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Metastases in the liver frequently grow as scattered tumor nodules which neither can be removed by surgical resection nor focally ablated. Previously, we have proposed a novel technique based on irreversible electroporation which may be able to simultaneously treat all nodules in the liver while sparing healthy tissue. The proposed technique requires increasing the electrical conductivity of healthy liver by injecting a hypersaline solution through the portal vein. Aiming to assess the capability of increasing the global conductivity of the liver by means of hypersaline fluids, here it is presented a mathematical model which estimates the NaCl distribution within the liver and the resulting conductivity change. The model fuses wellestablished compartmental pharmacokinetic models of the organ with saline injection models employed for resuscitation treatments and it considers changes in sinusoidal blood viscosity due to the hypertonicity of the solution. Here it is also described a pilot experimental study in pigs in which different volumes of NaCl 20% (from 100 to 200 ml) were injected through the portal vein at different flow rates (from 53 to 171 ml/min). The in vivo conductivity results fit those obtained by the model, both quantitatively and qualitatively, being able to predict the maximum conductivity with a 14.6% average relative error. The maximum conductivity value was 0.44 S/m which corresponds to increasing four times the mean basal conductivity (0.11 S/m). The results suggest that the presented model is well suited for predicting on liver conductivity changes during hypertonic saline injection. ; Spanish Government; contract/grant number: TEC2014-52383-C3-1-R, TEC2014-52383-C3-2-R and TEC2014-52383-C3-3-R

The problem associated with mixtures of fillers and polymers is that they result in mechanical degradation of the material (polymer) as the filler content increases. This problem will increase the weight of the material and manufacturing cost. For this reason, experimentation on the electrical conductivities of the polymer-composites (PCs) is not enough to research their electrical properties ; models have to be adopted to solve the encountered challenges. Hitherto, several models by previous researchers have been developed and proposed, with each utilizing different design parameters. It is imperative to carry out analysis on these models so that the suitable one is identified. This paper indeed carried out a comprehensive parametric analysis on the existing electrical conductivity models for polymer composites. The analysis involves identification of the parameters that best predict the electrical conductivity of polymer composites for energy storage, viz: (batteries and capacitor), sensors, electronic device components, fuel cell electrodes, automotive, medical instrumentation, cathode scanners, solar cell, and military surveillance gadgets applications. The analysis showed that the existing models lack sufficient parametric ability to determine accurately the electrical conductivity of polymer-composites.

The problem associated with mixtures of fillers and polymers is that they result in mechanical degradation of the material (polymer) as the filler content increases. This problem will increase the weight of the material and manufacturing cost. For this reason, experimentation on the electrical conductivities of the polymer-composites (PCs) is not enough to research their electrical properties; models have to be adopted to solve the encountered challenges. Hitherto, several models by previous researchers have been developed and proposed, with each utilizing different design parameters. It is imperative to carry out analysis on these models so that the suitable one is identified. This paper indeed carried out a comprehensive parametric analysis on the existing electrical conductivity models for polymer composites. The analysis involves identification of the parameters that best predict the electrical conductivity of polymer composites for energy storage, viz: (batteries and capacitor), sensors, electronic device components, fuel cell electrodes, automotive, medical instrumentation, cathode scanners, solar cell, and military surveillance gadgets applications. The analysis showed that the existing models lack sufficient parametric ability to determine accurately the electrical conductivity of polymer-composites.

This is the peer reviewed version of the following article: Ares, P., Amo‐Ochoa, P., Soler, J. M., Palacios, J. J., Gómez‐Herrero, J., & Zamora, F. (2018). High electrical conductivity of single metal–organic chains. Advanced Materials, 30(21): 1705645, which has been published in final form at https://doi.org/10.1002/adma.201705645. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions ; Molecular wires are essential components for future nanoscale electronics. However, the preparation of individual long conductive molecules is still a challenge. MMX metal–organic polymers are quasi-1D sequences of single halide atoms (X) bridging subunits with two metal ions (MM) connected by organic ligands. They are excellent electrical conductors as bulk macroscopic crystals and as nanoribbons. However, according to theoretical calculations, the electrical conductance found in the experiments should be even higher. Here, a novel and simple drop-casting procedure to isolate bundles of few to single MMX chains is demonstrated. Furthermore, an exponential dependence of the electrical resistance of one or two MMX chains as a function of their length that does not agree with predictions based on their theoretical band structure is reported. This dependence is attributed to strong Anderson localization originated by structural defects. Theoretical modeling confirms that the current is limited by structural defects, mainly vacancies of iodine atoms, through which the current is constrained to flow. Nevertheless, measurable electrical transport along distances beyond 250 nm surpasses that of all other molecular wires reported so far. This work places in perspective the role of defects in 1D wires and their importance for molecular electronics ; This work was supported by MINECO projects Consolider CSD2010‐00024, MAT2016‐77608‐C3‐1‐P and 3‐P, FIS2012‐37549‐C05‐03, FIS2015‐64886‐C5‐5‐P, and FIS2016‐80434‐P. J.S., J.J.P., J.G.H., and F.Z. acknowledge financial support through The "María de Maeztu" Programme for Units of Excellence in R&D (MDM‐2014‐0377). The authors thank A. Gil for insightful discussions. J.J.P. also acknowledges the European Union structural funds and the Comunidad de Madrid under Grant Nos. S2013/MIT‐3007 and S2013/MIT‐2850; the Generalitat Valenciana under Grant No. PROMETEO/2012/011, and the computer resources and assistance provided by the Centro de Computación Científica of the Universidad Autónoma de Madrid and the RES

Introduction of bio-composites into aircraft interior and airframe secondary structures is subjected to major technical challenges such as the enhancement of mechanical, thermal, electrical and electromagnetic shielding properties of bio-sourced materials. In this paper, electrical conductivity and electromagnetic shielding effectiveness of two bio-composites have been studied by tests and numerical models. Two monolithic composites with partly bio-based content were manufactured. The first bio-composite is made of a carbon fibre fabric prepreg and a partly bio-based (rosin) epoxy resin (CF/Rosin). The second bio-composite is a combination of prepregs of carbon fibre fabric / epoxy resin and flax fibre fabric / epoxy resin (CF-Flax/Epoxy). A single line infusion process has been used prior to the curing step in the autoclave. Both variants are exemplary for the possibility of introducing bio-based materials in high performance CFRP. In-plane and out-of-plane electrical conductivity tests have been conducted according to Airbus standards AITM2 0064 and AITM2 0065, respectively. Electromagnetic shielding effectiveness tests have been conducted based on the standard ASTM D 4935-10. Materials were prepared at the German Aerospace Center (DLR) while characterization tests were conducted at the University of Patras. In addition to the tests, numerical models of representative volume elements have been developed using the DIGIMAT software to predict the electrical conductivity of the two bio-composites. The preliminary numerical results show a good agreement with the experimental results. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 690638 and the Special Research Plan on Civil Aircraft of Ministry for Industry and Information of the People's Republic of China (MIIT) under Grant No MJ-2015-H-G-103.

The salinity tolerance of plants can be improved by efficient irrigation management and salt flushing, which require a continuous and precise knowledge of the salinity in the soil or substrate. Soil sensors that measure electrical conductivity play an essential role in monitoring soil salinity. However, the correct interpretation of salinity measurements using soil sensors depends on developing appropriate salinity indexes. This work studied the potential of several salinity indexes based on the bulk EC (ECb) directly measured by soil sensors, and on pore water EC (ECw) estimated by the Hilhorst model (ECwHI). The methodology used in the experiments is based on the simultaneous use of scales and sensors, which allowed the automatic monitoring of the real salinity levels of the substrate, and the conductivity measurements made with the soil sensor. Regression studies were carried out to know how well the proposed salinity indexes explain real salinity. In general, all the indexes were suitable for estimating the relative changes in substrate salinity, as long as they met certain requirements. For example, ECwHI was seen to be a reliable salinity index when substrate moisture was high and constant. However, there was no such requirement when the ECwHI was corrected according to the current substrate water content, or when the salinity index was calculated as the average of the ECwHI values between two successive irrigation events. ECb was an efficient salinity indicator as long as the moisture content was constant, although its accuracy increased at a high moisture level. The findings led us to propose a new salinity index calculated with the slopes of the linear section of the quadratic moisture adjustment, which avoids the need for the substrate moisture content to be constant. ; This research was funded by the Ministry of Science, Innovation, and Universities of Spain, and the European Regional Development Fund, grant number RTI2018-093997-B-I00, and by the Spanish AEI (grant number PCI 2019-103608) under the PRIMA programme in the frame of the PRECIMED project. PRIMA is an Art.185 initiative supported and co-funded under Horizon 2020, the European Union's Programme for Research and Innovation