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See detailTwo Small Temperate Planets Transiting Nearby M Dwarfs in K2 Campaigns 0 and 1
Schlieder, Joshua E.; Crossfield, Ian J. M.; Petigura, Erik A. et al

in Astrophysical Journal (2016), 818

The prime Kepler mission revealed that small planets (<4 {R}[SUB]\oplus [/SUB]) are common, especially around low-mass M dwarfs. K2, the repurposed Kepler mission, continues this exploration of small ... [more ▼]

The prime Kepler mission revealed that small planets (<4 {R}[SUB]\oplus [/SUB]) are common, especially around low-mass M dwarfs. K2, the repurposed Kepler mission, continues this exploration of small planets around small stars. Here we combine K2 photometry with spectroscopy, adaptive optics imaging, and archival survey images to analyze two small planets orbiting the nearby field-age M dwarfs, K2-26 (EPIC 202083828) and K2-9. K2-26 is an {{M}}1.0+/- 0.5 dwarf at 93 ± 7 pc from K2 Campaign 0. We validate its planet with a day period of 14.5665 and estimate a radius of {2.67}[SUB]-0.42[/SUB][SUP]+0.46[/SUP] {R}[SUB]\oplus [/SUB]. K2-9 is an {{M}}2.5+/- 0.5 dwarf at 110 ± 12 pc from K2 Campaign 1. K2-9b was first identified by Montet et al.; here we present spectra and adaptive optics imaging of the host star and independently validate and characterize the planet. Our analyses indicate K2-9b is a {2.25}[SUB]-0.96[/SUB][SUP]+0.53[/SUP] {R}[SUB]\oplus [/SUB] planet with a 18.4498 day period. K2-26b exhibits a transit duration that is too long to be consistent with a circular orbit given its measured stellar radius. Thus, the long transits are likely due to the photoeccentric effect and our transit fits hint at an eccentric orbit. Both planets receive low incident flux from their host stars and have estimated equilibrium temperatures <500 K. K2-9b may receive approximately Earth-like insolation. However, its host star exhibits strong GALEX UV emission which could affect any atmosphere it harbors. K2-26b and K2-9b are representatives of a poorly studied class of small planets with cool temperatures that have radii intermediate to Earth and Neptune. Future study of these systems can provide key insight into trends in bulk composition and atmospheric properties at the transition from silicate dominated to volatile rich bodies. Based on observations collected at the European Organization for Astronomical Research in the Southern Hemisphere, La Silla Observatory, Chile during program ID 194.C-0443. [less ▲]

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See detailThe Inner Debris Structure in the Fomalhaut Planetary System
Su, Kate Y. L.; Rieke, George H.; Defrere, Denis ULg et al

in Astrophysical Journal (2016), 818

Fomalhaut plays an important role in the study of debris disks and small bodies in other planetary systems. The proximity and luminosity of the star make key features of its debris, like the water ice ... [more ▼]

Fomalhaut plays an important role in the study of debris disks and small bodies in other planetary systems. The proximity and luminosity of the star make key features of its debris, like the water ice line, accessible. Here we present ALMA cycle 1, 870 μm (345 GHz) observations targeted at the inner part of the Fomalhaut system with a synthesized beam of 0.″45 × 0.″37 (˜3 AU linear resolution at the distance of Fomalhaut) and an rms of 26 μJy beam[SUP]-1[/SUP]. The high angular resolution and sensitivity of the ALMA data enable us to place strong constraints on the nature of the warm excess revealed by Spitzer and Herschel observations. We detect a point source at the star position with a total flux consistent with thermal emission from the stellar photosphere. No structures that are brighter than 3σ are detected in the central 15 AU × 15 AU region. Modeling the spectral energy distribution using parameters expected for a dust-producing planetesimal belt indicates a radial location in the range of ˜8-15 AU. This is consistent with the location where ice sublimates in Fomalhaut, i.e., an asteroid-belt analog. The 3σ upper limit for such a belt is <1.3 mJy at 870 μm. We also interpret the 2 and 8-13 μm interferometric measurements to reveal the structure in the inner 10 AU region as dust naturally connected to this proposed asteroid belt by Poynting-Robertson drag, dust sublimation, and magnetically trapped nanograins. Fomalhaut is a triple system; here we refer to the Fomalhaut planetary system as the one around the primary star Fomalhaut A. [less ▲]

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See detailModels of the η Corvi Debris Disk from the Keck Interferometer, Spitzer, and Herschel
Lebreton, J.; Beichman, C.; Bryden, G. et al

in Astrophysical Journal (2016), 817

Debris disks are signposts of analogs to small-body populations of the solar system, often, however, with much higher masses and dust production rates. The disk associated with the nearby star η Crv is ... [more ▼]

Debris disks are signposts of analogs to small-body populations of the solar system, often, however, with much higher masses and dust production rates. The disk associated with the nearby star η Crv is especially striking, as it shows strong mid- and far-infrared excesses despite an age of ∼1.4 Gyr. We undertake constructing a consistent model of the system that can explain a diverse collection of spatial and spectral data. We analyze Keck Interferometer Nuller measurements and revisit Spitzer and additional spectrophotometric data, as well as resolved Herschel images, to determine the dust spatial distribution in the inner exozodi and in the outer belt. We model in detail the two-component disk and the dust properties from the sub-AU scale to the outermost regions by fitting simultaneously all measurements against a large parameter space. The properties of the cold belt are consistent with a collisional cascade in a reservoir of ice-free planetesimals at 133 AU. It shows marginal evidence for asymmetries along the major axis. KIN enables us to establish that the warm dust consists of a ring that peaks between 0.2 and 0.8 AU. To reconcile this location with the ∼400 K dust temperature, very high albedo dust must be invoked, and a distribution of forsterite grains starting from micron sizes satisfies this criterion, while providing an excellent fit to the spectrum. We discuss additional constraints from the LBTI and near-infrared spectra, and we present predictions of what James Webb Space Telescope can unveil about this unusual object and whether it can detect unseen planets. [less ▲]

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See detailThe LEECH Exoplanet Imaging Survey: Orbit and Component Masses of the Intermediate-age, Late-type Binary NO UMa
Schlieder, Joshua E.; Skemer, Andrew J.; Maire, Anne-Lise et al

in Astrophysical Journal (2016), 818

We present high-resolution Large Binocular Telescope LBTI/LMIRcam images of the spectroscopic and astrometric binary NO UMa obtained as part of the LBT Interferometer Exozodi Exoplanet Common Hunt ... [more ▼]

We present high-resolution Large Binocular Telescope LBTI/LMIRcam images of the spectroscopic and astrometric binary NO UMa obtained as part of the LBT Interferometer Exozodi Exoplanet Common Hunt exoplanet imaging survey. Our H-, K[SUB]s[/SUB]-, and L‧-band observations resolve the system at angular separations <0.″09. The components exhibit significant orbital motion over a span of ∼7 months. We combine our imaging data with archival images, published speckle interferometry measurements, and existing spectroscopic velocity data to solve the full orbital solution and estimate component masses. The masses of the K2.0 ± 0.5 primary and K6.5 ± 0.5 secondary are 0.83 ± 0.02 M[SUB]⊙[/SUB] and 0.64 ± 0.02 M[SUB]⊙[/SUB], respectively. We also derive a system distance of d = 25.87 ± 0.02 pc and revise the Galactic kinematics of NO UMa. Our revised Galactic kinematics confirm NO UMa as a nuclear member of the ∼500 Myr old Ursa Major moving group, and it is thus a mass and age benchmark. We compare the masses of the NO UMa binary components to those predicted by five sets of stellar evolution models at the age of the Ursa Major group. We find excellent agreement between our measured masses and model predictions with little systematic scatter between the models. NO UMa joins the short list of nearby, bright, late-type binaries having known ages and fully characterized orbits. Based on data obtained with the STELLA robotic telescope in Tenerife, an AIP facility jointly operated by AIP and IAC. [less ▲]

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See detailThe LEECH Exoplanet Imaging Survey: Characterization of the Coldest Directly Imaged Exoplanet, GJ 504 b, and Evidence for Superstellar Metallicity
Skemer, Andrew J.; Morley, Caroline V.; Zimmerman, Neil T. et al

in Astrophysical Journal (2016), 817

As gas giant planets and brown dwarfs radiate away the residual heat from their formation, they cool through a spectral type transition from L to T, which encompasses the dissipation of cloud opacity and ... [more ▼]

As gas giant planets and brown dwarfs radiate away the residual heat from their formation, they cool through a spectral type transition from L to T, which encompasses the dissipation of cloud opacity and the appearance of strong methane absorption. While there are hundreds of known T-type brown dwarfs, the first generation of directly imaged exoplanets were all L type. Recently, Kuzuhara et al. announced the discovery of GJ 504 b, the first T dwarf exoplanet. GJ 504 b provides a unique opportunity to study the atmosphere of a new type of exoplanet with a ˜500 K temperature that bridges the gap between the first directly imaged planets (˜1000 K) and our own solar system's Jupiter (˜130 K). We observed GJ 504 b in three narrow L-band filters (3.71, 3.88, and 4.00 μm), spanning the red end of the broad methane fundamental absorption feature (3.3 μm) as part of the LBTI Exozodi Exoplanet Common Hunt (LEECH) exoplanet imaging survey. By comparing our new photometry and literature photometry with a grid of custom model atmospheres, we were able to fit GJ 504 b's unusual spectral energy distribution for the first time. We find that GJ 504 b is well fit by models with the following parameters: T[SUB]eff[/SUB] = 544 ± 10 K, g < 600 m s[SUP]-2[/SUP], [M/H] = 0.60 ± 0.12, cloud opacity parameter of f[SUB]sed[/SUB] = 2-5, R = 0.96 ± 0.07 R[SUB]Jup[/SUB], and log(L) = -6.13 ± 0.03 L[SUB]⊙[/SUB], implying a hot start mass of 3-30 M[SUB]jup[/SUB] for a conservative age range of 0.1-6.5 Gyr. Of particular interest, our model fits suggest that GJ 504 b has a superstellar metallicity. Since planet formation can create objects with nonstellar metallicities, while binary star formation cannot, this result suggests that GJ 504 b formed like a planet, not like a binary companion. The LBT is an international collaboration among institutions in the United States, Italy, and Germany. LBT Corporation partners are the University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrophisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University, and the Research Corporation, on behalf of the University of Notre Dame, University of Minnesota, and University of Virginia. [less ▲]

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See detailExperimental and Numerical Characterization of Damage and Application to Incremental Forming
Guzmán Inostroza, Carlos Felipe ULg

Doctoral thesis (2016)

Nowadays, product manufacturing can be divided into two groups: relatively simple products produced in a large production chain and complex (specialized) components produced in reduced batches. Within the ... [more ▼]

Nowadays, product manufacturing can be divided into two groups: relatively simple products produced in a large production chain and complex (specialized) components produced in reduced batches. Within the second group, prototyping through incremental sheet forming (ISF) has been subject of several studies. ISF refers to processes where the plastic deformation occurs by repeated contact with a relatively small tool. A crucial aspect in the ISF processes is that the final shape is determined only by the tool movement. The focus of this research is the single point incremental forming (SPIF) process variant, where a clamped sheet metal is deformed by using a relatively small spherical tool. SPIF has several advantages over traditional forming, such as the high formability attainable by the material. Different hypothesis haven been proposed to explain this behavior, but there is still not a clear and definitive understanding of the relation between the particular stress and strain state induced in the material during SPIF and the material degradation leading to localization or fracture. In this thesis, a fundamental research is proposed using the finite element (FE) code LAGAMINE, developed within the University of Liège. Numerical implementation and validation of the Gurson-Tvergaard-Needleman (GTN) damage model into this FE code is performed. An experimental test campaign is developed to characterize plastic and damage behavior and to validate the damage model for the DC01 steel grade. Finally, this damage model is applied to simulate the SPIF process in order to verify if it is capable to predict failure. The thesis discusses the material parameter identification for classical plasticity models, describing the anisotropy and hardening behavior of the sheet metal. The derivation of the equations of the numerical damage model and the efficiency of the implementation is presented in great detail. A methodology for the numerical parameter identification of the damage model is proposed, including microscopic measurements by optical microscopy and strain and displacement field measurements by digital image correlation (DIC). The identified Gurson model is applied to simulate standard SPIF geometries, like the line, cone and pyramid tests. The simulations are performed using the solid-shell element formulation and validated in terms of shape and force prediction. Literature reviews of the Gurson model and the SPIF process are also included. The experimental results show that the selected material (DC01 steel sheet) exhibits a slight anisotropic behavior and work-hardening stagnation on cyclic tests. The performed microscopic measurements are not representative of the actual damage, but they give a qualitative estimation of the physical mechanism of fracture. The initial porosity of the material was determined using optical microscopy measurements in the base material. The numerical implementation of the model is developed with all variables integrated in an implicit way, based on the backward Euler scheme. Nucleation, coalescence and shear extensions implementations are validated by results obtained from the literature. The macroscopic campaign allowed to identify the parameters for nucleation, coalescence and shear. An unique set of results matching all experiments was not possible to obtain, so different sets of parameters are retrieved following an approach that includes inverse modeling and sensitivity analysis. A numerical-experimental comparison of strain values in the loading direction shows that the model is able to correctly predict the strain distribution except during localization of the strain. Globally, the obtained set of material parameters is in good agreement with the experimental results. For SPIF FE simulations, the results of the shape prediction are in good agreement with the experimental results, both for the line and pyramid test. Nevertheless, the force prediction is too high compared to reference values. On the other hand, the GTN model is capable to detect failure in a pyramid and a cone, but the prediction is too premature compared to the experimental failure angle for the same material and geometry. An accurate prediction of failure for the SPIF process was not possible to achieve. The GTN model extended to shear presents inherent flaws that prevent an accurate prediction of the failure angle for the SPIF process. Hence, an extensive research on the damage mechanisms leading to fracture for SPIF cannot rely (only) on the GTN model. The classical coalescence model of the GTN model is insufficient to correctly predict failure. Hence, it is recommended that further analysis concentrates on the description of this particular stage of damage evolution. During the development of this thesis, a robust implementation of the GTN model into the FE code LAGAMINE was done, including an extensive experimental database of microscopic and macroscopic measurements for the DC01 steel sheet. Other phenomena can be explored thanks to this model. [less ▲]

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See detailVolatile organic compounds discriminate between eosinophilic and neutrophilic inflammation in vitro.
SCHLEICH, FLorence ULg; Dallinga, Jan W.; HENKET, Monique ULg et al

in Journal of breath research (2016), 10(1), 016006

Inflammation associated oxidative stress leads to peroxidation of polyunsaturated fatty acids thereby generating volatile organic compounds (VOCs). The integrative analysis of the total amount of VOCs ... [more ▼]

Inflammation associated oxidative stress leads to peroxidation of polyunsaturated fatty acids thereby generating volatile organic compounds (VOCs). The integrative analysis of the total amount of VOCs released by eosinophils and neutrophils in vitro enables the search for those compounds that discriminates between various inflammatory conditions. The approach comprises isolating eosinophils and neutrophils from 30 ml of blood of healthy non-smoking volunteers by gradient centrifugation, using lymphoprep. Eosinophils are separated from neutrophils by immunomagnetic cell separation using anti-CD16. Cells are activated with phorbol 12-myristate 13-acetate and VOCs from the headspace are collected at time 0', 30', 60' and 90' by introduction of ultra-pure nitrogen in the closed flasks at a flow rate of 200 ml min(-1) during 10 min. The gases are trapped onto a sorption tube and analyzed by gas chromatography-time-of-flight-mass spectometry (GC-TOF-MS) in order to identify VOCs released in the headspace by activated neutrophils and eosinophils. Eosinophils and neutrophils were isolated from 26 healthy non-smoking volunteers. The average absolute number of eosinophils and neutrophils upon isolation was 3.5 x 10(6) and 19.4 x 10(6), respectively. The volatome in headspace consisted of 2116 compounds and those compounds present in at least 8% of the samples (1123 compounds) were used for further discriminant analysis. Discriminant analysis showed that two VOCs were able to distinguish between eosinophilic and neutrophilic cultures in the unactivated state with 100% correct classification of the entire data set and upon cross validation while five VOCs were able to discriminate between activated eosinophils and neutrophils with 96% correct classification in the original set and upon cross-validation. Analysis of VOCs seems to be a very promising approach in identifying eosinophilic and neutrophilic inflammation but it needs further development and in vivo confirmation. [less ▲]

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See detailResidual tumor micro-foci and overwhelming regulatory T lymphocyte infiltration are the causes of bladder cancer recurrence.
Parodi, Alessia; Traverso, Paolo; Kalli, Francesca et al

in Oncotarget (2016), 7(6), 6424-6435

Bladder cancer has an unexplained, high recurrence rate. Causes of recurrence might include the presence of sporadic tumor micro-foci in the residual urothelial tissue after surgery associated with an ... [more ▼]

Bladder cancer has an unexplained, high recurrence rate. Causes of recurrence might include the presence of sporadic tumor micro-foci in the residual urothelial tissue after surgery associated with an inverted ratio between intratumoral effector and regulatory T cell subsets. Hence, surgical specimens of both tumors and autologous, macroscopically/histologically free-of-tumor tissues were collected from 28 and 20 patients affected by bladder or renal cancer, respectively. The frequencies of effector (IFNγ+ and IL17+ T cells) and regulatory (CD4+CD25hiCD127lo and CD8+CD28-CD127loCD39+ Treg) T cell subpopulations among tumor infiltrating lymphocytes were analyzed by immunofluorescence, while the gene expression of MAGE-A1 and MAGE-A2 tumor-associated antigens was studied by RT-PCR. The results show that both the T cell infiltrate and the frequency of MAGE-A1/A2 gene expression were comparable in tumors and in autologous free-of-tumor tissues in bladder cancer, while the autologous free-of-tumor renal tissues showed reduced T cell infiltrate and frequency of MAGE gene expression as compared to the autologous tumors. Importantly, the intra-tumor T effector/Treg cell ratio was consistently <1 in bladder cancer patients (n. 7) who relapsed within two years, while it was always >1 in patients (n. 6) without recurrence (regardless of tumor stage) (P = 0.0006, Odds ratio = 195). These unprecedented findings clarify the pathogenic mechanism of bladder cancer recurrence and suggest that microscopically undetectable micro-foci of tumor may predispose to recurrence when associated with an inverted intratumoral T effector/Treg cell ratio. [less ▲]

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See detailSubstituted azafluorenones: access from dihalogeno diaryl ketones by palladium-catalyzed auto-tandem processes and evaluation of their antibacterial, antifungal, antimalarial and antiproliferative activities
Marquise, Nada; Chevallier, Floris; Nassar, Ekhlas et al

in Tetrahedron (2016), 72(6), 825-836

Substituted azafluorenones were synthesized from dihalogeno diaryl ketones under palladium catalysis by combining, in auto-tandem processes, Suzuki coupling and intramolecular arylation reactions ... [more ▼]

Substituted azafluorenones were synthesized from dihalogeno diaryl ketones under palladium catalysis by combining, in auto-tandem processes, Suzuki coupling and intramolecular arylation reactions. Different dihalogenated diaryl ketones, prepared by sequential deprotocupration-aroylation, were identified as suitable substrates to this purpose. Conditions were identified to allow successful syntheses of several 6-/7-arylated 4-azafluorenones, 1-substituted 4-azafluorenones, 2-phenyl-3-azafluorenone, and 4-phenyl-3-azafluorenone from 3-(bromobenzoyl)-2-chloropyridines, 3-benzoyl-4-bromo-2-chloropyridines, 4-benzoyl-2,5-dichloropyridine, and 4-benzoyl-2,3-dichloropyridine, respectively. Some of the synthesized compounds exhibit interesting biological properties [less ▲]

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See detailComputed Tomography and Magnetic Resonance Findings in Athletes at Risk for Sudden Cardiac Death
Ghekiere, Olivier; Nchimi Longang, Alain ULg; Bijnens, Eric et al

in Journal of the Belgian Society of Radiology (2016, February), 1

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See detailNumerical modeling of the long term behavior of Municipal Solid Waste in a bioreactor landfill
Hubert, Julien ULg; Xianfeng, Liu; Collin, Frédéric ULg

in Computers and Geotechnics (2016), 72

This paper presents a thermo-hydro–biochemo-mechanical model for simulating the long term behavior of Municipal Solid Waste (MSW) in a bioreactor landfill, in which the multi-physics coupling mechanism ... [more ▼]

This paper presents a thermo-hydro–biochemo-mechanical model for simulating the long term behavior of Municipal Solid Waste (MSW) in a bioreactor landfill, in which the multi-physics coupling mechanism plays a dominant role. In the model, a two-stage anaerobic biochemical model based on McDougall’s formulation is incorporated into a fully coupled thermo-hydro-mechanical models originally developed for unsaturated porous medium. The mechanical model is a modified Camclay model allowing for biochemical hardening/softening, while the thermal model is described by a classical energy balance equation with a source term accounting for the heat generation from the biodegradation of organic matter. The hydraulic model is an unsaturated flow model using Richard’s equation. The derived coupled model is implemented into an in-house built multi-physics finite element code. Finally, numerical simulations were performed to illustrate the capability of the proposed model for estimating long-term settlement of a bioreactor landfill and its aptitude as a landfill management tool for optimizing the landfill operation [less ▲]

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See detailTransformational Leadership, Role Conflict and the Moderating Role of Uncertainty Avoidance
Selzer, Veronika Luisa; Schumann, Jan Hendrik; Büttgen, Marion et al

Conference (2016, February)

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See detailLa diversité des expressions culturelles au tourbillon du numérique
Vlassis, Antonios ULg

E-print/Working paper (2016)

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See detailGeschichtsvereine und Geschichtsbewusstsein in der DG (2. Teil)
Brüll, Christoph ULg

Article for general public (2016)

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See detailUse of dual carbon-chlorine isotope analysis to assess the degradation pathways of 1,1,1-trichloroethane in groundwater
Palau, Jordi; Jamin, Pierre ULg; Badin, Alice et al

in Water Research (2016)

Compound-specific isotope analysis (CSIA) is a powerful tool to track contaminant fate in groundwater. However, the application of CSIA to chlorinated ethanes has received little attention so far. These ... [more ▼]

Compound-specific isotope analysis (CSIA) is a powerful tool to track contaminant fate in groundwater. However, the application of CSIA to chlorinated ethanes has received little attention so far. These compounds are toxic and prevalent groundwater contaminants of environmental concern. The high susceptibility of chlorinated ethanes like 1,1,1-trichloroethane (1,1,1-TCA) to be transformed via different competing pathways (biotic and abiotic) complicates the assessment of their fate in the subsurface. In this study, the use of a dual C-Cl isotope approach to identify the active degradation pathways of 1,1,1-TCA is evaluated for the first time in an aerobic aquifer impacted by 1,1,1-TCA and trichloroethylene (TCE) with concentrations of up to 20 mg/L and 3.4 mg/L, respectively. The reaction-specific dual carbon-chlorine (C-Cl) isotope trends determined in a recent laboratory study illustrated the potential of a dual isotope approach to identify contaminant degradation pathways of 1,1,1-TCA. Compared to the dual isotope slopes (Δδ13C/Δδ37Cl) previously determined in the laboratory for dehydrohalogenation / hydrolysis (DH/HY, 0.33 ± 0.04) and oxidation by persulfate (∞), the slope determined from field samples (0.6 ± 0.2, r2 = 0.75) is closer to the one observed for DH/HY, pointing to DH/HY as the predominant degradation pathway of 1,1,1-TCA in the aquifer. The observed deviation could be explained by a minor contribution of additional degradation processes. This result, along with the little degradation of TCE determined from isotope measurements, confirmed that 1,1,1-TCA is the main source of the 1,1-dichlorethylene (1,1-DCE) detected in the aquifer with concentrations of up to 10 mg/L. This study demonstrates that a dual C-Cl isotope approach can strongly improve the qualitative and quantitative assessment of 1,1,1-TCA degradation processes in the field. [less ▲]

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See detailNew perspectives for the design of sustainable bioprocesses for phosphorus recovery from waste
Tarayre, Cédric ULg; De Clercq, Lies; Charlier, Raphaëlle et al

in Bioresource Technology (2016), 206

Phosphate rock has long been used for the production of phosphorus based chemicals. However, considering the depletion of the reservoirs and the decrease of the quality of phosphate rocks, a potential ... [more ▼]

Phosphate rock has long been used for the production of phosphorus based chemicals. However, considering the depletion of the reservoirs and the decrease of the quality of phosphate rocks, a potential market is now emerging for the recovery of phosphate from waste and its reuse for different applications. Notably, phosphate recovery from wastewater could be included in a circular economy approach. This review focuses on the use of microbial systems for phosphorus accumulation and recovery, by considering the actual range of analytical techniques available for the monitoring of phosphorus accumulating organisms, as well as the actual biochemical and metabolic engineering toolbox available for the optimization of bioprocesses. In this context, knowledge gathered from process, system and synthetic biology could potentially lead to innovative process design. [less ▲]

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See detailDoes biobased polymer achieve better environmental impacts than fossil polymer? Comparison of fossil HDPE and biobased HDPE produced from sugar beet and wheat
Belboom, Sandra ULg; Léonard, Angélique ULg

in Biomass & Bioenergy (2016), 85

Polymers are one of the most used materials and the majority of their production is based on fossil fuels. Due to the decrease of oil resources and concerns about climate change, alternatives are needed ... [more ▼]

Polymers are one of the most used materials and the majority of their production is based on fossil fuels. Due to the decrease of oil resources and concerns about climate change, alternatives are needed, the transformation of biobased ethanol into biobased polymer being one of them. This paper undertakes an environmental evaluation of the production of biobased polymer produced from two different feedstock cultivated in Belgium: sugar beet and wheat. Both crops cultivation are studied as well as their transformation into biobased ethanol, first, and then to biobased ethylene, focusing on high-density polyethylene (HDPE) as final product. These scenarios are analyzed and compared with the production of conventional polymer using the life-cycle assessment (LCA) methodology with reference to relevant environmental impact categories. This study shows a reduction of impact of around 60% for both climate change and fossil fuel depletion categories when using biobased HDPE instead of its fossil counterpart. For all other impact categories, fossil HDPE achieves better results than the biobased product. [less ▲]

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See detailLet’s work together
Chatelus, Renaud ULg; Sevini, Filippo

in WorldECR (2016), issue 47

Export control systems are complex by nature. They involve many national stakeholders. A typical national export controlapparatus requires the cooperation of between seven and 15 governmental ministries ... [more ▼]

Export control systems are complex by nature. They involve many national stakeholders. A typical national export controlapparatus requires the cooperation of between seven and 15 governmental ministries, services and agencies, each having its own mandate, constraints and work culture. But export control cannot be seen from a purely national perspective. Export control’s ultimate purpose, overall efficacy, and legal basis are genuinely international. International instruments and bodies, such as Resolution 1540 and its committee, or the various multilateral export control regimes, provide some guidance and opportunities for cooperation. It is, however, far from sufficient for addressing all the cooperation challenges at the national and international levels. Recognising this important need for cooperation, the Nuclear Security Unit of the European Joint Research Centre in Ispra, Italy, organised in March 2015, a three-day innovative EU export control simulation exercise with operatives of 11 Member States, involving standard work processes as well as specific fraud patterns. [less ▲]

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