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Controlling distortion is of key importance during the case hardening process for the production of automotive and non-automotive metallic components. By effective control of distortion and the variation of distortion, significant costs in post heat treatment machining processes can be avoided. In some cases it is even possible to eliminate all post-machining. In other cases it may be possible to avoid the press-quenching of individual components, resulting in huge cost-benefits. A recently introduced new vacuum furnace design allows the treatment of small batches in a single layer of parts (“2D-treatment”) which allows for easy automated loading and unloading of the fixture-trays. By using the small batch concept, a continuous flow of parts can be established (“One Piece Flow”). There is no need to wait until enough parts are collected to build a large batch with multiple layers (“3D-batch”). This compact furnace unit can be implemented into the heart of the production chain and provides heat-treatment processes which can be fully synchronized with the green and hard machining-operations. When performing case hardening, the components are Low Pressure Carburized (LPC) at high temperatures (1050 °C) followed by gas quenching. The treatment in single layers offers an optimum in quality regarding: temperature homogeneity, quench homogeneity and distortion control. Typical components for this technology come from the automotive, aerospace and tool industry. The directly following contribution in this Journal (A. Schüler et al., p. 90–98)shows more results achieved with this technology on selected truck-components such as gears and sliding-sleeves.

Thirty‐two accelerometers were deployed in the Livermore Valley, California, for approximately one year to study sedimentary basin effects. Many local and near‐regional earthquakes were recorded, including the 24 August 2014 M w 6.0 Napa, California, earthquake. The resulting ground‐motion data set is used to quantify the seismic response of the Livermore basin, a major structural depression in the California Coast Range Province bounded by active faults. Site response is calculated by two methods: the reference‐site spectral ratio method and a source‐site spectral inversion method. Longer‐period (≥1 s) amplification factors follow the same general pattern as Bouguer gravity anomaly contours. Site response spectra are inverted for shallow shear‐wave velocity profiles, which are consistent with independent information. Frequency–wavenumber analysis is used to analyze plane‐wave propagation across the Livermore Valley and to identify basin‐edge‐induced surface waves with back azimuths different from the source back azimuth. Finite‐element simulations in a 3D velocity model of the region illustrate the generation of basin‐edge‐induced surface waves and point out strips of elevated ground velocities along the margins of the basin. Online Material: Figures comparing 5% damped acceleration response spectra for data and synthetics.

It was hypothesized that the Malabar grouper Ephinephelus malabaricus larvae have developed search patterns adapted to the distribution of their prey to maximise their net energy intake per unit time. Analysis of the swimming behaviour of E. malabaricus larvae in both the presence and absence of Artemia sp. nauplii is presented to test this hypothesis. A method derived from turbulence studies (the moment function of the displacements) was used to characterize the behaviour. The results revealed that larval swimming pattern was multifractal (intermittent and long-range-correlated) and isotropic (i.e. uniform in all directions) in the presence of prey, but multifractal and anisotropic (i.e. more frequent long displacement on the vertical axis) in the absence of prey. It is suggested that the search behaviour observed in the absence of prey is an adaptive response to prey distribution pattern, which is often characterised by multifractality and anisotropy (i.e. larger patches on the horizontal axes). In the presence of prey, E. malabaricus shifted to intensive search behaviour. Other possible contributors to the observed patterns are discussed. It is concluded that multifractality and anisotropy of swimming patterns observed in the experiment are mainly explained in an optimal foraging theory framework.

On 25 May 2014, a rain-on-snow–induced rock avalanche occurred in the West Salt Creek valley on the northern flank of Grand Mesa in western Colorado (United States). The avalanche mobilized from a preexisting rock slide in the Green River Formation and traveled 4.6 km down the confined valley, killing three people. The avalanche was rare for the contiguous United States because of its large size (54.5 Mm 3 ) and high mobility (height/length = 0.14). To understand the avalanche failure sequence, mechanisms, and mobility, we conducted a forensic analysis using large-scale (1:1000) structural mapping and seismic data. We used high-resolution, unmanned aircraft system imagery as a base for field mapping, and analyzed seismic data from 22 broadband stations (distances

We evaluate the effect of chain length for a series of alkyl sulfonic acid additives on Cu electrodeposition by using a combination of electrochemical and Raman spectroscopic methods. The combination of these methods suggests that effective Cu electrodeposition acceleration processes require: 1) direct tethering of mercaptoalkylsulfonate species to the electrode, 2) partial desolvation of Cu2+ by the sulfonate group to minimize its solvent reorganization energy, and 3) stabilization of Cu+ adjacent to the electrode surface by addition of halide. Finally, we use the cis-trans ratio idea developed for SPS to examine the effect of inhibitors on SPS activity. We also investigate the behavior of Cu plating bath suppressor additives poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG) using normal Raman spectroscopy, surface-enhanced Raman spectroscopy (SERS), and electrochemical quartz crystal microbalance (QCM) measurements. Raman and SERS show a clear spectroscopic trend of increased intensity in higher wavenumber modes in the CH stretching region as the environment is changed from pure material to solution to surface for both PEG and PPG. The spectral changes associated with PEG are larger than those associated with PPG, suggesting that the relatively more hydrophilic PEG undergoes more conformational changes upon surface association relative to the more hydrophobic PPG. In the presence of Cl-, PPG forms a denser surface layer compared to PEG on a Cu underpotential deposition (UPD) layer on Au. These differences are consistent with the increased hydrophobicity of PPG relative to PEG.

This paper presents a new actuator designed to produce forces under short stroke displacements. Two variants of the prototype have been manufactured using Multi-Material Additive Manufacturing process, based on a flexible origami-inspired architecture. The structure consists of an airtight chamber constituted by rigid plates combined with flexible hinges and surfaces in order to allow the generation of motion. We propose several insights on integration issues such as limited material resistance and maximum range of motion. Both versions of the prototype are then tested to assess their performances for single strokes and cyclic loading.

Results from twenty‐two airborne field campaigns, including more than ten million high‐resolution particle images collected in cirrus formed in situ and in convective anvils, are interpreted in terms of particle shapes and their potential impact on radiative transfer. Emphasis is placed on characterizing ice particle shapes in Tropical Maritime and Mid‐Latitude Continental anvil cirrus, as well as in cirrus formed in situ in the upper troposphere, and subvisible cirrus in the upper tropical troposphere layer. There is a distinctive difference in cirrus ice particle shapes formed in situ compared to those in anvils that are generated in close proximity to convection. More than half the mass in cirrus formed in situ are rosette‐shapes (polycrystals and bullet rosettes). Cirrus formed from fresh convective anvils is mostly devoid of rosette‐shaped particles. However, small frozen drops may experience regrowth downwind of an aged anvil in a regime with RHice > ~ 120%, and then grow into rosette shapes. Identifiable particle shapes in Tropical Maritime anvils that have not been impacted by continental influences typically contain mostly single plate‐like and columnar crystals and aggregates. Mid‐Latitude Continental anvils contain single rimed particles, more and larger aggregates with riming, and chains of small ice particles when in a highly electrified environment. The particles in subvisible cirrus are < ~ 100 μm and quasi‐spherical with some plates and rare trigonal shapes. Percentages of particle shapes and power laws relating mean particle area and mass to dimension are provided to improve parameterization of remote retrievals and numerical simulations.

The increase of pluvial flooding has long been discussed to be a most probable outcome of climate change. This has raised the question of necessary consequences in the design of urban drainage systems in order to secure adequate flood protection and resilience. Due to the uncertainties in future trends of heavy rainfall events, the awareness of remaining risks of extreme pluvial flooding needs to be roused at responsible decision makers and the public as well leading to the implementation of pluvial flood risk management (PFRM) concepts. The state of two core elements of PFRM in Germany are described here: flood hazard and risk evaluation and risk communication. In 2016 the guideline DWA-M 119 has been published to establish city-based PFRM concepts in specification of the European Flood Risk Management Directive (EU 2007). As core elements, the guidelines recommend a site-specific analysis and evaluation of flood hazards and potentials of flood damages to create flood hazard and flood risk maps. In the long run, PFRM needs to be established as a joint community effort and a requirement for more flood resilience. The risk communication within the administration and in the public requires a comprehensible characterization and classification of heavy rainfall to illustrate event extremity. The concept of a rainstorm severity index (RSI) instead of statistical rainfall parameters appears to be promising to gain a better perception by affected citizens and non-hydrology-experts as well. A methodical approach is described to specify and assign site-specific rainfall depths within the severity index scheme RSI12. This article is categorized under: Engineering Water > Sustainable Engineering of Water Engineering Water > Planning Water Engineering Water > Methods

The identification of flood hazards and flood risks (spatial overlay of flood hazards and potential damage) are basic tasks of flood risk management. Due to a lack of data for a comprehensive assessment of potential damage in urban areas, flood risks are often only determined for buildings (based on the building use from real estate cadastres). Therefore, building-related statements about flood hazards are required to assess flood risks. In practice, flood hazards for buildings are usually determined from results of hydrodynamic 2D surface runoff models using simple methods. These methods do not take into account the fact that building structures in the model may differ from the data of the underlying cadastre. This is particularly relevant for grid-based models, where the structure of a building in the model depends on the resolution of the calculation grid. To avoid inaccuracies inherent to these methods, we introduce a new algorithm. It first evaluates the results of a grid-based model on the basis of the calculation grid and then links them to the underlying building structures from the cadastre. Thus, differences between the rasterized buildings and their structure in the cadastre are taken into account. In addition we investigate the dependence of the results of the algorithm on the resolution of the calculation grid.

The combination of dissimilar metals can result in corrosion due to galvanic effects. These are caused by differences in their electrode potentials. The spread difference between these potentials is the driving force for galvanic corrosion. Literature data usually refer to either standard conditions or aerated sea water at ambient temperature. However, the actual electrode potentials are influenced by a variety of factors such as temperature, pH, dissolved gases and salts, flow rates, scale formation, etc. For conditions encountered in the oil and gas industry, there are hardly any data about electrode potentials available. The aim of this work is to create a practical galvanic series under typical upstream conditions for standard oil country tubular goods (OCTG) steels, corrosion resistant alloys (CRA) as well as the gasket material graphite. The following materials were selected for the tests, which are considered as representative for downhole and topsides equipment: J55, L80 Type 1, X52, Cr13, 316Ti, 2205, 904L and Graphite. The electrode potentials and polarization resistances of the selected materials were measured in synthetic formation water with dissolved carbon dioxide (CO2) at temperatures between 22 and 130 °C. To account for the influence of bicarbonate and acetic acid these species were added in some of the tests. In order to also identify overpotential effects the electric galvanic currents were determined between coupled dissimilar materials in the described media at different temperatures by electrochemical noise measurements (CoulCount-Method). For comparison, actual corrosion rates of dissimilar material couples were measured gravimetrically. The results exhibit the influences of temperature, bicarbonate and acetic acid on the electrode potential of each material. Galvanic corrosion effects are observed between CRAs and OCTG. The highest galvanic corrosion occurs between graphite and OCTG and is also distinct between graphite and CRAs. Temperature has a strong influence on the galvanic corrosion. At high temperatures, galvanic corrosion effects occur also in couples of different CRAs. The results show a good agreement between the measured electrode potentials, the results of electrochemical noise measurements and the gravimetric corrosion tests. This work provides a practical galvanic series for materials and conditions that are usually encountered in the upstream oil and gas industry. Based on the results of the work presented it is possible to rate the galvanic material behavior under similar conditions. Being one of the first publications in this field of application, it represents a reference for material selection, engineering and failure analysis.

Este estudio proporciona de manera general el impacto de las Partículas Absorbentes de Luz (LAPs, por sus siglas en inglés) en la nieve superficial de los glaciares de la Cordillera Blanca, dando prioridad al carbono negro (CN), ya que representa el material particulado PM más común de los contaminantes atmosféricos proveniente de la quema de pastos, la quema de residuos agrícolas, el uso de biomasa para cocinar, el parque automotor y toda actividad humana que involucre la combustión de combustibles fósiles. La presencia de la LAPs sobre los glaciares explicaría en parte el acelerado retroceso de los glaciares, debido a que involucra el aumento de la tasa de fusión. Aquí informamos sobre las concentraciones de LAPs en la nieve superficial de los glaciares Yanapaccha, Shallap, Tocllaraju y Vallunaraju durante la ocurrencia de El Niño y El Niño Costero. Entre 2016 y 2017 se recolectaron muestras de nieve de forma mensual en los glaciares a una altitud aproximada de 5000 msnm. Estas muestras fueron fundidas y filtradas en el campo y luego se analizaron bajo el método de calentamiento por absorción de luz (LAHM, por sus siglas en inglés) para determinar las concentraciones de carbono negro efectivo (CNe). Este método se basa en la medición de la capacidad de las partículas 2.5 retenidas en los filtros para absorber la luz visible, siendo el carbono negro un tipo de LAP con un alto poder para absorber la luz solar a diferencia del polvo mineral. Los resultados de LAHM se utilizaron para estimar la disminución del albedo mediante el programa de simulación SNICAR. Asimismo, se utilizaron datos de radiación solar registrados en las cercanías de los glaciares, con el fin de estimar la cantidad de nieve fundida a causa del carbono negro en kg/m2 o su equivalente en mm de agua (mm w.e.). Los resultados muestran una mayor concentración de carbono negro durante El Niño (1047.07 y 1091.75 ng/g) que durante El Niño Costero (780.67 y 706.40 ng/g), fundiéndose un total de 3897.56 kg/m2 de nieve durante El Niño y 1884.03 kg/m2 durante El Niño Costero. En cuanto a la reflectancia de la nieve estimamos una reducción del 15% en promedio durante el período de estudio.

The temporal statistics of incompressible fluid velocity and passive scalar fields in developed turbulent conditions is investigated by means of direct numerical simulations along the trajectories of self-propelled point-like probes drifting in a flow. Such probes are characterised by a propulsion velocity which is fixed in intensity and direction; however, like vessels in a flow they are continuously deviated by their intended course as the result of local sweeping of the fluid flow. The recorded time-series by these moving probes represent the simplest realisation of transect measurements in a fluid flow environment. We investigate the non trivial combination of Lagrangian and Eulerian statistical properties displayed by the transect time-series. We show that, as a result of the homogeneity and isotropy of the flow, the single-point acceleration statistics of the probes follows a predictable trend at varying the propulsion speed, a feature that is also present in the scalar time-derivative fluctuations. Further, by focusing on two-time statistics we characterize how the Lagrangian-to-Eulerian transition occurs at increasing the propulsion velocity. The analysis of intermittency of temporal increments highlights in a striking way the opposite trends displayed by the fluid velocity and passive scalars., Comment: 12 pages, 7 figures + supplementary

Es wurden Checklisten zur anlagenspezifischen Identifizierung von Optimierungspotenzialen für Kläranlagen mit Faulung entwickelt. Wesentliche Ziele sind die energetische Optimierung der Anlagen, die Reduzierung der Schlammmengen für die Entsorgung und die Sicherstellung der Abwasserreinigung auf einem hohen Niveau. Ein Überblick über die Ansätze zur Optimierung bestehender Faulungsanlagen, die Checklisten sowie Ergebnisse bei deren Anwendung wird gegeben.

Turbulent characteristics in the atmospheric surface layer are investigated using a data-driven method, Hilbert spectral analysis. The results from empirical mode decomposition display a set of intrinsic mode functions whose characteristic scales suggest a dyadic filter-bank property. It can be concluded from the joint probability density function of the intrinsic mode functions that the turbulent properties are totally different under different stratifications: the amplitudes (or energies) are arranged according to the stability parameter for stable conditions, but tend to cluster randomly for unstable cases. The intermittency analyses reveal that second-order Hilbert marginal spectra display a power-law behaviour in the inertial subrange, and that the scaling exponent functions deviate from the theoretical values due to the strong intermittency in the stable boundary layer.

This article is a review of the science goals and activities initiated within the framework of the Pollution and its Impacts on the South American Cryosphere (PISAC) initiative. Air pollution associated with biomass burning and urban emissions affects extensive areas of South America. We focus on black carbon (BC) aerosol and its impacts on air quality, water availability, and climate, with an emphasis on the Andean cryosphere. BC is one of the key short-lived climate pollutants that is a topic of growing interest for near-term mitigation of these issues. Limited scientific evidence indicates that the Andean cryosphere has already responded to climate change with receding glaciers and snow cover, which directly affect water resources, agriculture, and energy production in the Andean region of South America. Despite the paucity of systematic observations along the Andes, a few studies have detected BC on snow and glaciers in the Andes. These, in addition to existing and projected emissions and weather patterns, suggest a possible contribution of BC to the observed retreat of the Andean cryosphere. Here we provide an overview of the current understanding of these issues from scientific and policy perspectives, and propose strategic expansions to the relevant measurement infrastructure in the region.

We investigate the mechanism of 3-mercapto-1-propanesulfonate (MPS) acceleration of Cu electrodeposition in the presence of Cl– through comparison with the inactive but related model compounds 1-butanesulfonate and 1-butanethiol (BuSH). In situ shell-isolated nanoparticle-enhanced Raman spectroscopy was used to evaluate these additives as a function of potential. MPS adsorbs to the Cu electrode in the presence of Cl– through the thiol functional group. Density functional theory calculations reveal that the adsorption of thiol has a depolarizing effect on the strength of the interaction between adsorbed Cl– and the electrode surface, the consequences of which are observed spectroscopically. The sulfonate moiety does not interact directly with the electrode. However, cyclic voltammetry used to assess the permeability of adsorbed MPS and BuSH adlayers indicates that the sulfonate group has a more direct role in Cu deposition beyond simple disruption of the surface layer.

To develop a simple approach to increase titers of transient gene expression in CHO cells without relying on host cell line engineering as recent reports suggest that for PEI-mediated transfections, under optimized conditions, DNA delivery into cells and nuclei is not the limiting factor. N, N-Dimethyl acetamide (DMA) was utilized to enhance transcription. To target post-transcriptional events, we evaluated the co-expression of various genes involved in the unfolded protein response, namely XBP1S, ATF4, CHOP and HSPA5. XBP1S overexpression led to a 15–85 % increase in titer for multiple therapeutic proteins. Mechanistic studies confirmed that addition of 0.125 % DMA increased transgene mRNA levels as expected. However, overexpression of XBP1S had no effect on transgene mRNA levels, indicating that it influenced post-transcriptional events. Since DMA and XBP1S targeted different pathways, the combination of the two approaches led to an additive improvement in protein titer (150–250 % titer increase). Transcriptional and post-transcriptional pathways of transient gene expression can be targeted to increase titers without resorting to host cell line engineering in a simple, short, 7 day production process.

Predicted demographic, climatic and socio-economic changes will require adaptations of existing water supply and wastewater disposal systems. Especially in rural areas, these new challenges will affect the functionality of the present systems. This paper presents a joint interdisciplinary research project with the objective of developing an innovative software-based optimization and decision support system for the implementation of long-term transformations of existing infrastructures of water supply, wastewater and energy. The concept of the decision support and optimization tool is described and visualization methods for the presentation of results are illustrated. The model is tested in a rural case study region in the Southwest of Germany. A transformation strategy for a decentralized wastewater treatment concept and its visualization are presented for a model village.

In future, an additional potential of control reserve as well as storage capacities will be necessary to compensate fluctuating energy generators such as wind and solar power plants. The core objective of the joint research project “arrivee” is the integration of widely available wastewater treatment plants (WWTP) with anaerobic sludge digestion into an optimized control reserve and storage concept. Therefore the excellent technical conditions of those plants such as combined heat and power (CHP) units as well as gas storage units will be used. By means of analyzing energy consumption and production processes of existing WWTPs the potential to provide ancillary services for energy grids is investigated. Using a mathematical model of an existing WWTPs the effects of external interventions for the supply of ancillary services under different conditions are tested. Therefore, different processes will be analyzed in detail. The integration of WWTPs into a virtual power plant (VPP) is mandatory because a single plant can’t provide enough capacity to participate on energy markets. The initial results present a theoretical potential of control reserve of WWTPs in Germany focusing on a CHP/gas unit of a magnitude of 300 MW el . This results show a substantial potential of WWTPs to provide ancillary services, by reshaping the existing infrastructure in a sustainable, ecological and economic way. This may contribute significantly to a stable operation of energy grids and to further integration of renewable energy sources in the frame of energy system transition.

A nesting trace preserved in alluvial floodplain deposits in the Upper Cretaceous Two Medicine Formation at the Willow Creek anticline in north-central Montana contains four crushed theropod eggs referable to the oospecies Continuoolithus canadensis. These eggs immediately overlie the lower surface of a 35-cm-long × 7-cm-thick, dark-green mudstone lens, surrounded by reddish-purple mudstone. The long axes of three eggs are parallel to one another and to the lower boundary of the lens, whereas the fourth egg lies at a 30° angle to the others. A thin, 1-cm-thick organic horizon overlies the eggs, suggesting they were buried with some vegetation. Geometric modeling of the slightly asymmetrical C. canadensis eggs yields a volume and mass of approximately 194 cm3 and 205 g for each egg. This method provides a more accurate estimation for the surface area than allometric equations that are based on modern bird eggs because of the elongate shape of many non-avian theropod eggs. Pore density and water vapor conductance (GH2O) calculated from one egg in the trace and five additional C. canadensis eggs from the Willow Creek anticline vary across three regions. High, moderate, and very low GH2O characterize the equatorial zone, blunt, and tapering poles, respectively. The average GH2O for all eggs exceeds that of an avian egg of similar mass by 3.9×, thus supporting sedimentologic evidence of substrate burial during incubation.

The purpose of this study is to develop a decision support system (DSS) for the technical sustainability assessment of water distribution systems (WDSs). The technical sustainability is assessed based on the sustainability index methodology using reliability, resiliency, and vulnerability as performance criteria. These performance criteria are visualized by the DSS combining several visualization techniques to improve the raw data readability and the effectiveness of the decision-making process. The technical sustainability of the existing WDS is assessed using the sustainability index methodology and two alternative scenarios are proposed to improve the sustainability. The “new pump” scenario is based on adding network components. The second scenario is based on using reclaimed water for non-potable water demand and fire flow. The results show that the DSS is effective to illustrate time-dependent variables in the WDS and that the sustainability index methodology is a credible approach to compare scenarios and to identify problematic locations.

We consider here the dynamics of two polychaete populations based on a 20 yr temporal benthic survey of two muddy fine sand communities in the Bay of Morlaix, Western English Channel. These populations display high temporal variability, which is analyzed here using scaling approaches. We find that population densities have heavy tailed probability density functions. We analyze the dynamics of relative species abundance in two different communities of polychaetes by estimating in a novel way a "mean square drift" coefficient which characterizes their fluctuations in relative abundance over time. We show the usefulness of using new tools to approach and model such highly variable population dynamics in marine ecosystems.

We consider here pH and temperature fluctuations in marine waters, recorded at fixed points using high resolution automatic devices. We analyze time series coming from 4 monitoring stations located along French coast: one station is situated in the coastal area off Boulogne-sur-mer (Eastern English Channel) and 3 stations in the Bay of Seine. All these pH time series reveal large fluctuations at all scales similar to turbulent temperature fluctuations. We compare the pH and temperature time series through Fourier spectral analysis methods: spectra, compensated spectra, cospectra. We find good scaling properties of pH fluctuations, with power spectral slopes close to 1.5 for marine stations and 1.2 for the estuarine station. These analyses show that pH fluctuations in marine waters are strongly influenced by turbulent hydrodynamical transport, and may be considered as a turbulent active scalar.

International audience; The growing interest in soft robots comes from the new possibilities offered by these systems to cope with problems that cannot be addressed by robots built from rigid bodies. Many innovative solutions have been developed in recent years to design soft components and systems. They all demonstrate how soft robotics development is closely dependent on advanced manufacturing processes. This review aims at giving an insight on the current state of the art in soft robotics manufacturing. It first puts in light the elementary components that can be used to develop soft actuators, whether they use fluids, shape memory alloys, electro-active polymers or stimuli-responsive materials. Other types of elementary components, such as soft smart structures or soft-rigid hybrid systems, are then presented. The second part of this review deals with the manufacturing methods used to build complete soft structures. It includes molding, with possibly reinforcements and inclusions, additive manufacturing, thin-film manufacturing, shape deposition manufacturing, and bonding. The paper conclusions sums up the pros and cons of the presented techniques, and open to developing topics such as design methods for soft robotics and sensing technologies.

Fractal phenomena can be found in numerous scientific areas including neuroscience. Fractals are structures, in which the whole has the same shape as its parts. A specific structure known as pink noise (also called fractal or 1/f noise) is one key fractal manifestation, exhibits both stability and adaptability, and can be addressed via the Hurst exponent (H). FMRI studies using H on regional fMRI time courses used fractality as an important characteristic to unravel neural networks from artificial noise. In this fMRI-study, we examined 103 healthy male students at rest and while performing the 5-choice serial reaction time task. We addressed fractality in a network associated with waiting impulsivity using the adaptive fractal analysis (AFA) approach to determine H. We revealed the fractal nature of the impulsivity network. Furthermore, fractality was influenced by individual impulsivity in terms of decreasing fractality with higher impulsivity in regions of top-down control (left middle frontal gyrus) as well as reward processing (nucleus accumbens and anterior cingulate cortex). We conclude that fractality as determined via H is a promising marker to quantify deviations in network functions at an early stage and, thus, to be able to inform preventive interventions before the manifestation of a disorder.

We consider Lagrangian velocity differences of zooplankters swimming in still water and in turbulence. Using cumulants, we quantify the intermittency properties of their motion recorded using three-dimensional particle tracking velocimetry. Copepods swimming in still water display an intermittent behaviour characterized by a high probability of small velocity increments, and by stretched exponential tails. Low values arise from their steady cruising behaviour while heavy tails result from frequent relocation jumps. In turbulence, we show that at short time scales, the intermittency signature of active copepods clearly differs from that of the underlying flow, and reflects the frequent relocation jumps displayed by these small animals. Despite these differences, we show that copepods swimming in still and turbulent flow belong to the same intermittency class that can be modelled by a log-stable model with non-analytical cumulant generating function. Intermittency in swimming behaviour and relocation jumps may enable copepods to display oriented, collective motion under strong hydrodynamic conditions and thus, may contribute to the formation of zooplankton patches in energetic environments., The European Physical Journal E, 38 (10), ISSN:1292-8941, ISSN:1292-895X

A key ecological parameter for planktonic copepods studies is their interspecies encounter rate which is driven by their behaviour and is strongly influenced by turbulence of the surrounding environment. A distinctive feature of copepods motility is their ability to perform quick displacements, often dubbed jumps, by means of powerful swimming strokes. Such a reaction has been associated to an escape behaviour from flow disturbances due to predators or other external dangers. In the present study, the encounter rate of copepods in a developed turbulent flow with intensity comparable to the one found in copepods' habitat is numerically investigated. This is done by means of a Lagrangian copepod (LC) model that mimics the jump escape reaction behaviour from localised high-shear rate fluctuations in the turbulent flows. Our analysis shows that the encounter rate for copepods of typical perception radius of ~ {\eta}, where {\eta} is the dissipative scale of turbulence, can be increased by a factor up to ~ 100 compared to the one experienced by passively transported fluid tracers. Furthermore, we address the effect of introducing in the LC model a minimal waiting time between consecutive jumps. It is shown that any encounter-rate enhancement is lost if such time goes beyond the dissipative time-scale of turbulence, {\tau}_{\eta}. Because typically in the ocean {\eta} ~ 0.001m and {\tau}_{\eta} ~ 1s, this provides stringent constraints on the turbulent-driven enhancement of encounter-rate due to a purely mechanical induced escape reaction., Comment: 11 pages, 10 figures

Earthquake‐induced landslide (EQIL) inventories are essential tools to extend our knowledge of the relationship between earthquakes and the landslides they can trigger. Regrettably, such inventories are difficult to generate and therefore scarce, and the available ones differ in terms of their quality and level of completeness. Moreover, access to existing EQIL inventories is currently difficult because there is no centralized database. To address these issues, we compiled EQIL inventories from around the globe based on an extensive literature study. The database contains information on 363 landslide‐triggering earthquakes and includes 66 digital landslide inventories. To make these data openly available, we created a repository to host the digital inventories that we have permission to redistribute through the U.S. Geological Survey ScienceBase platform. It can grow over time as more authors contribute their inventories. We analyze the distribution of EQIL events by time period and location, more specifically breaking down the distribution by continent, country, and mountain region. Additionally, we analyze frequency distributions of EQIL characteristics, such as the approximate area affected by landslides, total number of landslides, maximum distance from fault rupture zone, and distance from epicenter when the fault plane location is unknown. For the available digital EQIL inventories, we examine the underlying characteristics of landslide size, topographic slope, roughness, local relief, distance to streams, peak ground acceleration, peak ground velocity, and Modified Mercalli Intensity. Also, we present an evaluation system to help users assess the suitability of the available inventories for different types of EQIL studies and model development.

In the future, an additional potential of control reserve as well as storage capacities will be required to compensate fluctuating renewable energy availability. The operation of energy systems will change and flexibility in energy generation and consumption will rise to a valuable asset. Wastewater treatment plants (WWTPs) are capable of providing the flexibility needed, not only with their energy generators but also in terms of their energy consuming aggregates on the plant. To meet challenges of the future in regard to energy purchase and to participate in and contribute to such a volatile energy market, WWTPs have to reveal their energetic potential as a flexible service provider. Based on the evaluated literature and a detailed analysis of aggregates on a pilot WWTP an aggregate management has been developed to shift loads and provide a procedure to identify usable aggregates, characteristic values and control parameters to ensure effluent quality. The results show that WWTPs have a significant potential to provide energetic flexibility. Even for vulnerable components such as aeration systems, load-shifting is possible with appropriate control parameters and reasonable time slots without endangering system functionality.

Colloque avec actes et comité de lecture. Internationale.; International audience; Les copépodes sont des crustacés zooplanctoniques très abondants dans les écosystèmes aquatiques. Ils sont un élément important de la chaîne alimentaire, reliant le phytoplancton et les larves de poisson. Les copépodes peuvent nager, et leur nage comporte entre autres des sauts puissants et localisés, souvent utilisés dans le milieu aquatique, pour échapper à leurs prédateurs. Ce comportement de nage, en relation en particulier avec les gradients locaux du champ de vitesse dans leur environnement proche, fait que les copépodes ne peuvent pas être considérés comme des traceurs passifs de l'écoulement. L'influence de ces sauts sur leur répartition spatiale est encore très mal connue. Les travaux présentés dans cette communication font partie d'un travail de thèse soutenue en octobre 2016. Il s'agit de placer des copépodes virtuels (un modèle lagrangien de copépodes) dans un écoulement de simulation numérique directe (DNS) de la turbulence, et de considérer numériquement l'influence du comportement de saut sur la répartition des copépodes dans l'écoulement. Les copépodes virtuels sont placés dans une turbulence homogène et isotrope de nombre de Reynolds (basé sur l'échelle de Taylor) de 80. Ils sont advectés comme des particules passives lagrangiennes, avec des sauts déterminés par la valeur du module du tenseur de déformation dans leur environnement immédiat. Plusieurs paramètres rentrent en compte: le seuil pour déclencher les sauts, la vitesse instantanée des sauts, l'orientation des sauts et le temps de latence entre deux sauts successifs. Différentes simulations sont réalisées, avec 256,000 particules. La répartition spatiale est étudiée via la dimension de corrélation des copépodes; on obtient, pour certaines valeurs des paramètres, une accumulation, ou concentration préférentielle (preferential concentration) assez marquée. L'effet de cette accumulation locale est potentiellement très important écologiquement: cela peut très fortement augmenter le taux de rencontre entre copépodes, et donc l'efficacité de la reproduction. Ces résultats, et leurs implications écologiques, seront discutés dans cette présentation.

Quark nuggets are theoretical objects composed of approximately equal numbers of up, down, and strange quarks and are also called strangelets and nuclearites. They have been proposed as a candidate for dark matter, which constitutes about 85% of the universe's mass and which has been a mystery for decades. Previous efforts to detect quark nuggets assumed that the nuclear-density core interacts directly with the surrounding matter so the stopping power is minimal. Tatsumi found that quark nuggets could well exist as a ferromagnetic liquid with an approximately 10 trillion Tesla magnetic field. We find that the magnetic field produces a magnetopause with surrounding plasma, as the earth's magnetic field produces a magnetopause with the solar wind, and substantially increases their energy deposition rate in matter. We use the magnetopause model to compute the energy deposition as a function of quark-nugget mass and to analyze testing the quark-nugget hypothesis for dark matter by observations in the air, water, and land. We conclude the water option is most promising., 14 pages, 10 figures, This is a post-peer-review, pre-copy-edit version of an article published in Scientific Reports. The final authenticated version is available open source online at: https://dx.doi.org/10.1038/s41598-017-09087-3 or https://www.nature.com/articles/s41598-017-09087-3

This study is the first in situ work comparing rapid light curves (RLC) and non-sequential steady-state light curves (N-SSLC) in their efficiency to characterize phytoplankton photosynthetic activity and acclimation status. Measurements were carried out at two time scales (daily and annual) using the Pulse Amplitude Modulated fluorometry on samples taken in the coastal waters of a macrotidal ecosystem (the Strait of Dover, eastern English Channel). RLC and N-SSLC were compared under a wide range of environmental conditions and phytoplankton composition in order to define the best methodology to accurately capture short and long-term adjustments in the functioning of the photosynthetic apparatus. The relationships between the photosynthetic parameters extracted from RLC and N-SSLC were also studied to evaluate the possibility to use RLC to predict N-SSLC photosynthetic parameters and thus obtaining the acclimation status at steady state. At daily scale, the maximum electron transport rate and light saturation coefficient resulting from RLC (respectively, ETRm_RLC and E k_RLC) were found to follow more closely short-term environmental light variations than ETRm and E k resulting from N-SSLC (ETRm_N-SSLC and E k_N-SSLC) did. RLC were thus able to detect rapid changes in photosynthetic activity that would have been overlooked with N-SSLC measurements. At annual scale, few differences were found between RLC and N-SSLC. Variations of ETRm and α derived from RLC and N-SSLC were very similar but absolute values were lower for RLC measurements. Because, at daily scale, RLC better capture the short-term changes in photosynthetic activity than N-SSLC do, using RLC to predict N-SSLC photosynthetic parameters and getting information about steady-state acclimation status is not possible at this time scale. However, this can be done at seasonal scale.

In recent years several local extrema based methodologies have been proposed to investigate either the nonlinear or the nonstationary time series for scaling analysis. In the present work we study systematically the distribution of the local extrema for both synthesized scaling processes and turbulent velocity data from experiments. The results show that for the fractional Brownian motion (fBm) without intermittency correction the measured extremal point density (EPD) agrees well with a theoretical prediction. For a multifractal random walk (MRW) with the lognormal statistics, the measured EPD is independent with the intermittency parameter $\mu$, suggesting that the intermittency correction does not change the distribution of extremal points, but change the amplitude. By introducing a coarse-grained operator, the power-law behavior of these scaling processes is then revealed via the measured EPD for different scales. For fBm the scaling exponent $\xi(H)$ is found to be $\xi(H)=H$, where $H$ is Hurst number, while for MRW $\xi(H)$ shows a linear relation with the intermittency parameter $\mu$. Such EPD approach is further applied to the turbulent velocity data obtained from a wind tunnel flow experiment with the Taylor scale $\lambda$ based Reynolds number $Re_{\lambda}= 720$, and a turbulent boundary layer with the momentum thickness $\theta$ based Reynolds number $Re_{\theta}= 810$. A scaling exponent $\xi\simeq 0.37$ is retrieved for the former case. For the latter one, the measured EPD shows clearly four regimes, which agree well with the four regimes of the turbulent boundary layer structures., Comment: 26 pages with 19 figures

International audience; The correlation between the flow turbulence and the performances of a ma- rine current turbine is studied. First, the incoming flow encountered in the flume tank is characterized in the framework of fully developed turbulent cascades in the inertial range. The Reynolds number, the Kolmogorov dissipation scale and the integral scale, are estimated from flow measurements. The intermittency of the turbulence is characterized in the lognormal multifractal framework, and the influence of the turbulent flow on the turbine power is assessed. The rotor speed control unit characteristics used for the turbine regulation induces non-negligible effects on the turbine behavior under fluctuations loads. Even if the power spectrum does not reveal any scale invariance, a multiscale analysis allows us to show the correlations between the turbulence time se- ries and the power produced. The classical Mean Square Coherency function shows that for scales larger than 10 seconds, the upstream velocity and power have large correlations. In the framework of the Empirical Mode Decomposition method, such correlations are studied using the time-dependence intrinsic corre- lation analysis method. This method allows to zoom into time-frequency scales where the flow perturbations induced some modifications in power production

International audience; The CASES-99 experimental data are used to analyze turbulence behaviour under a range of stable conditions using an adaptive method based on Hilbert spectral analysis. The characteristic scales of intrinsic mode functions vary between different stratifications. The second-order Hilbert marginal spectra display clear separation between fine-scale turbulence and large-scale motions. After removing the large-scale motions, the statistical characteristics of the reconstructed signals confirm the distinction of different stratifications in the fine-scale range. The correlation coefficient analyses reveal that the Hilbert spectral analysis method separates turbulence from large-scale motions in the stable boundary layer.

Generating purified protein for GLP toxicology studies (GLP-Tox) represents an important and often rate limiting step in the biopharmaceutical drug development process. Toxicity testing requires large amounts of therapeutic protein (>100 g), typically produced in a single 500-2,500 L bioreactor, using the final CHO clonally derived cell line (CDCL). One approach currently used to save time is to manufacture GLP-Tox material using pools of high-producing CHO CDCLs instead of waiting for the final CDCL. Recently, we reported CHO pools producing mAb titers >7 g/L using piggyBac-mediated gene integration (PB CHO pools). In this study, we wanted to leverage high titer PB CHO pools to produce GLP-Tox material. A detailed product quality attribute (PQA) assessment was conducted comparing PB CHO pools to pooled Top4 CDCLs. Four mAbs were evaluated. First, we found that PB CHO pools expressed all four mAbs at high titers (2.8-4.4 g/L in shake flasks). Second, all four PB CHO pools were aged to 55 generations (Gen). All four PB CHO Pools were found to be suitable over 55 Gen. Finally, we performed bioreactor scale-up. PB CHO pool titers (3.7-4.8 g/L) were similar or higher than the pooled Top 4 CDCLs in 5 L bioreactors (2.4-4.1 g/L). The PQAs of protein derived from PB CHO pools were very similar to pooled Top 4 CHO CDCLs according to multiple orthogonal techniques including peptide mapping analysis. Taken together, these results demonstrate the technical feasibility of using PB CHO pools to manufacture protein for GLP-Tox. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1436-1448, 2017.

To provide a better representation of natural ice clouds, a novel ice cloud model is developed by assuming an ice cloud to consist of an ensemble of hexagonal columns and 20-element aggregates with specific habit fractions at each particle size bin. The microphysical and optical properties of this two-habit model (THM) are compared with both laboratory and in situ measurements, and its performance in downstream satellite remote sensing applications is assessed. The ice water contents and median mass diameters calculated based on the THM closely agree with in situ measurements made during 11 field campaigns. In this study, the scattering, absorption, and polarization properties of ice crystals are calculated with a combination of the invariant imbedding T matrix, pseudo-spectral time domain, and improved geometric-optics methods over an entire practical range of particle sizes. The phase functions, calculated based on the THM, show close agreement with counterparts from laboratory and in situ measurements and from satellite-based retrievals. When the THM is applied to the retrievals of cloud microphysical and optical properties from MODIS (the Moderate Resolution Imaging Spectroradiometer) observations, excellent spectral consistency is achieved; specifically, the retrieved cloud optical thicknesses based on the visible/near infrared bands and the thermal infrared bands agree quite well. Furthermore, a comparison between the polarized reflectivities observed by the PARASOL satellite and from theoretical simulations illustrates that the THM can be used to represent ice cloud polarization properties.

One of the most serious tuber quality concerns of US chip potato growers is stem-end chip defect, which is defined as a localized post-fry discoloration in and adjacent to the vasculature on the stem end portion of potato chips. The severity and incidence of stem-end chip defect vary with growing location and variety, but quantitative data describing this are not available. A multi-year and location study was conducted to evaluate chipping potato varieties for tolerance to stem-end chip defect formation and to quantify defect severity and incidence regionally and temporally. It was observed that higher night temperature in July and August compared to the regional 30-year history was consistently associated with higher SECD severity. Average SECD severity was linearly correlated with incidence of chips having severe SECD. Chip color and tuber stem-end glucose content were significantly correlated with average SECD score across all treatments. Multiple tuber samplings from early growing season to mid post-harvest storage demonstrated that some varieties, such as Nicolet and Pike, had fewer stem-end chip defects than other varieties across years and locations. Stem-end chip defect was rarely observed prior to harvest, but was apparent at the time of harvest on multiple varieties depending on the year and location. Tuber stem-end sucrose and glucose prior to harvest were not indicators of defect development at harvest and out of storage, but pre-harvest chip color was significantly correlated with defect severity 10 weeks after preconditioning was finished.

Ice cloud bulk scattering models are derived for 445 discrete wavelengths between 0.2 µm and 100 µm. The methodology for deriving these optical models is based on microphysical data from 11 field campaigns using a variety of in situ probes, and incorporates a correction to mitigate the impact of ice particles that shatter at the probe inlets. The models are also based on a new library of ice habit single scattering properties developed for plates, droxtals, hollow and solid columns, hollow and solid bullet rosettes, an aggregate of solid columns, and a small/large aggregate of plates. Three sets of models are developed that assume the use of solid columns only, the aggregate of solid columns only, and a general habit mixture that incorporates all the habits. The consistency of the resulting models is explored. While the general habit mixture provides consistency with in situ microphysical measurements and the closest agreement with polarized reflectivities observed by the POLDER instrument on the PARASOL satellite, the aggregate of severely roughened solid columns provides the closest agreement between solar and infrared optical thicknesses. Finally, spectral results are presented for the shortwave and longwave models.

The 2006 Kiholo Bay, Hawaii, earthquake triggered high concentrations of rock falls and slides in the steep canyons of the Kohala Mountains along the north coast of Hawaii. Within these mountains and canyons a complex distribution of landslides was triggered by the earthquake shaking. In parts of the area, landslides were preferentially located on east‐facing slopes, whereas in other parts of the canyons no systematic pattern prevailed with respect to slope aspect or vertical position on the slopes. The geology within the canyons is homogeneous, so we hypothesize that the variable landslide distribution is the result of localized variation in ground shaking; therefore, we used a state‐of‐the‐art, high‐resolution ground‐motion simulation model to see if it could reproduce the landslide‐distribution patterns. We used a 3D finite‐element analysis to model earthquake shaking using a 10 m digital elevation model and slip on a finite‐fault model constructed from teleseismic records of the mainshock. Ground velocity time histories were calculated up to a frequency of 5 Hz. Dynamic shear strain also was calculated and compared with the landslide distribution. Results were mixed for the velocity simulations, with some areas showing correlation of landslide locations with peak modeled ground motions but many other areas showing no such correlation. Results were much improved for the comparison with dynamic shear strain. This suggests that (1) rock falls and slides are possibly triggered by higher frequency ground motions (velocities) than those in our simulations, (2) the ground‐motion velocity model needs more refinement, or (3) dynamic shear strain may be a more fundamental measurement of the decoupling process of slope materials during seismic shaking.

An environmental and technical sustainability assessment methodology is developed for both centralized and dual water distribution systems (WDSs) with and without fire flow scenarios. Technical sustainability of potable and reclaimed water networks is measured by a sustainability index (SI) assessment using reliability, resiliency, and vulnerability performance criteria. The U.S. Environmental Protection Agency EPANET software is used to simulate hydraulic (i.e. nodal pressure) and water quality (i.e. water age) analysis in a WDS. Total fresh water use and total energy intensity are considered as environmental sustainability criteria. The procedure considers two separate alternatives for meeting fire flows: (1) adding pumping to a system or (2) adding a non-potable WDS. The reclaimed system is designed using linear programming (LP) optimization. For each alternative, multi-criteria decision analysis (MCDA) is used to combine technical and environmental sustainability criteria for an urban WDS.

The influence of 3,5-diamino-1,2,4-triazole (DAT) on the electrochemical reduction of carbon dioxide to carbon monoxide on a silver electrode was studied via in situ surface-enhanced Raman spectroscopy (SERS). SERS bands obtained in the absence of DAT indicate potential-dependent adsorption of the CO product to bridge and 3-fold hollow sites. With the addition of DAT, CO adsorption to less-coordinated surface sites was found, including a physisorbed or noncoordinating site that exhibited no significant Stark vibrational shift. Raman peaks associated with adsorbed DAT observed at the same potentials as this species suggest that the ligand promotes weaker CO adsorption, which may be responsible for the high efficiency of the AgDAT catalyst. The observation of potential-dependent methylene stretching vibrations indicates the presence of surface hydrocarbon species while the presence of C–D stretches in deuterated electrolyte confirm that these hydrocarbons are generated as a CO2 reduction byproduct.

A methodology is presented for determining sustainability indices for pressure and water age in water distribution systems (WDSs). These sustainability indices are based upon performance criteria including reliability, resiliency, and vulnerability. Pressure and water age are determined for a WDS as a function of operation time using the U.S. Environmental Protection Agency EPANET model. The values of pressure and water age are used to determine reliability, resiliency, and vulnerability performance criteria, which are then combined into the nodal sustainability indices for water age and pressure. In addition, the sustainability index (SI) computations are performed for zones to define the SI for water age and SI for pressure. A combined SI calculation is performed to produce an overall sustainability score for the entire zone in the water distribution network. The proposed methodology can be used to monitor the sustainability of existing WDSs and to help define alternative solutions including changes in pump operation and modifications to WDS to increase the sustainability.

We consider here wind speed time series and the aggregate output wind power from a wind farm. We study their scaling statistics in the framework of fully developed turbulence and Kolmogorov's theory. We estimate their Fourier power spectra and consider their scaling properties in the physical space. We show that the atmospheric wind speed and the aggregate power output from a wind farm are intermittent and multifractal over a wide range of scales. The coupling between simultaneous data of the wind speed and aggregate power output is investigated through a joint multifractal description using the generalized correlation functions (GCFs). This multiscaling test is compatible with a linear relation between the wind speed and the aggregate power output fluctuations for timescales T &geqslant; 103 s &simeq; 15 min.

In the marine environment, many fields have fluctuations over a large range of different spatial and temporal scales. These quantities can be nonlinear \red{and} non-stationary, and often interact with each other. A good method to study the multiple scale dynamics of such time series, and their correlations, is needed. In this paper an application of an empirical mode decomposition based time dependent intrinsic correlation, \red{of} two coastal oceanic time series, temperature and dissolved oxygen (saturation percentage) is presented. The two time series are recorded every 20 minutes \red{for} 7 years, from 2004 to 2011. The application of the Empirical Mode Decomposition on such time series is illustrated, and the power spectra of the time series are estimated using the Hilbert transform (Hilbert spectral analysis). Power-law regimes are found with slopes of 1.33 for dissolved oxygen and 1.68 for temperature at high frequencies (between 1.2 and 12 hours) \red{with} both close to 1.9 for lower frequencies (time scales from 2 to 100 days). Moreover, the time evolution and scale dependence of cross correlations between both series are considered. The trends are perfectly anti-correlated. The modes of mean year 3 and 1 year have also negative correlation, whereas higher frequency modes have a much smaller correlation. The estimation of time-dependent intrinsic correlations helps to show patterns of correlations at different scales, for different modes., 35 pages with 22 figures

An ice microphysics parameterization scheme has been modified to better describe and understand ice fog formation. The modeling effort is based on observations in the Sub-Arctic Region of Interior Alaska, where ice fog occurs frequently during the cold season due to abundant water vapor sources and strong inversions existing near the surface at extremely low air temperatures. The microphysical characteristics of ice fog are different from those of other ice clouds, implying that the microphysical processes of ice should be changed in order to generate ice fog particles. Ice fog microphysical characteristics were derived with the NCAR Video Ice Particle Sampler during strong ice fog cases in the vicinity of Fairbanks, Alaska, in January and February 2012. To improve the prediction of ice fog in the Weather Research and Forecasting model, observational data were used to change particle size distribution properties and gravitational settling rates, as well as to implement a homogeneous freezing process. The newly implemented homogeneous freezing process compliments the existing heterogeneous freezing scheme and generates a higher number concentration of ice crystals than the original Thompson scheme. The size distribution of ice crystals is changed into a Gamma distribution with the shape factor of 2.0, using the observed size distribution. Furthermore, gravitational settling rates are reduced for the ice crystals since the crystals in ice fog do not precipitate in a similar manner when compared to the ice crystals of cirrus clouds. The slow terminal velocity plays a role in increasing the time scale for the ice crystals to settle to the surface. Sensitivity tests contribute to understanding the effects of water vapor emissions as an anthropogenic source on the formation of ice fog.

International audience; A good knowledge of the intermittency of global solar radiation is crucial for selecting the location of a solar power plant and predicting the generation of electricity. This paper presents a multifractal analysis study of 367 daily global solar radiation sequences measured with a sampling rate of 1 Hz over one year at Guadeloupean Archipelago (French West Indies) located at 16 150N latitude and 60 300W longitude. The mean power spectrum computed follows a power law behavior close to the Kolmogorov spectrum. The intermittent and multifractal properties of global solar radiation data are investigated using several methods. Under this basis, a characterization for each day using three multifractal parameters is proposed.