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Porous organic polymers are versatile platforms, easily adaptable to a wide range of applications, from air filtering to energy devices. Their fabrication via vat photopolymerization enables them to control the geometry on a multiscale level, obtaining hierarchical porosity with enhanced surface-to-volume ratio. In this work, a photocurable ink based on 1,6 Hexanediol diacrylate and containing a high internal phase emulsion (HIPE) is presented, employing PLURONIC F-127 as a surfactant to generate stable micelles. Different parameters were studied to assess the effects on the morphology of the pores, the printability and the mechanical properties. The tests performed demonstrates that only water-in-oil emulsions were suitable for 3D printing. Afterwards, 3D complex porous objects were printed with a Digital Light Processing (DLP) system. Structures with large, interconnected, homogeneous porosity were fabricated with high printing precision (300 µm) and shape fidelity, due to the addition of a Radical Scavenger and a UV Absorber that improved the 3D printing process. The formulations were then used to build scaffolds with complex architecture to test its application as a filter for CO

B. parapertussis is a whooping cough etiological agent, whose incidence in the population has increased remarkably. Virulence factors involved in the bacterial infection, however, remain poorly investigated. We here studied the role of adenylate cyclase (CyaA), the main toxin of B. parapertussis, in the outcome of the bacterial interaction with macrophages. Our results showed that B. parapertussis CyaA intoxicates human macrophages, prevents bacterial phagocytosis and precludes phago-lysosomal fusion eventually promoting the bacterial survival to the encounter with these immune cells. Accordingly, we found that B. parapertussis CyaA induces the transcriptional downregulation of host genes encoding for antimicrobial peptides, proteins involved in bacterial intracellular killing, and the pro-inflammatory cytokine TNF-α, while induces the upregulation of the anti-inflammatory cytokine IL-10. Together with previous reports suggesting a protective role of B. parapertussis CyaA against neutrophils bactericidal activity, the results of this study suggest a central role of CyaA in B. parapertussis immune evasion and persistence.

The conversion of carbon dioxide into value-added products using sunlight, also called artificial photosynthesis, represents a remarkable and sustainable approach to store solar energy, transformin...

Inquilinus limosus is an emerging multi-resistant opportunistic pathogen documented mainly in cystic fibrosis patients. Infection with I. limosus is accompanied by either an acute respiratory exacerbation or a progressive loss of pulmonary function. This study examined the interaction of Inquilinus limosus with the bronquial human epithelial cell line 16HBE14o

The massive worldwide transition of the transport sector to electric vehicles has dramatically increased the demand for lithium. Lithium recovery by means of ion sieves or supramolecular chemistry has been extensively studied in recent years as a viable alternative approach to the most common extraction processes. Graphene oxide (GO) has also already been proven to be an excellent candidate for water treatment and other membrane related applications. Herein, a nanocomposite 12-crown-4-ether functionalized GO membrane for lithium recovery by means of pressure filtration is proposed. GO flakes were via carbodiimide esterification, then a polymeric binder was added to improve the mechanical properties. The membrane was then obtained and tested on a polymeric support in a dead-end pressure setup under nitrogen gas to speed up the lithium recovery. Morphological and physico-chemical characterizations were carried out using pristine GO and functionalized GO membranes for comparison with the nanocomposite. The lithium selectivity was proven by both the conductance and ICP mass measurements on different sets of feed and stripping solutions filtrated (LiCl/HCl and other chloride salts/HCl). The membrane proposed showed promising properties in low concentrated solutions (7 mgLi/L) with an average lithium uptake of 5 mgLi/g in under half an hour of filtration time.

Porous organic polymers are versatile platforms, easily adaptable to a wide range of applications, from air filtering to energy devices. Their fabrication via vat photopolymerization enables them to control the geometry on a multiscale level, obtaining hierarchical porosity with enhanced surface-to-volume ratio. In this work, a photocurable ink based on 1,6 Hexanediol diacrylate and containing a high internal phase emulsion (HIPE) is presented, employing PLURONIC F-127 as a surfactant to generate stable micelles. Different parameters were studied to assess the effects on the morphology of the pores, the printability and the mechanical properties. The tests performed demonstrates that only water-in-oil emulsions were suitable for 3D printing. Afterwards, 3D complex porous objects were printed with a Digital Light Processing (DLP) system. Structures with large, interconnected, homogeneous porosity were fabricated with high printing precision (300 µm) and shape fidelity, due to the addition of a Radical Scavenger and a UV Absorber that improved the 3D printing process. The formulations were then used to build scaffolds with complex architecture to test its application as a filter for CO2 absorption and trapping from environmental air. This was obtained by surface decoration with NaOH nanoparticles. Depending on the surface coverage, tested specimens demonstrated long-lasting absorption efficiency.

It is shown that the frequency dependence of the phenomenological parameters entering Langmuir kinetic equation describing the surface adsorption could be related to a random distribution of relaxation times. A theoretical model based on a generalization of Langmuir isotherm, taking into account a homogeneous distribution of relaxation times is proposed for supercapacitor modeling. Its theoretical predictions agree well with experimental data derived by the analysis of Lissajous figures describing the response of an electrochemical cell excited with a well defined frequency. According to our data, the effective desorption time is a rapidly decreasing function of the frequency of the applied signal, whereas the effective adsorption coefficient is an increasing function of it. The effective relaxation time is independent of the ionic concentration, whereas the effective adsorption coefficient strongly depends on this quantity. A large increase in the adsorption coefficient is reported, for the electrochemical cells with high surface area of the electrodes.

The growing interest in developing wearable energy storage devices requires the identification of suitable materials for the fabrication of their components. In this paper we report a new asymmetric fiber-shaped supercapacitor exploiting a composite of hematite and reduced graphene oxide aerogel obtained by a hydrothermal synthesis in presence of green extract as anode material and electrodeposited nanostructured MnOx as cathode. The three dimensional arrangement of the graphene flakes during the hydrothermal self-assembly process provides a highly conductive porous matrix with high surface area and, most importantly, a pores structure able to guarantee the rapid diffusion of the electrolyte ions and a fast electron transport. By simply modifying the hydrothermal recipe adding a dispersion of hematite nanoparticles, obtained using olive leaves extract as green surfactant, it is possible to obtain the decoration of the graphene network with the pseudocapacitive material. The resulting nanocomposite rGO/Fe2O3 aerogel exhibits excellent pseudocapacitive behaviour and it is used, in combination with MnOx nanostructured electrode, to fabricate a flexible fiber-shaped device exhibiting superior rate capability and bending stability. The use of a green surfactant during the synthesis opens up new avenues for the fabrication of environmentally friendly electrodes for wearable energy storage applications.

The electric responses of electrochemical capacitors produced with electrodes build up of reduced graphene oxide (rGO) deposited on Fluorine-doped tin oxide (FTO) coated glass have been experimentally investigated by cyclic voltammetry measurements. According to our experimental data, the parametric curve of the current in the circuit versus the external voltage is a continuous curve without discontinuity points respect to the inversion points of the external voltage. A few equivalent electric circuits able to reproduce the electric response of the capacitor are discussed. The dependence of the area delimited by the parametric cyclic voltammetry curve on the elements of the circuit is investigated. The possible evaluation of the effective capacitance of the capacitor by the numerical evaluation of the area delimited by the parametric curve is critically discussed and the limit of the procedure is underlined. A model based on the Poisson-Nernst-Planck theory with adsorbing electrodes is developed and used to fit the experimental voltammogram. The agreement between the theoretical model and the experimental data is good, indicating the importance of the adsorption phenomenon in the electric response of electrochemical capacitor to an external electric field.

In this paper a novel polymer-based platform is applied for the fabrication of an innovative two-electrodes self-powered device integrating energy harvesting and storage sections. A multifunctional polymeric layer, made of two poly(ethylene glycol)-based sections separated by a perfluorinated barrier, is obtained by oxygen-inhibited UV-light crosslinking procedure. For the energy harvesting section, one side of the polymeric layer is adapted to enable iodide/triiodide diffusion in a dye-sensitized solar cell (DSSC), while the other side empowers sodium/chloride ions diffusion and is used for on-board charge storage in an electrochemical double layer capacitor (EDLC). The resulting photocapacitor has a planar architecture appreciably simplified with respect to other recently proposed solutions and more easily exploitable in low power electronics. The measured photo-electrical conversion and storage total efficiency is 3.72% during photo-charge, which is a remarkable value for DSSC-EDLC harvesting-storage devices literature. The obtained high frequency discharge capability enlightens promising prospects for practical applications in low power portable electronics.

The ever-increasing amount of batteries used in today's society has led to an increase in the demand of lithium in the last few decades. While mining resources of this element have been steadily exploited and are rapidly depleting, water resources constitute an interesting reservoir just out of reach of current technologies. Several techniques are being explored and novel materials engineered. While evaporation is very time-consuming and has large footprints, ion sieves and supramolecular systems can be suitably tailored and even integrated into membrane and electrochemical techniques. This review gives a comprehensive overview of the available solutions to recover lithium from water resources both by passive and electrically enhanced techniques. Accordingly, this work aims to provide in a single document a rational comparison of outstanding strategies to remove lithium from aqueous sources. To this end, practical figures of merit of both main groups of techniques are provided. An absence of a common experimental protocol and the resulting variability of data and experimental methods are identified. The need for a shared methodology and a common agreement to report performance metrics are underlined.

Purpose of review An initial intracellular phase of usually extracellular bacterial pathogens displays an important strategy to hide from the host's immune system and antibiotics therapy. It helps the bacteria, including bacterial pathogens of airway diseases, to persist and eventually switch to a typical extracellular infection. Several infectious diseases of the lung are life-threatening and their control is impeded by intracellular persistence of pathogens. Thus, molecular adaptations of the pathogens to this niche but also the host's response and potential targets to interfere are of relevance. Here we discuss examples of historically considered extracellular pathogens of the respiratory airway where the intracellular survival and proliferation is well documented, including infections by Staphylococcus aureus, Bordetella pertussis, Haemophilus influenzae, Pseudomonas aeruginosa, and others. Recent findings Current studies focus on bacterial factors contributing to adhesion, iron acquisition, and intracellular survival as well as ways to target them for combatting the bacterial infections. Summary The investigation of common and specific mechanisms of pathogenesis and persistence of these bacteria in the host may contribute to future investigations and identifications of relevant factors and/or bacterial mechanisms to be blocked to treat or improve prevention strategies.

Neural probes are in vivo brain-invasive devices that record and manipulate neural circuits using electricity, light, or drugs. The capability to shine distinct wavelengths and control their respective output locations for activation or deactivation of specific groups of neurons is desirable but remains unachieved. Here, we discuss our probe’s capability to deliver two independently controllable wavelengths (450 and 655 nm) in the location(s) of interest using nanophotonic directional couplers and ring resonators. These nanophotonics are scalable to dozens of outputs without significantly increasing the device’s lateral dimensions. Furthermore, they are entirely passive and thus do not require electrical input that results in heat generation. Besides, we integrate a high number of electrodes for a simultaneous neural activity readout. Thus, we overcome the challenges associated with multicolor illumination for neural devices by exploiting the capability of miniaturizable, passive probes to deliver two different frequencies in several areas of interest. These devices open the path towards investigating the in vivo electrical signal propagation under the individual or simultaneous activation or inhibition of distinct brain regions.

Due to its unique features, laser-induced graphene (LIG) can be considered as disruptive technology for creating a few-layer graphene-based film that received much attention in the field of flexible electronics. Among all, energy storage, catalysis, sensing, and separation are the main applications that have been investigated in recent years with large improvements in the respective device performance. In particular, miniaturized supercapacitor—usually called a micro-supercapacitor (μSC)—is the most investigated field in which LIG can strongly provide outstanding results concerning the state of the art simplification of the fabrication procedure and intrinsically allowing the flexibility of the device. However, many open points still limit the possible full exploitation of this technology in the energy storage sector. This paper provides a concise overview of the LIG application in μSCs suggesting where the community should direct efforts to enhance the results together with associated challenges.

Emerging technologies, such as portable electronics, have had a huge impact on societal norms, such as access to real time information. To perform these tasks, portable electronic devices need more and more accessories for the processing and dispensation of the data, resulting in higher demand for energy and power. To overcome this problem, a low cost high-performing flexible fiber shaped asymmetric supercapacitor was fabricated, exploiting 3D-spinel manganese oxide Mn3O4 as cathode and 2D molybdenum disulfide MoS2 as anode. These asymmetric supercapacitors with stretched operating voltage window of 1.8 V exhibit high specific capacitance and energy density, good rate capability and cyclic stability after 3000 cycles, with a capacitance retention of more than 80%. This device has also shown an excellent bending stability at different bending conditions.

This paper presents a critical review and the state of the art of graphene porous membranes, a brand-new technology and backdrop to discuss its potential application for efficient water desalination in low salinity water injection (LSWI). LSWI technology consists in injecting designed, adequately modified, filtered water to maximize oil production. To this end, desalination technologies already available can be further optimized, for example, via graphene membranes, to achieve greater efficiency in water-oil displacement. Theoretical and experimental applications of graphene porous membranes in water desalination have shown promising results over the last 5-6 years. Needless to say, improvements are still needed before graphene porous membranes become readily available. However, the present work simply sets out to demonstrate, at least in principle, the practical potential graphene membranes would have in hydrocarbon recovery processes.

The fabrication of innovative 2D materials-based composite electrodes is here presented. Graphene oxide (GO) and molybdenum disulfide (MoS2) were dispersed in water-based solution and after drop casting onto a titanium (Ti) mesh and fast GO reduction a flexible rGO/MoS2 electrode was obtained and exploited for supercapacitor application. The structural, physical and chemical properties of the samples were analyzed by electron microscopy, energy dispersive X-ray spectroscopy, contact angle measurements and infrared spectroscopy while electrochemical characterizations were conducted on the assembled device in two electrodes configuration. The promising electrochemical performance observed pave the way to the exploitation of the proposed approach for flexible and wearable supercapacitors fabrication.

This paper reports the exploitation of Cu2O nanoparticles and reduced graphene oxide (rGO) in a sonication treatment for the production of rGO- Cu2O imperfect micro-cubes nanocomposite. This strategy was implemented in order to fabricate a hybrid binder-free electrode for electrochemical energy storage into supercapacitors. Instead of hazardous chemical compounds, Ascorbic acid was simultaneously used as reducing agent and morphology controller of the nanocomposite as well. The structural properties of rGO-Cu2O imperfect micro-cubes nanocomposite were studied by X-Ray diffraction (XRD) analyses, field emission scanning electron and transmission electron microscopy (FE-SEM and TEM) imaging, energy dispersive X-ray (EDX) elemental mapping, X-ray photoelectron spectroscopy (XPS) and surface area analyses. Based on structural investigation, the rGO-Cu2O nanocomposite with the morphology of attached Cu2O imperfect micro-cubes to rGO nanosheets possessing a high surface area containing pores and channels in different sizes was used as electrode materials for the charge storage. Electrochemical measurements including cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), electrochemical impedance spectroscopy (EIS) and XPS analysis revealed that rGO-Cu2O imperfect micro-cubes nanocomposite modified electrode without binder has used three distinct processes of forming electrochemical double layer, redox reactions and ion diffusion for charge storage somehow it is introduced as a hybrid binder-free electrode. According to the GCD analysis, the stored charge value was calculated 960 C.g−1 at current density of 1 A.g−1, the cycling stability was examined in that the 87% of initial stored charge value was remained after 10,000 cycles.

In this work we investigated the behavior of TiO2 nanotube (NT) arrays, grown by anodic oxidation of Ti foil, as catalysts for the oxygen reduction reaction (ORR) in alkaline water solution. In particular, as-grown amorphous NTs were compared to crystalline anatase nanostructures, obtained following two different procedures, namely thermal and vapor-induced crystallizations. The catalytic activity of these materials toward the ORR was evaluated by cyclic voltammetry measurements. ORR polarization curves, combined with the rotating disk technique, indicated a predominant four-electrons reduction path, especially for crystalline samples. The effect of the structural characteristics of the investigated materials on the catalytic activity was analyzed in details by electrochemical impedance spectroscopy. The catalytic performance of the crystalline NTs is only slightly lower with respect to the reference material for fuel cell applications, namely platinum, but is in line with other cost-effective catalysts recently proposed in the literature. However, if compared to the larger part of these low-cost catalysts, anodically-grown TiO2 NTs are characterized by a synthesis route which is highly reproducible and easily up-scalable.

Due to their inherent safety, low cost, and structural stability, TiO2 nanostructures represent a suitable choice as anode materials in sodium-ion batteries. In the recent years, various hypotheses have been proposed regarding the actual mechanism of the reversible insertion of sodium ions in the TiO2 structure, and previous reports are often controversial in this respect. Interestingly, when tested as binder- and conducting additive-free electrodes in laboratory-scale sodium cells, amorphous and crystalline (anatase) TiO2 nanotubular arrays obtained by simple anodic oxidation exhibit peculiar and intrinsically different electrochemical responses. In particular, after the initial electrochemical activation, anatase TiO2 shows excellent rate capability and very stable long-term cycling performance with larger specific capacities, and thus a clearly superior response compared with the amorphous counterpart. To obtain deeper insight, the present materials are thoroughly characterized by scanning electron microscopy and ex situ X-ray diffraction, and the insertion of sodium ions in the TiO2 bulk phases is systematically modeled by density functional theory calculations. The present results may contribute to the development of more systematic screening approaches to identify suitable active materials for highly efficient sodium-based energy storage systems.

More and more attention has recently been paid to the electrochemical treatment of wastewater for the degradation of refractory organics, such as phenol and its derivatives. The electrodeposition of different types of manganese oxides (MnOx) over two substrates, namely metallic titanium and titania nanotubes (TiO2-NTs), is reported herein. X-Ray Diffraction (XRD) and X-Ray Photoelectron Spectroscopy (XPS) analyses have confirmed the formation of different oxidation states of the manganese, while Field Emission Scanning Electronic Microscopy (FESEM) analysis has helped to point out the evolutions in the morphology of the samples, which depends on the electrodeposition parameters and calcination conditions. Moreover, cross section FESEM images have demonstrated the penetration of manganese oxides inside the NTs for anodically deposited samples. The electrochemical properties of the electrodes have been investigated by means of cyclic voltammetry (CV) and linear sweep voltammetry (LSV), both of which have shown that both calcination and electrodeposition over TiO2-NTs lead to more stable electrodes that exhibited a marked increase in the current density. The activity of the proposed nanostructured samples toward phenol degradation has been investigated. The cathodically electrodeposited manganese oxides (α-MnO2) have been found to be the most active phase, with a phenol conversion of 26.8%. The anodically electrodeposited manganese oxides (α-Mn2O3), instead, have shown higher stability, with a final working potential of 2.9 V vs. RHE. The TiO2-NTs interlayer has contributed, in all cases, to a decrease of about 1–1.5 V in the final (reached) potential, after a reaction time of 5 h. Electrochemical impedance spectroscopy (EIS) and accelerated life time tests have confirmed the beneficial effect of TiO2-NTs, which contributes by improving both the charge transfer properties (kinetics of reaction) and the adhesion of MnOx films.

A facile and scalable approach is here proposed to fabricate fiber-shaped electrodes and their integration into wearable supercapacitors. Copper wires were used as axial current collector and covered by dip coating with a carbon-based slurry. A gel electrolyte was used both as ionic conductor and separator between the two parallel wire-electrodes. The decoration of the carbon-based active material with ZnO nanoparticles was investigated in order to boost the supercapacitors performance exploiting the pseudocapacitive response of this wide band-gap semiconductor. Composites of ZnO/graphite with different wt.% ZnO (such as 1, 5, 10, 20% of ZnO nanoparticles) were prepared. X-ray powder diffraction and Raman micro spectroscopy served as phase-analytical methods. Field emission scanning electron microscopy technique was used for morphology characterization of the prepared samples. The electrical characterization of the devices showed excellent results both in terms of specific capacitance and cycling and bending stability. The ease of the proposed process can allow its rapid integration in a large-scale production for efficient wearable supercapacitors.

In this paper we propose the exploitation of TiO 2 nanotube arrays as biocompatible electrodes for implantable supercapacitors. TiO 2 nanotubes are obtained by anodic oxidation of titanium foil and the assembly of the whole energy storage device is conducted using only biocompatible materials: PDMS is selected as packaging material both for its biocompatibility and easy fabrication process, glass-fiber filter acts as separator and the Dulbecco’s Phosphate Buffered Saline solution as physiological electrolyte. Electrochemical characterizations of the proposed flexible device reveal promising performances of TiO 2 nanotubes array for future implantable supercapacitors.

A modo de resumen, los estudios realizados para definir la relevancia de los rafts lipídicos en el proceso de adhesión de B. pertussis a células epiteliales están descritos en el Capítulo 2, estos estudios indican que B. pertussis se adhiere a dominios lipídicos en un proceso dependiente de FHA. En el Capítulo 3 se describen los estudios realizados para evaluar la capacidad de B. pertussis para invadir y sobrevivir en células epiteliales respiratorias y el rol de los rafts en este proceso. Los estudios indican que B. pertussis ingresa a las células epiteliales por un mecanismo dependiente de rafts lipídicos, microtúbulos y la activación de tirosin quinasas. Un porcentaje de bacterias es capaz de sobrevivir en localización intracelular lo que sugiere que la invasión de células epiteliales podría constituir un mecanismo de evasión de la respuesta inmune. En el Capítulo 4 se describen los estudios realizados para caracterizar la interacción de B. pertussis con neutrófilos humanos en presencia y en ausencia de anticuerpos opsonizantes y el rol de los rafts lipídicos en la evasión de la respuesta inmune. Los estudios indican que bajo condiciones no opsonizantes B. pertussis es capturada y fagocitada a través de dominios rafts lo que determina que la bacteria sea transportada a compartimientos no lisosomales donde evade la acción bactericida de estas células inmunes. Por el contrario, la fagocitosis mediada por anticuerpos conlleva a la inactivación de la bacteria en compartimientos lisosomales poniendo énfasis en la importancia de la presencia de anticuerpos opsonizantes en el sitio de infección. En el Capítulo 5 se describen estudios que evalúan el tráfico intracelular de B. pertussis luego de ser fagocitada por los macrófagos humanos así como los mecanismos de sobrevida a largo plazo. Los estudios indican que bajo condiciones no opsonizantes B. pertussis no sólo es capaz de sobrevivir por varios días dentro de los macrófagos sino que es capaz de replicar en compartimientos con características de endosomas tempranos. A su vez, estos estudios indican que la presencia de anticuerpos opsonizantes es fundamental para prevenir la replicación intracelular. En el Capítulo 6 se presenta la Discusión General de este trabajo. En un Anexo de esta Tesis se presentan los estudios realizados para evaluar el rol de la variación antigénica en Prn, único antígeno presente en las actuales formulaciones vacunales que induce la producción de anticuerpos opsonizantes, en la evasión de las cepas circulantes a la respuesta inmune inducida por vacunación.

Bordetella parapertussis is one of the pathogens that cause whooping cough. Even though its incidence has been rising in the last decades, this species remained poorly investigated. This study reports the first extensive proteome analysis of this bacterium. In an attempt to gain some insight into the infective phenotype, we evaluated the response of B. parapertussis to iron starvation, a critical stress the bacteria face during infection. Among other relevant findings, we observed that the adaptation to this condition involves significant changes in the abundance of two important virulence factors of this pathogen, namely, adenylate cyclase and the O-antigen. We further used the proteomic data to search for B. parapertussis proteins that are absent or classified as pseudogenes in the genome of Bordetella pertussis to unravel differences between both whooping cough causative agents. Among them, we identified proteins involved in stress resistance and virulence determinants that might help to explain the differences in the pathogenesis of these species and the lack of cross-protection of current acellular vaccines. Altogether, these results contribute to a better understanding of B. parapertussis biology and pathogenesis. Significance: Whooping cough is a reemerging disease caused by both Bordetella pertussis and Bordetella parapertussis. Current vaccines fail to induce protection against B parapertussis and the incidence of this species has been rising over the years. The proteomic analysis of this study provided relevant insights into potential virulence determinants of this poorly-studied pathogen. It further identified proteins produced by B. parapertussis not present in B. pertussis, which might help to explain both the differences on their respective infectious process and the current vaccine failure. Altogether, the results of this study contribute to the better understanding of B. parapertussis pathogenesis and the eventual design of improved preventive strategies against whooping cough. Fil: Oviedo, Juan Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina Fil: Surmann, Kristin. University Medicine Greifswald; Alemania Fil: Gorgojo, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina Fil: Valdez, Hugo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina Fil: Dhople, Vishnu M.. University Medicine Greifswald; Alemania Fil: Lamberti, Yanina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina Fil: Völker, Uwe. University Medicine Greifswald; Alemania Fil: Rodriguez, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina

Mesoporous zinc oxide (ZnO) scaffolds coated with drop-cast graphene oxide (GO) flakes are proposed to be a novel bilayer system featuring bioactivity, biocompatibility, and promising loading/release properties for controlled drug-delivery systems. The high-surface-area ZnO scaffolds show clear apatite deposition, but their particular surface chemistry and topography prevent the formation of a continuous coating, resulting in micrometric crystalline apatite aggregates after 28 days in simulated body fluid (SBF). When gentamicin sulfate (GS) is considered as a model molecule, pure ZnO scaffolds also show functional GS loading efficiency, with fast in vitro release kinetics driven by a simple diffusion mechanism. Strikingly, the bioactivity and GS delivery properties of mesoporous ZnO are efficiently triggered by drop-casting GO flakes atop the mesoporous scaffold surface. The resulting ZnO@GO bilayer scaffolds show the formation of a uniform apatite coating after 28 days in SBF and demonstrate a biocompatible behavior, supporting the culture of SaOS-2 osteoblast-like cells. Moreover, the GO coating also leads to a barrier-layer effect, preventing fast GS release, particularly in the short time range. This barrier effect, coupled with the existence of nanopores within the GO structure, sieves drug molecules from the mesoporous ZnO matrix and allows for a delayed release of the GS molecule. We, thus, demonstrated a new-generation ZnO@GO bilayer system as effective multifunctional and biocompatible scaffold for bone tissue engineering.

2018 will be the brightest year for upstream investment since 2014. Costs reduction and the oil price stabilization gives operators confidence in launching new challenging projects. However, launching new projects is still particularly challenging for deep-water assets. Even if project costs are 20% lower than mid-2014, deep-water projects are not yet competitive with tight oil, considering also the higher associated uncertainty. The direction to improve is clear: further cost cuts, through leaner development principles and improved well designs. Moreover, operators have to take advantage from lesson learned of projects already in production. Eni has consolidated on its West Africa deep-water assets a workflow that can support challenging projects FID through: Reduction of time to market parallelizing project phasesManagement of project uncertainty through flexibilityWork in integrated teams taking advantage from digital transformation More in details, the first target is to reduce time to market anticipating free cash flow generation. This is achieved through an appraisal while developing phase: drilling appraisal as first wells of development campaign, derisking the following well locations. Time-to-market reduction is achieved by parallelizing development phases, starting development plan definition during exploration phases and anticipating procurement of long lead items. This is possible if subsurface uncertainty has been properly defined through robust 3D models and if projects can guarantee the flexibility to capture new opportunities: fine tune well locations during drilling campaign, keep spare slots availability and sidetrack opportunities, substitute water and gas injectors with water alternate gas wells (WAG). In addition, Digital Transformation offers more and more the possibility to continuously update 3D models thanks to the availability of real time data, run thousands of simulations on super computers and monitor in real time field performance, taking advantage from simple daily operations. This work is aimed to describe the steps that were the key successful factors of Eni operated deep water projects in West Africa. The presented workflow can now be considered a standard approach for the most challenging Eni's projects and supported the company to reach record time-to-market for the execution of challenging deep-water projects in the range of 2,5 to 4 years from authorization to first oil.

Wearable wire-shaped supercapacitors were fabricated exploiting an innovative graphene aerogel self-assembly procedure on copper wire. The innovative aspect of the proposed procedure lies in the employment, for the first time to the best of our knowledge, of a hydrothermal graphene synthesis for an in situ coverage of a non-planar substrate. Specific capacitance per unit length was calculated to be about 12,5 mF/cm. The device can sustain repeated charge–discharge and bending cycles without suffering significant deterioration of specific capacitance. The combination of graphene aerogel self-coating method, flexibility and superior electrochemical performance makes the proposed device a suitable power source for e-textile applications.

Many research efforts point nowadays towards the development of flexible, lightweight and efficient energy storage devices. Herein we report a simple procedure for the fabrication of nanostructured electrodes based on CuxO nanowire/nanoporous layer grown on copper foils and we propose, for the first time to the best of our knowledge, their integration into solid-state pseudo-supercapacitors. An easy and scalable thermal oxidation process in ambient atmosphere is employed to grow a CuxO film on Cu substrates. Electron microscopy, contact angle measurements, infrared and X-Ray photoelectron spectroscopy are employed to obtain a deep understanding of the morphology, wettability, structure and composition of the copper oxides. We show that the annealing time strongly influences the nanostructures formation promoting the evolution of the oxide film from Cu2O to CuO/Cu2O bilayer with the subsequent growth of CuO nanowires. The obtained materials represent flexible and binder-free electrodes for pseudo-supercapacitors in which the current collector and the active element are joined in the same substrate without further processing. The electrical characterizations of symmetric devices fabricated with a polymeric electrolyte show the pseudo-capacitive behavior of the proposed nanostructures.

Summary We present and test a new screening methodology to discriminate among alternative and competing enhanced-oil-recovery (EOR) techniques to be considered for a given reservoir. Our work is motivated by the observation that, even if a considerable variety of EOR techniques was successfully applied to extend oilfield production and lifetime, an EOR project requires extensive laboratory and pilot tests before fieldwide implementation and preliminary assessment of EOR potential in a reservoir is critical in the decision-making process. Because similar EOR techniques may be successful in fields sharing some global features, as basic discrimination criteria, we consider fluid (density and viscosity) and reservoir-formation (porosity, permeability, depth, and temperature) properties. Our approach is observation-driven and grounded on an exhaustive database that we compiled after considering worldwide EOR field experiences. A preliminary reduction of the dimensionality of the parameter space over which EOR projects are classified is accomplished through principal-component analysis (PCA). A screening of target analogs is then obtained by classification of documented EOR projects through a Bayesian-clustering algorithm. Considering the cluster that includes the EOR field under evaluation, an intercluster refinement is then accomplished by ordering cluster components on the basis of a weighted Euclidean distance from the target field in the (multidimensional) parameter space. Distinctive features of our methodology are that (a) all screening analyses are performed on the database projected onto the space of principal components (PCs) and (b) the fraction of variance associated with each PC is taken as weight of the Euclidean distance that we determine. As a test bed, we apply our approach on three fields operated by Eni. These include light-, medium-, and heavy-oil reservoirs, where gas, chemical, and thermal EOR projects were, respectively, proposed. Our results are (a) conducive to the compilation of a broad and extensively usable database of EOR settings and (b) consistent with the field observations related to the three tested and already planned/implemented EOR methodologies, thus demonstrating the effectiveness of our approach.

In this work flexible composite nanogenerators were prepared aiming to identify and optimize the exploitation of the piezoelectric effect in mechanical energy harvesting. A novel shape-controlled synthesis of ZnO microstructures through hydrothermal route was achieved resulting in different morphologies and aspect-ratio particles, microwires, multipods, and desert-roses. The three different microparticles and round-shaped commercial nanoparticles were incorporated into a polydimethylsiloxane matrix and a comparative study on the piezoelectric output power dependence on the filler morphology was carried out. The highest performances, i.e. output voltage of 10 V and a maximum power of 55 µW, were obtained with the highest aspect-ratio ZnO filler, the microwires, dispersed in the PDMS matrix at a 40 wt% concentration. Considering the generated voltage dependence on the size and aspect-ratio of the fillers, a working mechanism was formulated. The nanogenerators were then exploited to charge a homemade carbon-based supercapacitor. The voltage charging curves confirm the voltage generation trend based on the high aspect-ratio particles, showing that the best performances are obtained by the microwires-based composite nanogenerator. This work thus contributes to clarify the piezoelectric mechanism in composite nanogenerators and to maximize the output power generation in view of self-powered nanodevices able to recover and store waste environmental energy.

Herein we report the fabrication and electrochemical characterization of a novel type of supercapacitor composed of laser-induced graphene (LIG) electrodes, achieved by the laser-writing of polyimide foils, and 1-Butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide ionic liquid as electrolyte. This combination allows the development of a flexible microsupercapacitor suitable for harsh environment application. The influence of several parameters is evaluated with the aim of maximizing the performance of the flexible pouch-bag devices, such as the laser-writing conditions, type of electrode layout and amount of nitrogen-doping. Among them, the laser writing conditions are found to strongly influence the areal capacitance allowing to achieve about 4 mF cm−2, as measured from the galvanostatic charge-discharge measurement at 10 µA cm−2, with a maximum operating potential range of 3 V at 25 °C. In order to probe the potential application of such device, i) flexible pouch architecture and ii) high temperature measurements (considering harsh environment field) are investigated. This type of flexible device exhibits energy and power density as high as 4.5 µWh cm−2 and 90.5 µW cm−2, respectively, high cycling stability as well as acceptable coulombic efficiency above 97% demonstrating good stability even at high bending condition (1.25 cm of bending radius). The electrochemical measurements increasing temperature up to 100 °C reveal a 300% of rise in capacitance and 43% of increment in energy density at de-rated voltage. The obtained energy storage performance are comparable to the best data ever reported for a microsupercapacitor for high temperature application. Moreover, a de-rated voltage analysis (DVA) is proposed as a safe procedure to characterize an energy storage device in an extended temperature range without compromising the system performances.

The electric response of a capacitive deionisation cell submitted to a periodic external electric field is investigated. The case in which the applied potential has a nonzero average value on one period (polarised cell) is considered. The theoretical analysis of the experimental data, relevant to nearly symmetric electrodes, is done in the framework of the Poisson-Nernst-Planck model. The current densities on the electrodes are described by kinetic equations related to the adsorption phenomenon in the presence of a bias potential. We propose a new form for the Langmuir isotherm in which the effective adsorption coefficients depend on the bias potential according to the Boltzmann statistics. This kinetic equation extends the Butler-Volmer equation for non-blocking electrodes also to the blocking ones. The equation proposed here is such that for dc external voltage the total current across the electrodes vanishes.

Emerging technologies, such as portable electronics, have had a huge impact on societal norms, such as access to real time information. To perform these tasks, portable electronic devices need more and more accessories for the processing and dispensation of the data, resulting in higher demand for energy and power. To overcome this problem, a low cost high-performing flexible fiber shaped asymmetric supercapacitor was fabricated, exploiting 3D-spinel manganese oxide Mn3O4 as cathode and 2D molybdenum disulfide MoS2 as anode. These asymmetric supercapacitors with stretched operating voltage window of 1.8 V exhibit high specific capacitance and energy density, good rate capability and cyclic stability after 3000 cycles, with a capacitance retention of more than 80%. This device has also shown an excellent bending stability at different bending conditions.

B. pertussis is the etiological agent of whooping cough, a highly contagious respiratory disease which remains uncontrolled worldwide. Understanding how this pathogen responds to the environmental changes and adapts to different niches found inside the host might contribute to gain insight into bacterial pathogenesis. Comparative analyses of previous transcriptomic and proteomic data suggested that post-transcriptional regulatory mechanisms modulate B. pertussis virulence in response to iron availability. Iron scarcity represents one of the major stresses faced by bacterial pathogens inside the host. In this study, we used gel-free nanoLC-MS/MS-based proteomics to investigate whether Hfq, a highly conserved post-transcriptional regulatory protein, is involved in B. pertussis adaptation to low iron environment. To this end, we compared the protein profiles of wild type B. pertussis and its isogenic hfq deletion mutant strain under iron-replete and iron-depleted conditions. Almost of 33% of the proteins identified under iron starvation was found to be Hfq-dependent. Among them, proteins involved in oxidative stress tolerance and virulence factors that play a key role in the early steps of host colonization and bacterial persistence inside the host cells. Altogether these results suggest that Hfq shapes the infective phenotype of B. pertussis. Significance: In the last years, it became evident that post-transcriptional regulation of gene expression in ba cteria plays a central role in host-pathogen interactions. Hfq is a bacterial protein that regulates gene expression at post-transcriptional level found pivotal in the establishment of successful infections. In this study, we investigated the role of Hfq in Bordetella pertussis response to iron starvation, one of the main stresses imposed by the host. The data demonstrate that Hfq regulates the abundance of a significant number of B. pertussis proteins in response to iron starvation. Among them, virulence factors and proteins involved in oxidative stress tolerance, key players in host colonization and intracellular bacterial survival. Altogether, our results suggest a relevant role of Hfq in B. pertussis adaptation to the different niches found inside the host eventually granting bacterial pathogenesis. Fil: Alvarez Hayes, Jimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina Fil: Surmann, Kristin. University Medicine Greifswald; Alemania Fil: Lamberti, Yanina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina Fil: Depke, Maren. University Medicine Greifswald; Alemania Fil: Dhople, Vishnu. University Medicine Greifswald; Alemania Fil: Blancá, Bruno Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina Fil: Ruiz, María Esperanza. Universidad Nacional de La Plata. Facultad de Ciencas Exactas. Laboratorio de Investigación y Desarrollo de Bioactivos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Vecerek, Branislav. Institute of Microbiology of the ASCR; República Checa Fil: Schmidt, Frank. University Medicine Greifswald; Alemania Fil: Völker, Uwe. University Medicine Greifswald; Alemania Fil: Rodriguez, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina

A dye-sensitized solar module (DSSM) and a high voltage all-solid-state electrochemical double layer capacitor (EDLC) are, for the first time, implemented in a compact Harvesting-Storage (HS) device. Conductive glass is employed as current collecting substrate for both DSSM and EDLC, leading to a robust and portable final structure. The photovoltaic section is constituted by a 4 series cells W-type module, while in the storage section an EDLC employing an ionic liquid-based polymeric electrolyte (a mixture of polyethylene oxide and N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide, PEO-Pyr14TFSI) and activated carbon electrodes is used. The solid state EDLC is first characterized individually to determine its electrochemical performance before successfully proving the integration with the DSSM. The harvesting-storage properties of the integrated photo-capacitor are evaluated through photo-charge and subsequent discharge protocols performed at two different discharge currents, showing that in this configuration the EDLC unit can be effectively charged up to 2.45 V.

This work describes a case of a light oil field in Sub-Saharan Africa. Soon after the start up, the production wells showed a productivity index different from expectation. In particular, well test analysis showed different stabilizations between build-up and drawdown. Since the well is flowing with pressure below the bubble point, the impact of oil permeability reduction due to presence of free gas around the wellbore was considered as a possible explanation and was investigated. We applied well test analysis on synthetic data generated by numerical simulation. The analysis confirms the different stabilizations between pressure build-up and drawdown, as observed from the real field case, when the flowing bottomhole pressure is below the bubble point pressure. The different flow capacity is caused by gas saturation around the wellbore, which reduces the effective permeability to oil, hence the productivity index. Besides this, we experienced that a full field model with large grid size is not able to represent this phenomenon. Due to the grid size, the full field model shows less pressure drop than the radial sector model, hence different gas saturation calculation. We showed that in order to simulate the effect without impacting on simulation time, applying higher well skin instead of local grid refinement can be a way forward.

In the challenging scenario of anode materials for sodium-ion batteries, TiO2 nanotubes could represent a winning choice in terms of cost, scalability of the preparation procedure, and long-term stability upon reversible operation in electrochemical cells. In this work, a detailed physicochemical, computational, and electrochemical characterization is carried out on TiO2 nanotubes synthesized by varying growth time and heat treatment, viz. the two most significant experimental parameters during preparation. A chemometric approach is proposed to obtain a concrete and solid multivariate analysis of sodium battery electrode materials. Such a statistical approach, combined with prolonged galvanostatic cycling and density functional theory analysis, allows identifying anatase at high growth time as the TiO2 polymorph of choice as an anode material, thus creating a benchmark for sodium-ion batteries, which currently took the center stage of the research in the field of energy storage systems from renewables.