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Proposes guidelines for matching the mechanical properties of stamps to the requirements of their use for soft lithography. Master and stamp fabrication; Conformal contact; Sinusoidal roughness; Sphere-cap model; Local deformation of patterns; Replication accuracy of features.

Abstract GERMINAL is a fuel performance code developed by the French Commission of Alternative and Atomic Energies (CEA) to simulate the in-pile behaviour of mixed oxide fuel pins for Sodium-cooled Fast Reactors. The code is continuously being improved. GERMINAL was initially designed to simulate the fuel pin behaviour of the PHENIX and SUPER-PHENIX reactors, which were built in France and have been in operation over the last decades. The GERMINAL models were then extended and improved to meet the needs of the design studies of ASTRID, a project of a technological Sodium Fast Reactor demonstrator in France. The goal of this article is to introduce the current modelling implemented in GERMINAL. The code is validated and the validation work is illustrated here by a selection of comparisons between calculations and measurements. Working perspectives for further modelling improvements are finally presented, through more mechanistic approaches sustained by three-dimensional computations or based on extended physical couplings. Highlights • The GERMINAL fuel performance code of the PLEIADES simulation platform is introduced. • GERMINAL is dedicated to the simulation of sodium-cooled fast reactor fuel behaviour. • The modelling implemented in GERMINAL is described. • The code validation is illustrated using comparisons between calculations and measures. • Working perspectives for further modelling improvements and developments are presented. [ABSTRACT FROM AUTHOR]

Highlights • Vertical channels enhance mass transfer and sorption rate in SAPO-34 coatings. • Optimal structuring is predicted by a characteristic transport length model. • Power-energy product per cycle is enhanced by 100% through structuring. • Structured coatings outperform other SAPO-34 configurations at short cycle times. Abstract The rate of water adsorption in SAPO-34 zeolite coatings for adsorption heat pumps has been shown to be limited by mass transfer. In the present contribution, uniformly spaced longitudinal channels of width 75 µm were introduced into SAPO-34 coatings and their effect on the heat and mass transport limitations during water sorption was explored. Different channel spacings at constant adsorbent mass per unit area were tested by means of temperature-swing adsorption measurements and thermal impedance analysis (TIA). The optimal ratio between the characteristic transport length (CTL) for heat transfer and the CTL for mass transfer was 6, which is in agreement with the TIA predictions and was validated experimentally. Geometries with CTL ratios greater or less than 6 exhibited higher thermal impedance and lower rates of water sorption. At the optimal CTL ratio, the water sorption rate was enhanced 2x at the same adsorbent mass per unit area when compared to unstructured SAPO-34 coatings. Compared to other adsorbent structures reported in literature, the structured coatings exhibit the highest power density and energy density at short cycle times. These findings may be used to improve efficiency and/or power in temperature-swing processes in which mass transfer in adsorbent coatings is rate-limiting. It is recommended to develop methods to structure coatings at the scales relevant for commercial adsorption heat pump modules, and further investigate the rate-limiting transport mechanisms in large adsorption heat exchanger modules. [ABSTRACT FROM AUTHOR]

Highlights • Rate of water sorption in SAPO-34 coatings is limited by mass transport. • Higher vapor pressure accelerates adsorption and slightly decelerates desorption. • Ragone plots provide the pareto-optimal cycle time for power and efficiency. • Mass transport must be improved to increase power & efficiency in coated adsorbers. Abstract Adsorption heat pumps have become an increasingly viable technology to use waste heat or renewable thermal energy for heating and cooling. The power density of this emerging technology is limited by the rate of heat and/or mass transfer in the adsorption heat exchanger (AdHEX) which drives investment costs. This work presents an experimental analysis of the mass and heat transfer during water sorption on SAPO-34 coatings to determine the limiting transport mechanism in state-of-the-art AdHEX. Isochoric temperature swings were carried out and evaluated using a recently introduced method to determine the relative importance of heat and mass transport impedances. Coatings with thicknesses between 60 and 460 µm were investigated and in all cases the sorption dynamics were limited by mass transport. Ragone plots were used to characterize the power and energy trade-off during thermal cycling of SAPO-34 in water vapor to identify the pareto-optimal cycle time for a specific coating thickness. With the knowledge of the rate-limiting mechanism, the overall transport rates of adsorbent coatings can systematically be improved to enhance transport rates in next-generation AdHEX. [ABSTRACT FROM AUTHOR]

L'axe intestin-cerveau ou microbiote-intestin-cerveau fait l'objet de recherches intensives depuis plus d'une décennie. Les études précliniques se multiplient pour tenter de mieux comprendre en quoi la composition de notre microbiote et ses éventuelles modifications peuvent guider nos comportements voire contribuer à des troubles neuropsychiatriques. Les voies de communication entre l'intestin et le cerveau sont de mieux en mieux cernées, et l'importance à la fois du nerf vague et des neurométabolites produits par la flore microbienne est aujourd'hui établie. Les probiotiques apparaissent comme des stratégies médicamenteuses intéressantes et leur bénéfice potentiel pour les maladies psychiques a permis de légitimer la terminologie de psychobiotiques désormais employée dans la littérature scientifique. Cependant, leur pertinence réelle en clinique reste encore à démontrer, notamment dans les troubles anxiodépressifs, compte tenu du peu d'études structurées disponibles à ce jour. À côté des probiotiques, la transplantation fécale apparaît comme une alternative importante pour restaurer la composition du microbiote. Ces stratégies potentielles apparaissent comme des recours d'avenir face à l'accumulation des preuves sur les dérèglements du microbiote observés par exemple dans la dépression, la schizophrénie ou encore l'autisme. [ABSTRACT FROM AUTHOR]

The 22nd ISPOR (International society for pharmacoeconomics and outcomes research) Conference was held in Boston, May 20-24, 2017. A group of pharmacists, physicians and health economists attended the conference and reported some of the highlights. During the congress, there was a widespread and enthusiastic debate on the exploitation of big data, their usefulness for health policy decisions and coming challenges. In this paper, the authors discussed the following questions from the different sessions and/or posters: Real-life databases: What are they? What reliability and methodologies? What operating potentials? What uses are applied to medical devices? Will they be able to supplement the randomized clinical trials? [ABSTRACT FROM AUTHOR]

Le méthotrexate est le médicament de première intention dans le traitement de fond de la polyarthrite rhumatoïde et des rhumatismes psoriasiques de mauvais pronostic. Bien qu'habituellement correctement toléré à faibles doses, le méthotrexate, de par son mécanisme d'action, peut entraîner une toxicité hématologique, et la question de sa réintroduction après un épisode de cytopénie est délicate. Plusieurs facteurs favorisants ont été décrits, tels que l'hypoalbuminémie, l'insuffisance rénale, l'âge supérieur à 70 ans, une carence en folates ou une comédication délétère. L'apparition d'une ou plusieurs cytopénies sous méthotrexate nécessite la suspension du médicament. La question de la reprise du traitement se fera suivant l'origine de l'effet indésirable (l'hypersensibilité au méthotrexate contre-indique la reprise), la sévérité (une agranulocytose ou une pancytopénie profonde constituent également une contre-indication) et l'évolution de la cytopénie. Notre propos est illustré par le cas de deux patients. [ABSTRACT FROM AUTHOR]

The coffee berry borer, Hypothenemus hampei (Ferrari), is a major insect pest of coffee crops worldwide. As part of a program of studies aimed at efficient and sustainable pest control, a study was conducted to determine the mating status of adult females in the broader context of studying pest dispersal behavior. To that end, it was deemed important to determine the morphology of the H. hampei female reproductive tract. This study focused on direct observation of the spermatheca of unmated, and colonizing adult females obtained from natural field populations with a high probability of having mated, and the description of all organs of the reproductive tract using established standard staining and microscopy techniques. Spermathecae were extracted from the samples and sorted according to their origin (unmated or colonizing females). The morphology of sperm present in the female spermathecae was compared with that of sperm taken directly from male testes. Two staining techniques using Giemsa and chlorazol black allowed spermatheca and sperm to be distinguished from other tissues. Under these conditions, a more precise description of the spermatheca was achieved, including the spermathecal duct and spermathecal muscles, spermathecal gland, and, for the first time, sperm when present. These techniques permitted the accurate and rapid determination of the presence or absence of sperm in the spermathecae of H. hampei females, thereby establishing their mating status. [ABSTRACT FROM AUTHOR]

In this study, we reconstruct the first time-calibrated phylogeny of the iconic antlion family, the Myrmeleontidae (Neuroptera: Myrmeleontiformia). We use maximum likelihood and Bayesian inference to analyse a molecular dataset based on seven mitochondrial and nuclear gene markers. The dataset encompasses 106 species of Neuroptera, including 94 antlion species. The resulting phylogenetic framework provides support for a myrmeleontid classification distinguishing four subfamilies: Acanthaclisinae, Myrmeleontinae, Palparinae, and Stilbopteryginae. Within Myrmeleontinae, Myrmecaelurini and Nemoleontini are recovered as monophyletic clades; Gepini also appears as a valid tribe, distinct from Myrmecaelurini whereas Myrmecaelurini and Nesoleontini on one hand and Brachynemurini and Dendroleontini on the other hand, appear closely related. Some preliminary information related to generic and specific levels are also implied from our results, such as the paraphyly of several genera. Dating analyses based on thoroughly evaluated fossil calibrations indicate that the antlion family likely originated in the Cretaceous, between 135 and 138 million years ago (depending on the set of fossil calibrations), and that all higher-level lineages appeared during the Early Cretaceous. This first phylogenetic hypothesis will provide a valuable basis to further expand the taxonomic coverage and molecular sampling, and to lay the foundations of future systematic revisions. [ABSTRACT FROM AUTHOR]

Background: Healthcare cost savings are closely linked to prescribers' confidence in and acceptance of the prescription of biosimilar drugs. Objectives: The aim of this study was to assess the knowledge, experience and opinions of hospital-based and office-based French rheumatologists with regard to biosimilar medicines and to identify the barriers to and possible options to promote their prescription. Methods: A web-based, self-administered survey was conducted among French rheumatologists from June 8 to August 2, 2015. Results: A total of 116 rheumatologists responded to the survey. Many reported having little knowledge and a lack of available information about biosimilar drugs, especially office-based rheumatologists. 98.3% of the respondents had at least one question about biosimilars, and seven in ten raised issues regarding substitution, iatrogenic effects or cost savings that might be achievable. Only eight rheumatologists had already prescribed a biosimilar drug. The most common barriers reported were indication extrapolation and a lack of data about tolerability. Nine out of ten physicians thought that starting a treatment with a biosimilar drug in biologic treatment-naïve patients was possible. The rheumatologists' opinions were rather favorable towards the implementation of biosimilars, but a majority expressed a negative opinion about substitution by the pharmacist. Conclusions: Our survey gave a better appreciation of the concerns associated with biosimilar prescriptions. Targeted communication initiatives, deeper experience and availability of new clinical data may help to address the outstanding questions and should overcome the misunderstandings surrounding biosimilar drugs among rheumatologists. [ABSTRACT FROM AUTHOR]

Objectives: To identify both type and frequency of the challenges community pharmacists face when dispensing drugs from hospital discharge prescriptions, to describe the measures undertaken to resolve the issues at stake and to list their consequences.Design: We carried out an observational study in the community pharmacies of the French region of Alsace and asked the community pharmacy staff to review 537 hospital discharge prescriptions in 2013 using anonymous data collection forms.Setting and Participants: Nineteen community pharmacies.Main Outcome Measures: Number of patients informed about their medication (at hospital and/or community pharmacy), type and frequency of issues encountered during drug dispensing, type and frequency of measures undertaken to resolve the issues, type and frequency of the consequences regarding drug dispensing.Results: Community pharmacists faced 165 challenges from 145 hospital discharge prescriptions (i.e. 27.5% out of 528 analysed prescriptions), mostly correlated to the quality of the prescriptions (n = 100, 60.6%) or to logistical matters (n = 54, 32.7%). A mere 36.8% of the patients received information pertaining to their medication while being hospitalized. Of note, 40.5% of the prescriptions were delivered to pharmacies within 2 days following the patients' discharge. In order to resolve the different issues preventing drugs from being dispensed (n = 33/145 prescriptions), pharmacists sought information, mainly from patients, colleagues and hospital prescribers. The pharmacists were able to dispense all the drugs prescribed in 138 out of 145 cases (95.2%).Conclusions: This study highlighted the challenges encountered by community pharmacists and their significant contribution to the continuity of care upon patients being discharged from hospitals. [ABSTRACT FROM AUTHOR]

Touchant de nombreux domaines thérapeutiques tels que la rhumatologie, la gastroentérologie ou encore la cancérologie, les médicaments biosimilaires sont au coeur de l'actualité et font l'objet de nombreux débats. Mais que sont véritablement les médicaments biosimilaires, et quels sont les enjeux liés à leur prescription et à leur délivrance ? Loin d'être de simples copies, les médicaments biosimilaires sont des molécules complexes et hétérogènes du fait de leur procédé de fabrication, produites à l'aide des mêmes technologies que les biomédicaments de référence. Leur autorisation de mise sur le marché est conditionnée par des exigences réglementaires strictes, requérant la démonstration de leur équivalence en comparaison au biomédicament de référence en termes de qualité, d'efficacité et de sécurité. L'intérêt de prescrire un médicament biosimilaire est avant tout économique. Les économies de santé réalisables et la libération des ressources pour traiter davantage de patients sont les principaux bénéfices liés aux médicaments biosimilaires aujourd'hui reconnus par la plupart des professionnels de santé. De nombreuses difficultés sont toutefois rapportées : défaut de connaissances et d'information sur le sujet, manque d'essais cliniques à long terme et de données sur l'interchangeabilité, insuffisance de données sur l'immunogénicité, craintes liées à l'extrapolation de l'efficacité établie dans une seule indication thérapeutique, à toutes les indications du médicament de référence, etc. De plus, ces molécules sont parfois confondues avec des médicaments biologiques non originaux, lesquels sont des copies de biomédicaments non évaluées dans des conditions réglementaires rigoureuses. Le recul apporté par de nouvelles études et par le suivi de pharmacovigilance, ainsi que l'expérience croissante d'utilisation des médicaments biosimilaires, devraient permettre aux professionnels de santé de dépasser un certain nombre de ces barrières. [ABSTRACT FROM AUTHOR]

The PLEIADES software environment is devoted to the thermomechanical simulation of nuclear fuel elements behaviour under irradiation. This platform is co-developed in the framework of a research cooperative program between Électricité de France ( EDF ), AREVA and the French Atomic Energy Commission ( CEA ). As many thermomechanical solvers are used within the platform, one of the PLEAIADES’s main challenge is to propose a unified software environment for capitalisation of material knowledge coming from research and development programs on various nuclear systems. This paper introduces a tool called mfront which is basically a code generator based on C++ (Stroustrup and Eberhardt, 2004). Domain specific languages are provided which were designed to simplify the implementations of new material properties, mechanical behaviours and simple material models. mfront was recently released under the GPL open-source licence and is available on its web site: http://tfel.sourceforge.net/ . The authors hope that it will prove useful for researchers and engineers, in particular in the field of solid mechanics. mfront interfaces generate code specific to each solver and language considered. In this paper, after a general overview of mfront functionalities, a particular focus is made on mechanical behaviours which are by essence more complex and may have significant impact on the numerical performances of mechanical simulations. mfront users can describe all kinds of mechanical phenomena, such as viscoplasticity, plasticity and damage, for various types of mechanical behaviour (small strain or finite strain behaviour, cohesive zone models). Performance benchmarks, performed using the Code_Aster finite element solver, show that the code generated using mfront is in most cases on par or better than the behaviour implementations written in fortran natively available in this solver. The material knowledge management strategy that was set up within the PLEIADES platform is briefly discussed. A material database named sirius proposes a rigorous material verification workflow. We illustrate the use of mfront through two case of studies: a simple FFC single crystal viscoplastic behaviour and the implementation of a recent behaviour for the fuel material which describes various phenomena: fuel cracking, plasticity and viscoplasticity. [ABSTRACT FROM AUTHOR]

A model reproducing strain softening behavior in ceramic materials is proposed. This model is base on a critical treatment of previous mechanical experimental results, mainly on uranium dioxide. The main hypothesis is that the strain softening phenomenon is related to an aging process, where some point defects move towards the dislocations and modify their velocity. This is different from most of models used up to now, as they were based on the hypothesis that only the initial lack of dislocations was responsible of the strain softening behavior. A model is first developed in a simple 1D framework. Evolution of the mechanical behavior with strain rate and temperature is well reproduced by this model. Then, the 1D model is extended to a 3D mechanical model, and mechanical compressive tests on UO 2 pellets are simulated. The 3D model well reproduces the observed asymmetrical shape of the compressed pellet if one considers that the material is not initially perfectly homogeneous, which highlights the importance of accounting for spatial heterogeneity of materials in models. [ABSTRACT FROM AUTHOR]

The seasonality of insect assemblages in Africa is poorly investigated. To provide information on the relationships between climate and insect assemblages in the Sudanian region, strongly affected by climate change, we studied Myrmeleontidae and Ascalaphidae assemblages (Insecta: Neuroptera) for 7 and 5 consecutive years respectively in southern Mali. To make the species inventory as exhaustive as possible, we performed weekly sampling by netting and light trapping. For both assemblages, results showed very similar patterns of variation in species diversity throughout the year. Adults of Myrmeleontidae and Ascalaphidae were active all year, and the species succession was influenced by a strong temporal segregation. Species diversity peaked at the end of the rainy season and surprisingly during the dry season. Principal component analysis of the climatic factors followed by co-inertia analysis applied to two data sets, one comprising climatic factors and the other reporting presence/absence of species, showed a good association between the annual trend of climatic factors and the species diversity. But no well defined species grouping was clearly linked to a particular period of the year. This tight association between climate and species composition suggests that even small climate changes could modify significantly species assemblage characteristics. [ABSTRACT FROM AUTHOR]

Abstract: In this Letter, we investigate the nanoscale heat transfer across hydrophilic silanol and hydrophobic silane interfaces. We calculate the thermal conductance at the interface via the vibrational relaxation of silica in aqueous solutions. Additionally, we directly determine the heat flux across the interface by non-equilibrium molecular dynamics. The results indicate a temperature and time dependence of the thermal conductance across the hydrophilic interface, whereas the conductance at the hydrophobic one stays constant, emphasizing the importance of hydrogen-bonded networks. Most importantly, we observe a rectifying effect of the hydrophilic silanol to the bulk substrate depending on the heat current direction. [Copyright &y& Elsevier]

Focuses on the development of a lithography providing high resolution based on flexography printing. Ability of printing to distribute ideas; Details on the printing processes indicating contact transfer of patterns; Characteristic of soft lithography.

Presents a miniaturized mosaic immunoassays based on patterning lines of antigens onto a surface by means of a microfluidic network. Channels of a second muFN across the patterns; Specific binding of the target antibodies; Solutions in a combinatorial fashion with great economy of reagents.

The resistivities of thin metal films and wires are highly sensitive to their polycrystalline structure and surface morphology because grain boundaries and surfaces provide additional scattering sites compared to bulk materials. Here, we investigated polycrystalline gold wires of nanometer-scale diameter that were—at some locations—connected through single grain boundaries. A detailed topography of the wires was recorded by atomic force microscopy. A Pt-coated tip in a conducting atomic force microscopy setup served as a mobile electrode to probe the resistance of a wire. Analyzing the topographical cross section and the resistance data allowed us to evaluate the effective specific resistivity of the wire as well as reflection coefficients of single grain boundaries. [ABSTRACT FROM AUTHOR]

Purpose Recommendations to improve therapeutics are proposals made by pharmacists during the prescription review process to address suboptimal use of medicines. Recommendations are generated daily as text documents but are rarely reused beyond their primary use to alert prescribers and caregivers. If recommendation data were easier to summarize, they could be used retrospectively to improve safeguards for better prescribing. The objective of this work was to train a deep learning algorithm for automated recommendation classification to valorize the large amount of recommendation data. Methods The study was conducted in a French university hospital, at which recommendation data were collected throughout 2017. Data from the first 6 months of 2017 were labeled by 2 pharmacists who assigned recommendations to 1 of the 29 possible classes of the French Society of Clinical Pharmacy classification. A deep neural network classifier was trained to predict the class of recommendations. Results In total, 27,699 labeled recommendations from the first half of 2017 were used to train and evaluate a classifier. The prediction accuracy calculated on a validation dataset was 78.0%. We also predicted classes for unlabeled recommendations collected during the second half of 2017. Of the 4,460 predictions reviewed, 67 required correction. When these additional labeled data were concatenated with the original dataset and the neural network was retrained, accuracy reached 81.0%. Conclusion To facilitate analysis of recommendations, we have implemented an automated classification system using deep learning that achieves respectable performance. This tool can help to retrospectively highlight the clinical significance of daily medication reviews performed by hospital clinical pharmacists. [ABSTRACT FROM AUTHOR]

The article presents the case study of a 58-year-old chronic schizophrenic patient who has been suffering from various side effects of a combination of antipsychotics including clozapine. These side effects include constipation, orthostatic hypotension, and nausea. The patient developed reflux esophagitis associated with hiatal hernia due to clozapine.

Palparine and palparidiine antlions constitute an emblematic clade of large and occasionally colourful insects that are only distributed in the western portion of the Eastern hemisphere, with about half of the known species diversity occurring exclusively in Southern Africa. Little is known about their evolutionary history, and the boundaries and relationships of most genera are still unresolved. In this study, we analyse a molecular dataset consisting of seven loci (five mitochondrial and two nuclear genes) for 144 antlion species and provide the first phylogenetic hypothesis for a representative sampling of Palparini and Palparidiini (62 Palparini species, representing 15 of the 17 known genera, and all three known Palparidiini species). In addition, we reconstruct their timing of diversification and historical biogeography. The resulting tree indicates that several extant palparine genera are polyphyletic or paraphyletic and provides interesting leads that ought to be helpful for future taxonomic revisions; it also enables us to re‐evaluate the taxonomic utility and relevancy of a number of morphological characters that were previously used to define some genera. Molecular dating analyses indicate that the most recent common ancestor of both groups originated about 92 million years ago (Ma) in the Late Cretaceous. Finally, the results of historical biogeography analyses provide strong support for an origin in Southern Africa, which further acted as both a cradle of diversification and a springboard for successive waves of northern dispersals. [ABSTRACT FROM AUTHOR]

The article presents information on two case reports of thrombocytopenia with quetiapine, one with positive rechallenge. It says that antipsychotic thrombocytopenia is generally rare, but seems to happen more frequently with quetiapine. It adds that the relative risk of thrombocytopenia can be explained as very rare with loxapine and clozapine.

Developing strategies to reduce mass and heat transport limitations is one of the most important challenges in adsorption heat exchanger technology. Due to the strong coupling of mass and heat transport in these systems, it is difficult to determine the individual transport limitations quantitatively. In order to find an optimal design where heat and mass transport are balanced, a quantitative method that enables a direct comparison of these two transport phenomena is needed. In the present work, a novel experimental approach to discriminate between mass and heat transport is proposed based on the measurement of adsorbent temperature, heat exchanger surface temperature and vapor pressure. The methodology is applied to micro/mesoporous silica spheres arranged in a monolayer or bilayer loose grain configuration or in a monolayer configuration adhesively bonded to the substrate. While the monolayer configuration exhibits balanced heat and mass transport, we find that the bilayer and the thermally enhanced configurations are limited by heat and mass transport, respectively. The application of the proposed methodology to compare heat and mass transport limitations in other industrially-relevant adsorbent materials should greatly aid the design of more efficient adsorption heat exchangers for a wide range of applications. [ABSTRACT FROM AUTHOR]

The mechanical behaviour of UO 2 single crystal is under debate due to the unexpected multi-slip observations in the experiments that involve dislocations in 1 2 〈 110 〉 { 100 } slip systems but also in 1 2 〈 110 〉 { 110 } and 1 2 〈 110 〉 { 111 }. We propose a multi-scale model based on a composite slip in which, under the effect of cross-slip, part of the dislocation density in primary slip systems can be transferred in secondary systems with a lower propensity to glide but a more favourable orientation regarding the shear stress. This approach allows to describe the anisotropic mechanical response of UO 2 single crystal with an accuracy never reached up to now. After identifying the relevant slip systems depending on the orientation using a Schmid approach, dislocation dynamics simulations are used to assert if the cross-slip induces a composite slip and to quantify its effect on the flow stress which appears constrained by the activity of 1 2 < 110 > { 111 } systems. In agreement with this result, the composite slip is adapted to couple the activity of slip systems with common Burger vectors in a crystal plasticity framework for a closer comparison to the experiment. This multi-scale approach significantly improves our current knowledge on the links between dislocation microstructures and mechanical properties in UO 2. Composite slip mechanism appears as a candidate to explain unexpected plastic behaviours as often observed in complex materials with multiple slip modes underling that slip activation may be more complex than in usual constitutive laws. [Display omitted] [ABSTRACT FROM AUTHOR]

This work is devoted to the modeling of the mechanical behavior of coated or uncoated silicon nanoparticles, which constitute the anode active material in some lithium ion batteries, during their first lithiation at room temperature. The lithiation process induces a large volume expansion of the particles and a high level of stresses, which can lead to the fragmentation of the particles. Several approaches are proposed in order to estimate the volume expansion and the stress levels experienced by the particles. An original semi-analytical small strain model is first presented, which adapts the solution proposed by Seck et al. (2018) of the elastic-viscoplastic composite sphere problem subjected to radial loading, to the lithiated particle problem, in particular by considering the variation of phases properties during lithiation. The lithium concentration in the silicon particle is given by a sigmoid function (called logistic function) in order to mimic the reaction front between the phases. The implementation of the approach using the Hencky strain tensor Miehe et al. (2002) is proposed to take into account the large strains experienced by the particles. A complete description of the formulation is provided and the advantages are discussed. The importance of the large strains model is established by comparing it with the small strain one concerning the predictions of the pushing-out effect and the size effect of particles on their internal stresses during lithiation. Comparisons between our simulations and experimental data from Tardif et al. (2017) measuring the operando strain experienced by the pristine silicon gives the yield stress of the lithiated silicon. In addition, carbon-coated silicon nanoparticles are finally studied. We develop original closed-form expressions to predict the maximal stresses experienced by the coating at the end of the lithiation. Those expressions are used to re-estimate the fracture stress of pyrolitic carbon, considering a critical review of both pyrolitic carbon and lithiated silicon elastic properties. Finally, the mechanical effect of the coating on silicon during lithiation is studied. • The stress and strain evolutions in coated/uncoated silicon nanoparticles during their first lithiation are analyzed. • A large strain finite element model using an accurate logarithmic strain framework is proposed. • This large strain finite element model predicts well the strain measurements obtained by XRD. • Estimates of key material properties (plastic and fracture thresholds) are derived by comparison with experiments. • New closed-form expressions of the stresses experienced by the particles during lithiation are assessed. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the Licos fuel performance code which has been developed for several years within the platform pleiades , co-developed by the French Alternative Energies and Atomic Energy Commission (CEA) and its industrial partners Électricité de France (EDF) and AREVA. CEA engineers have been using Licos to back multidimensional thermo-mechanical studies on innovative fuel elements design and experimental device pre-and post-irradiation computations. Studies made with Licos thus encompass a wide range of situations, including most nuclear systems used or studied in France in recent years (PWR, SFR or GFR), normal and off-normal operating conditions, and a large selection of materials (either for fuel, absorber, coolant and cladding). The aim of this paper is to give some insights about some innovative features in the design of Licos (dependency management, kriging, mfront , etc.). We also present two studies that demonstrate the flexibility of this code. The first one shows how Licos can be combined with the Germinal monodimensional fuel performance code to demonstrate the interest of a three dimensional modelling of the fuel relocation phenomenon in the Sodium Fast Reactor fuel pin. The second one describes how Licos was used to model the DIAMINO experiment. [ABSTRACT FROM AUTHOR]

A list of 91 species of thrips from Guadeloupe and Martinique, including 28 new records, is provided. New data on the ecology of some species and additional records of parasitoids and predators of thrips are given. A list of plants is provided on which populations of thrips have been observed, in some cases, with the presence of immature stages and/or thrips feeding damage. [ABSTRACT FROM AUTHOR]

Background: Non–small cell lung cancer (NSCLC) is a leading cause of cancer deaths. Its treatment includes specific oral tyrosine kinases inhibitors (TKIs). Objectives: To estimate adherence and persistence among patients receiving TKIs and to assess the economic burden of the unused medicines in Alsace (France). Method: This retrospective study was carried out using the Insurance Healthcare database. Main outcome measures: Adherence was calculated using medication possession ratio (MPR), persistence using estimated level of persistence with therapy (ELPT) and economic impact using prescription refill data. Results: 242 patients were receiving TKIs. The most common TKIs prescribed were erlotinib (75.6%, n = 183) and crizotinib (12.8%, n = 31). Total of 149 patients were included in the adherence analysis. Overall MPR was 0.98. 180 patients were included in the persistence analysis. Almost half of patients had stopped treatment at 60 days and only 38.3% (n = 69) were still persistent with the therapy at 120 days. The expenses related to unused TKIs amounted to €356,392 and were related majorly to treatment discontinuation followed by overlapping refills, patient deaths and dose- or drug-switching, respectively. Conclusions: Our data indicated overall adherence medicines above the acceptable limit of 0.80 but also pointed out a significant decline in persistence over time. The resulting economic losses justify the need for physicians and pharmacists to closely monitor their patients to ensure continuity of treatment. To limit the cost associated with unused medicines, interventions such as app-based monitoring, dispensing TKIs per unit over shorter periods and not only on monthly intervals could be implemented. [ABSTRACT FROM AUTHOR]

The aim of this paper is to introduce the PLEIADES framework offering a set of services and numerical tools to model and simulate the behavior of nuclear fuels of different concepts of reactors. The framework provides in particular the following features: interfaces to manipulate meshes and fields, services to deal with different physical solvers, setup of coupling trees to realize multiphysics partitioned (accelerated) fixed point couplings, automated time-marching algorithm, checkpoint/restart strategies, capability to realize on-the-fly multiscale couplings. It is built with a permanent concern for sustainability, scalability and maintainability. PLEIADES framework supports multidimensional simulations, typically 1D, 2D and 3D, possibly multilayered. To date, this framework relies on the generic thermomechanical finite elements solver Cast3M to deal with partial derivative problems (mechanical, thermal or diffusion problems) at the scale of the structure or the (heterogeneous) microstructure. It also makes use of so-called point models (mainly based on ODE — ordinary differential equations) to describe the local (mesoscale) evolution of the material through the physics of irradiation. Several software applications are built on the PLEIADES framework, they can use its parallel features to use multiple processors. The multilayered calculation scheme provides a way to loosen the computations and access to a good parallel performance up to hundred cores. It is also possible to achieve efficient scalable concurrent multiscale simulations through finite element square (FE 2) computational homogenization algorithms. • Introduction of the PLEIADES framework, dedicated to nuclear fuel behavior simulation. • Structuring and computational choices of the PLEIADES framework are described. • The multiphysics coupling is solved through an accelerated block fixed-point strategy. • Multiscale global/local coupling and computational homogenization are also available. • Parallel PLEIADES features based on MPI communications are detailed. [ABSTRACT FROM AUTHOR]

Abstract: A detailed thermo-hydrodynamic analysis of a hot water cooled manifold microchannel heat sink for electronic chip cooling is presented. The hot water cooling enables efficient recovery of heat dissipated by the even hotter chip by using hot water recovered from a secondary application. Contrary to usual expectation of laminar flow in electronic cooling, high flow rate and high fluid temperatures result in turbulent flow conditions in the inlet and outlet manifolds of the heat sink with predominantly laminar flow conditions in microchannels. To simulate these complex flow conditions, a three dimensional (3D) conjugate heat transfer model with turbulent flow is developed. Microchannel heat transfer structure is modeled as porous medium with permeability parameters extracted from a 3D model for a single microchannel. The energetic performance of the heat sink is analyzed in terms of 2nd law efficiency and sources of exergy destruction are identified by detailed local entropy generation analysis at low and high Reynolds number conditions of 2400 and 11200 respectively. This analysis shows that entropy generation due to heat transfer dominates the net entropy generation in the heat sink for both conditions. Although entropy generation due to viscous dissipation increases significantly with increased Reynolds number, it still contributes less than a third to the total entropy generated at high Reynolds numbers. Use of hot water reduces the heat transfer component of entropy generation significantly, thus leading to higher 2nd law efficiency. [Copyright &y& Elsevier]

Abstract: This article is the second part of a study on flow boiling of R236fa and R245fa. This part presents the heat transfer coefficients obtained in a 12.7mm silicon evaporator composed of 135 microchannels with 85μm wide and 560μm high channels separated by 46μm wide fins. There were 35 local heaters and temperature measurements arranged in a 5×7 array. The heat transfer results were uniform in the lateral direction to the flow (attributable to the inlet restriction) and a function of the heat flux, vapor quality and mass flux. The steady-state standard deviation of the local base temperature was less than 0.2°C, inferring that the boiling process was very stable. For wall heat fluxes over 45kW/m2, the heat transfer coefficient curves were V-shaped, decreasing for intermittent flow regimes and increasing for annular flow. The three-zone model of was the best heat transfer prediction method when setting the dryout thickness equal to the channel roughness. [Copyright &y& Elsevier]

Abstract: Three micro-evaporator cooling cycles, one with a pump, one with a compressor and a hybrid of the two together, are proposed for cooling a computer blade server. The hybrid cycle is characterized by the interchangeability between the first two cycles, where the decision on the cycle to operate is based on the season (necessity or economical benefit for heat recovery) or the maintenance of cycle’s driver. The main characteristics of each cycle are presented as well as the details of the micro-evaporator cooler for the blade’s CPU. Analysis of the cycle overall efficiency and the potential for heat recovery shows that the best cycle to use depends mainly on the end application of the heat recovered. Four refrigerants were evaluated as the possible working fluids for cooling the microprocessors. HFC134a and HFC245fa were found to be the best choices for the desired application. [Copyright &y& Elsevier]

• A new finite element implementation to solve porosity advection and heat transfer. • Numerical stabilization techniques to avoid spurious oscillations in the porosity solution. • Verification tests and improvement assessment compared to BISON. • New 2D simulation results to assess the crack induced porosity contribution. • Comparison of the crack induced porosity contribution against an experimental data. We present an engineering-scale model for the migration of porosity in a fuel pellet experiencing a temperature gradient. The system of coupled pore advection and heat diffusion equations governing the problem is solved by a fixed-point iteration technique. The coupling between porosity and temperature fields is considered via the dependency of pore advection velocity on the local temperature and temperature gradient, and via the dependency of fuel thermal conductivity and of the volumetric power source on the local porosity. We employ the finite element method to discretize the resulting equations. As pure advection solutions obtained by this method are well-known to present spurious spatial oscillations, we introduce stabilization techniques in the pore advection equation. The proposed model is first tested against a benchmark problem representative for the conditions of an uranium-plutonium oxide fuel pellet irradiated in a sodium fast reactor. The results are compared to the those obtained by a model implemented in the BISON fuel performance code. The analysis shows how the results of the newly developed model are in line with those obtained by the reference model, and underlines a superior stability of the solution. The model is then applied to analyze the contribution of as-fabricated and crack-induced porosities in determining the fuel restructuring and in particular the central hole formation. A comparison to experimental data shows the impact of considering crack-induced porosity to predict the extent of the central void. [ABSTRACT FROM AUTHOR]

We show a proof-of-concept in which we combine our previously published concepts of micromosaic immunoassays (μMIAs) with self-regulating microfluidic networks (μFNs) to detect C-reactive protein (CRP) and other cardiac markers such as myoglobin (Mb) and cardiac Troponin I (cTnI). The μFNs are microfabricated in Si, have a well-defined surface chemistry, and are affixed to a bibulous material so as to self-regulate the displacement of an aliquot of liquid through the μFNs using capillary forces. An open section of the channels of the μFNs is covered with a hydrophobic poly(dimethylsiloxane) (PDMS) slab that acts as the substrate for a solid-phase immunoassay. Here, individual assays are conducted using independent channels. These assays are “sequential”: series of samples, reagents, and buffers are displaced one after the other over the PDMS surface, and, as these assays are conducted under “microfluidic” conditions, they are fast to perform, very economical in their use of reagents, extremely integrated, and yield high-quality signals. The combinatorial character of μMIAs is exploited to optimize the assay parameters for detecting CRP. In particular, we found it optimal to deposit the capture antibody for CRP on PDMS at a concentration between 20 and 500 μg ml−1 in PBS in 1 min and to detect captured CRP in 2 min using a detection antibody having a concentration in PBS of 120 μg ml−1. With this method, CRP is quantitatively detected within 10 min in one microliter of human plasma down to concentrations of 30 ng ml−1, which suggests the possibility to detect CRP at clinically relevant concentrations for the management of coronary heart disease (CHD) and systemic inflammation. [Copyright &y& Elsevier]

The article offers information on the wishes for the new year 2024 from the editorial committee of the journal Cahiers Santé/Médecine Thérapeutique (Cs/Mt) to its readers, emphasizing health, happiness, and success. Topics include the importance of reader participation in contributing original articles, literature reviews, case studies, and other relevant contributions to the journal.

Using nonequilibrium molecular dynamics simulations, we study the thermal diode effect in a system composed of silica, self-assembled monolayers (SAMs) at the silica surface and water surrounding this system, by imposing a series of positive and negative heat currents. We have found that in the limit of large heat currents, the thermal conductance at the SAMs-water interface is about 1000 MW/m2 K at room temperature for heat flowing from the SAMs to the water and 650 MW/m2 K for heat flowing from the water to the SAMs, respectively, resulting in a thermal rectification of up to 54%. Analysis of the radial distribution function of oxygen-oxygen atoms in water indicates that the origin of the thermal rectification resides in the strong temperature dependence of the hydrogen bonds in water. [ABSTRACT FROM AUTHOR]

Understanding the mechanical behavior of uranium dioxide (UO 2) at high-temperature is of great interest to predict the behavior of the nuclear fuel under incidental operating conditions. Here, strengthening elementary processes and dislocation hardening coefficients are studied by the mean of Dislocation Dynamics (DD) simulations in UO 2. The three slip modes of the fluorite structure i.e., ½<110>{100}, ½<110>{110} and ½<110>{111} are modelled and all the possible dislocation configurations are analyzed and discussed. Averaged hardening coefficients are derived and their sensitivity to the sample orientation is discussed in the light of the seminal experimental work of Sawbridge and Sykes. This DD study gives rise to new insights about UO 2 mechanical behavior at high-temperature. • UO 2 dislocation strengthening is investigated by Dislocation Dynamics simulations. • Dislocation reaction maps and interaction matrix are computed for three gliding modes. • The role of several parameters is discussed with a results original post processing. • Hardening magnitudes depend on the individual or the multi-mode slip activation. • The strengthening sensitivity to the sample orientation is discussed. [ABSTRACT FROM AUTHOR]

Résumé: Le congrès européen 2018 de l'ISPOR Europe (International society for pharmacoeconomics and outcomes research) s'est tenu à Barcelone du 10 au 14 novembre 2018. Lors de ce congrès, ont été débattus les sujets d'actualités qui agitent le monde de la santé et bien au-delà : la santé numérique. Un groupe de pharmaciens, médecins et économistes en santé présents à Barcelone, a choisi de vous en restituer les messages forts. Dans cet article, les auteurs évoquent les questions issues des différentes sessions et/ou posters : après la libre circulation des personnes, des biens et services, l'Europe et le reste du monde sont confrontés à un nouveau mouvement : la « libre circulation des données », ce changement est-il une opportunité ou une menace pour la vie privée des patients ? La santé numérique peut-elle être source d'inégalités sociales ? Les métiers de la santé sont-ils menacés par l'intelligence artificielle (IA) notamment les économistes en santé ? Quelle sécurité dans l'utilisation des applications mobiles (Apps) et objets connectés (OC) ? Autant de questions discutées dans cet article pour l'enthousiasme ou le scepticisme qu'elles suscitent. The 2018 european congress of the ISPOR Europe (International society for pharmacoeconomics and outcomes research) was held in Barcelona from 10 to 14 November 2018. During the congress, the news topics that are stirring the world of health and far beyond were discussed: digital health. A group of pharmacists, physicians and health economists attended the conference and reported some of the highlights. In this paper, the authors discussed the following questions from the different sessions and/or posters. After the free movement of people, goods and services, Europe and the rest of the world should deal with a new trends: the "free flow of data". Is this change an opportunity or a threat to the privacy of patients? Can digital health be a source of social inequality? Are health professions threatened by artificial intelligence (AI) especially health economists? What security in the use of mobile applications (Apps) and connected objects (OC)? These are issues of both enthusiasm and concern that will be discussed according to the following plan. [ABSTRACT FROM AUTHOR]

Résumé: Le congrès de l'ISPOR Europe (International society for pharmacoeconomics and outcomes research) s'est tenu à Barcelone du 10 au 14 novembre 2018. Un groupe de pharmaciens, médecins et économistes en santé présents à Barcelone, a choisi de vous en restituer les messages forts. Les auteurs ont ainsi compilé les restitutions des différentes sessions en quatre grandes parties : 1) Quels sont les rôles des politiques de santé sur la pénétration des biosimilaires en Europe ? 2) L'aide informelle, trop souvent omise des études médico-économiques ; 3) Le programme de recherche médico-économique (PRME) français ; 4) Les économistes en santé face au public profane. The 2018 congress of the ISPOR Europe (International society for pharmacoeconomics and outcomes research) was held in Barcelona from 10 to 14 November 2018. A group of pharmacists, physicians and health economists attended the conference and reported some of the highlights. They have gathered some of the different outcomes and chosen to present them in four different paragraphs: What are the roles of health policies on the penetration of biosimilars in Europe? Informal care, too often omitted from medico-economic studies, The French programme for medico-economic research (PRME) and health economists in the face of lay audience. [ABSTRACT FROM AUTHOR]

Background: Although compelling evidence exists supporting statins (HMG-CoA reductase inhibitors) for secondary prevention in older patients with clinical atherosclerotic diseases, the same cannot be said for primary prevention. Objectives: The objectives of this study were to estimate the frequency of potential statin overuse in older patients, the potential drug cost savings if corrected, and the associated factors. Methods: A retrospective cross-sectional study was conducted in Alsace and Lorraine (France) from 1 January to 30 April 2017. All statin users aged 80 years or over living in the community (including nursing homes) and identified from the French health insurance database were analyzed. Potential statin overuse was defined according to the STOPP/START (Screening Tool of Older People's Prescriptions/Screening Tool to Alert to Right Treatment) criteria. Results: Among the 38,268 aged insured, 23,228 (60.7%) had potential statin overuse. Of those living in the community, 22,132 (60.0%) patients had potential statin overuse: 12,352 (55.8%) for primary and 9780 (44.2%) for secondary prevention. Among nursing home residents, 1096 (79.0%) had potential statin overuse: 394 (35.9%) for primary and 702 (64.1%) for secondary prevention. The potential drug cost savings associated with the adjustment of potential statin overuse were €924,100 for the study period. Living in nursing home [adjusted odds ratio (ORadjusted) 3.91, 95% confidence interval (CI) 2.82–5.41] and being a female (ORadjusted 2.84, 95% CI 2.54–3.17) were the main risk factors associated with potential statin overuse. Conclusion: The frequency of potential statin overuse is very high among older people aged 80 years or over, highlighting the need to re-evaluate statin therapy and consider deprescribing, particularly for primary prevention and in nursing homes. [ABSTRACT FROM AUTHOR]

Abstract The viscoplastic behavior of uranium dioxide (UO 2) single crystal is of great interest to perform predictive multiscale modeling of the nuclear fuel. Here, a viscoplastic model is built considering dislocation glide in ½<110>{100} and ½<110>{110} slip systems. The constitutive law parameters are determined adjusting the temperature dependency of the experimental critical resolved shear stress for both principal slip modes. Crystal plasticity finite element simulations of single crystal compression tests show a reasonable agreement with experimental viscoplastic anisotropy of UO 2. However, for specific orientations where ½<110>{111} slip is observed experimentally, significant differences remain between experimental and computed compression stresses. Therefore, the role of ½<110>{111} slip is investigated based on a parametric study that provides new insights on UO 2 plastic deformation. Several parameterizations of ½<110>{111} slip are tested highlighting the complexity of UO 2 viscoplastic behavior. Significant improvements are still required to explain all simulation-experiment gaps. Highlights • A viscoplastic model for UO 2 is proposed including material parameters derived from single crystal compression tests. • The model is used to investigate viscoplastic anisotropy and crystal lattice rotations. • A parametric analysis is performed to better understand the slip system activity of UO 2 at the grain scale. [ABSTRACT FROM AUTHOR]

Antiplatelet agents have proven to be beneficial in cardiovascular diseases. Their use concerns 5.6% of the French population. In secondary prevention, recommendations based on clinical trials frame the prescription of antiplatelet agents in the general population. In primary prevention, their use is controversial as counterbalanced by an increased haemorrhagic risk especially at the cerebral and digestive levels. Due to the heterogeneity of the geriatric population and in the absence of targeted studies, the strict application of the indications accepted for the general population is complex. In this article, recommendations of antiplatelet agents have been reviewing according to the main clinical situations in the general population and suggestions have been proposed regarding patients over 75 years old. [ABSTRACT FROM AUTHOR]

Integrated Flow-Cell Arrays (FCAs) represent a combination of integrated liquid cooling and on-chip power generation, converting chemical energy of the flowing electrolyte solutions to electrical energy. The FCA technology provides a promising way to address both heat removal and power delivery issues in 3D Multiprocessor Systems-on-Chips (MPSoCs). In this paper we motivate the benefits of FCA in 3D MPSoCs via a qualitative analysis and explore the capabilities of the proposed technology using our extended PowerCool simulator. PowerCool is a tool that performs combined compact thermal and electrochemical simulation of 3D MPSoCs with inter-tier FCA-based cooling and power generation. We validate our electrochemical model against experimental data obtained using a micro-scale FCA, and extend PowerCool with a compact thermal model (3D-ICE) and subthreshold leakage estimation. We show the sensitivity of the FCA cooling and power generation on the design-time (FCA geometry) and run-time (fluid inlet temperature, flow rate) parameters. Our results show that we can optimize the FCA to keep maximum chip temperature below 95 $^\circ$ C for an average chip power consumption of 50 W/cm2 while generating up to 3.6 W per cm2 of chip area. [ABSTRACT FROM AUTHOR]

Plasticity of irradiated UO 2 is of major interest to improve the risk assessment of the nuclear fuel cladding failure in the case of design basis accidents. In this study, we investigate the main irradiation-hardening processes induced by {110} irradiation loops interacting with glissile dislocations of the primary slip system, 1/2 < 110 > {001}, of UO 2. The interactions are simulated at two scales using molecular dynamics and discrete dislocation dynamics, to characterise local interactions and identify strengthening configurations as a function of the dislocation-irradiation loop geometry. In particular, we show that 1/2 < 110 > {001} screw dislocations can be strongly pinned by helical turn configurations. Statistical large-scale discrete dislocation simulations are performed to investigate the collective behaviour of a large density of irradiation defects and quantify irradiation hardening. Several microstructural processes including loop drag and shovelling are observed and their involvement in clear band formation and hardening of UO 2 fuel at high temperature is discussed. • Interactions between {001} dislocations and {110} irradiation loops are investigated in UO 2. • Helical turn configurations are the strongest pinning reactions identified. • DDD simulations show the impact of irradiation loops on the mechanical response of UO 2. • Loop drag and shovelling constrain the defect microstructure and the stress response. [ABSTRACT FROM AUTHOR]

We present the design, optical characterization and full-system modeling of a novel 6-focus, high-concentration photovoltaic-thermal solar polygeneration system, aiming at an energy-efficient and cost-effective utilization of the solar resource. Essential to this system is a compact, modular solar dish concentrator design optimized for mass-production, structural rigidity, and scalability, with a high geometric concentration ratio of 1733× at each of its six receivers. Every receiver comprises 36 triple-junction CPV cells, interconnected in a unique hybrid parallel-serial scheme that mitigates mismatch losses caused by non-uniform irradiance distributions. Cogeneration is enabled by using high-performance microchannel heat exchangers, allowing the extraction of low grade heat for secondary thermal processes. The tested prototype achieves an average solar radiative flux of 1374 suns on each of the receivers. By optimizing several design parameters, the CPV-thermal system can deliver a solar-to-electricity conversion efficiency of 28.5% in PV-only mode and 26.6% in cogeneration mode while extracting heat at 89.8 °C, and a power of 12.1 kW el and 11.3 kW el /21.5 kW th respectively, matching the performance of state of the art CPV commercial systems, while striving towards a reduction of the investment costs. [ABSTRACT FROM AUTHOR]

We propose a facile, novel concept of mass transfer enhancement in flow batteries based on electrolyte guidance in rationally designed corrugated channel systems. The proposed fluidic networks employ periodic throttling of the flow to optimally deflect the electrolytes into the porous electrode, targeting enhancement of the electrolyte-electrode interaction. Theoretical analysis is conducted with channels in the form of trapezoidal waves, confirming and detailing the mass transport enhancement mechanism. In dilute concentration experiments with an alkaline quinone redox chemistry, a scaling of the limiting current with Re 0.74 is identified, which compares favourably against the Re 0.33 scaling typical of diffusion-limited laminar processes. Experimental IR-corrected polarization curves are presented for high concentration conditions, and a significant performance improvement is observed with the narrowing of the nozzles. The adverse effects of periodic throttling on the pumping power are compared with the benefits in terms of power density, and an improvement of up to 102% in net power density is obtained in comparison with the flow-by case employing straight parallel channels. The proposed novel concept of corrugated fluidic networks comes with facile fabrication and contributes to the improvement of the transport characteristics and overall performance of redox flow battery systems. [ABSTRACT FROM AUTHOR]

Recent years have witnessed a remarkable reduction in solar-panel costs, such that low-efficiency, low-cost photovoltaics (PV) currently prevail over more complex, high-efficiency technologies. Although solar-energy-generating installations provide a renewable energy source often considered emission-free, a number of externalities are frequently ignored that favor technologies with a reduced efficiency as long as they are available at lower cost. Whenever PV systems are installed, the absorption properties of the surface are changed and less sunlight from the Earth’s surface is reflected into space. By including this radiative forcing in the form of the Earth’s surface reflection coefficient albedo (α), we take these externalities into consideration in the overall equivalent global warming potential (GWP) of a PV system. Three different effects need to be considered when changing the absorption properties of the Earth’s surface: (1) global albedo impact, (2) regional atmospheric heat islands, and (3) locally heated surfaces. The unintended radiative forcing adversely affects the net efficiency of building-integrated solar installations in warm urban climates, as more energy is required for cooling to ensure human comfort. The total GWP of four different PV technologies was examined for three different urban climates, temperate, moderate, and warm. To minimize the system energy payback time (EPBT) it is most sensible to install high-efficiency solar-energy systems outside cities and urban developments in locations with high annual irradiance. Only when taking radiative forcing into environmental and economic considerations is it expected that solar-technology development will correct its trajectory away from low-cost systems and toward high-efficiency installations with lower overall GWP. [ABSTRACT FROM AUTHOR]

Membraneless flow cells for electrochemical energy conversion exploit the laminarity of microscale flows to avoid undesirable mixing of reactants. To increase the performance of microfluidic redox flow cells we employ herringbone-inspired flow promoters, thereby increasing convection of each individual species to the electrodes, while minimizing reactant mixing. Polarization curves from electrochemical discharge measurements with a dilute anthraquinone/iron redox system reveal that the presence of flow promoters substantially boosts device performance. Mass transfer enhancement for devices with flow promoters is demonstrated through both higher limiting currents and increased power density; the former is more than double compared to a plain reference microchannel for Reynolds numbers of Re >155. The chaotic mixing effect induced by the flow promoters also becomes apparent in the scaling regimes, the limiting currents are proportional to Re 0.58 instead of Re 1/3 (as for purely laminar flow). Further, we quantify the area specific resistance (ASR) of the electrolyte in our membraneless devices finding a reduction of more than one order of magnitude compared to the ASR of conventional membranes employed in redox flow cells. Overcoming mass transfer limitations, this work highlights the necessity of passive mixers in significantly raising the performance of microfluidic flow cells. [ABSTRACT FROM AUTHOR]