaseous planet Jupiter and three of its largest moons (Ganymede, Europa, and Callisto), due to the scarcity of experimental measurements. Therefore, we have conducted a set of experiments to measure and study the thermal conductivity of macroscopic frozen salt solutions of particular interest in these regions, including sodium chloride (NaCl), magnesium sulphate (MgSO$_4$), sodium sulphate (Na$_2$SO$_4$), and magnesium chloride (MgCl$_2$). Measurements were performed at atmospheric pressure and temperatures from 0 to -70$^{\circ}$C in a climatic chamber. Temperature and calorimetry were measured during the course of the experiments. An interesting side effect of these measurements is that they served to spot phase changes in the frozen salt solutions, even for very low salt concentrations. A small sample of the liquid salt-water solution was set aside for the calorimetry measurements. These experiments and the measurements of thermal conductivity and calorimetry will be valuable to constrain the chemical composition, physical state, and temperature of the icy crusts of Ganymede, Europa, and Callisto.

Will Multi-Link Operation (MLO) be able to improve the latency of Wi-Fi networks? MLO is one of the most disruptive MAC-layer techniques included in the IEEE 802.11be amendment. It allows a device to use multiple radios simultaneously and in a coordinated way, providing a new framework to improve the WLAN throughput and latency. In this paper, we investigate the potential latency benefits of MLO by using a large dataset containing 5 GHz spectrum occupancy measurements. Experimental results show that when the channels are symmetrically occupied, MLO can improve latency by one order of magnitude. In contrast, in asymmetrically occupied channels, MLO can sometimes be detrimental and increase latency. To address this case, we introduce Opportunistic Simultaneous Transmit and Receive (STR+) channel access and study its benefits.

Context. Sulfur is used as a tracer of the evolution from interstellar clouds to stellar systems. However, most of the expected sulfur in molecular clouds remains undetected. Sulfur disappears from the gas phase in two steps. One first depletion occurs during the translucent phase, reducing the gas phase sulfur by 7-40 times, while the following freeze-out step occurs in molecular clouds, reducing it by another order of magnitude. This long-standing dilemma awaits an explanation. Aims. The aim of this study is to understand under which form the missing sulfur is hiding in molecular clouds. Depletion onto dust grains is considered. Methods. Experimental simulations mimicking H2S ice UV-photoprocessing in molecular clouds were conducted. The ice was monitored using infrared spectroscopy and the desorbing molecules were measured by quadrupole mass spectrometry. Theoretical Monte Carlo simulations were performed for interpretation of the experimental results and extrapolation to astrophysical conditions. Results. H2S2 formation was observed during irradiation at 8 K. Molecules H2Sx with x > 2 were also identified and found to desorb during warm-up, along with S2 to S4 species. Larger Sx molecules up to S8 are refractory at room temperature and remained on the substrate forming a residue. Monte Carlo simulations were able to reproduce the molecules desorbing during warming up, and found that residues are chains or sulfur consisting of 6-7 atoms. Conclusions. We propose that S+ in translucent clouds contributes notoriously to S depletion in denser regions by forming long S-chains on dust in few times 10^4 years. We suggest that the S2 to S4 molecules observed in comets are not produced by fragmentation of these large chains. Instead, they probably come either from UV-photoprocessing of H2S-bearing ice produced in molecular clouds or from short S chains formed during the translucent cloud phase, Comment: Accepted to A&A

The study and applications of ferroelectric materials in the biomedical and biotechnological fields is a novel and very promising scientific area that spans roughly one decade. However, some groups have already provided experimental proof of very interesting biological modulation when living systems are exposed to different ferroelectrics and excitation mechanisms. These materials should offer several advantages in the field of bioelectricity, such as no need of an external electric power source or circuits, scalable size of the electroactive regions, flexible and reconfigurable virtual electrodes, or fully proved biocompatibility. In this focused review we provide the underlying physics of ferroelectric activity and a recount of the research reports already published, along with some tentative biophysical mechanisms that can explain the observed results. More specifically, we focused on the biological actions of domain ferroelectrics, and ferroelectrics excited by the bulk photovoltaic effect or the pyroelectric effect. It is our goal to provide a comprehensive account of the published material so far, and to set the stage for a vigorous expansion of the field, with envisioned applications that span from cell biology and signaling to cell and tissue regeneration, antitumoral action, or cell bioengineering to name a few., Comment: 39 pages, 10 figures, 3 tables, 127 references, publication year 2018

Hexamethylentetramine has drawn a lot of attention due to its potential to produce prebiotic species. This work aims to gain a better understanding in the chemical processes concerning methylamine under astrophysically relevant conditions. In particular, this work deeps into the formation of N-heterocycles in interstellar ice analogs exposed to UV radiation, which may lead to the formation of prebiotic species. Experimental simulations of interstellar ice analogs were carried out in ISAC. ISAC is an ultra-high vacuum chamber equipped with a cryostat, where gas and vapour species are frozen forming ice samples. Infrared and ultraviolet spectroscopy were used to monitor the solid phase, and quadrupole mass spectrometry served to measure the composition of the gas phase. The variety of species detected after UV irradiation of ices containing methylamine revealed the presence of 12 species which have been already detected in the ISM, being 4 of them typically classified as complex organic molecules: formamide (HCONH2), methyl cyanide (CH$_3$CN), CH$_3$NH and CH$_3$CHNH. Warming up of the irradiated CH$_3$NH$_2$-bearing ice samples lead to the formation of trimethylentriamine (TMT), a N-heterocycle precursor of HMT, and the subsequent synthesis of HMT at temperatures above 230 K.

This paper reports on how the FutureLearn Massive Open Online Course (MOOC) "Becoming a Better Teacher" was blended into English Language Teaching (ELT) university programmes in conjunction with telecollaboration. It discusses how the addition of a MOOC blend can enhance a telecollaborative exchange by adding to it increased opportunities for social collaborative interaction on a global scale. Blending MOOCs into English Teacher Education with Telecollaboration (BMELTET) fosters the students' reflection on online and blended learning and teaching to support their future teaching practice. The paper illustrates how participating students -- undergraduate ELT students from Spain and postgraduate ELT students studying in the UK -- participated in both synchronous and asynchronous exchanges on the MOOC content. The discussion will focus on how a holistic approach to the integration of technology into language teacher education programmes with a blend of formal and informal platforms can support students in reflecting on their beliefs. [For the complete volume, "New Educational Landscapes: Innovative Perspectives in Language Learning and Technology," see ED596359.]