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• Implemented K-CliqueWeight into the ProBiS-Dock algorithm, enhancing its capabilities for molecular docking. • Efficiently identifies the top N weighted k-cliques, addressing challenges in molecular docking and diverse problem domains. • Demonstrated superior performance of K-CliqueWeight, surpassing alternatives by several orders of magnitude. • Accessible to academia for free at http://insilab.org/kcliqueweight, facilitating widespread use. Molecular docking, a key process in drug discovery, is often used in the discovery of new bioactive compounds. In this technique, small molecules are systematically placed at a protein binding site to identify the ligands with the highest binding affinity. Here we have developed a new graph-theoretical algorithm called K-CliqueWeight. This algorithm efficiently identifies the top N highest weight k-cliques in different types of vertex-weighted graphs and can serve as a building block for various algorithms addressing different problems, including molecular docking. K-CliqueWeight and its variant K-CliqueDynWeight are extensions of our established and widely used maximum clique algorithm. Our new algorithm uses a novel approach to approximate graph coloring and provides efficient upper bounds on the size and weight of a k-clique within the branch-and-bound algorithm. It outperforms alternative methods and often shows a speedup of several orders of magnitude. Rigorous tests with general random graphs and those specifically designed for docking confirm its exceptional performance. K-CliqueWeight has been integrated into the existing ProBiS-Dock algorithm for molecular docking. The algorithm is freely available to the academic community at http://insilab.org/kcliqueweight. [Display omitted] [ABSTRACT FROM AUTHOR]

• Fast pyrolysis of mannan-rich ivory nut was performed at 350 °C and 500 °C. • Pyrolysis liquids (yield 58–60 wt%) were rich in levomannosan and 5-hydroxymethyl furfural. • Biochar and non-condensible gases (NCGs) were characterized. • Biochar holds potential for e.g. soil applications, NCGs hold potential for e.g. syngas processes. Ivory nut residues from the palm Phytelephas aequatorialis were converted via fast pyrolysis into a set of valuable biorefinery products, being (i) pyrolysis liquids rich in levomannosan and 5-hydroxymethyl furfural (5-HMF), (ii) biochar, with potential for soil applications, (iii) and non-condensable gases with potential for upgrading and syngas processes. The ivory nut residues were mannan-rich leftovers from button manufacturing in Ecuador. A handful of studies, dating back from the 20th century, have investigated gram-scale valorization of ivory nut to e.g. mannose. Nevertheless, advances in science and technology on biorefinery products called for a comprehensive reassessment of the valorization potential of this underutilized feedstock. A fully equipped, continuously operated lab-scale reactor (200 g.h−1 feed) was used for pyrolysis at 350 °C and 500 °C. The pyrolysis liquid yield was 57.53 wt% at 350 °C and 60.36 wt% at 500 °C. The aqueous phase obtained at 350 °C contained 17.5 wt% (d.b.) anhydrosugars, of which 90% was levomannosan, and contained 11.6 wt% (d.b.) furans, of which 56% was 5-HMF and 17% furfural. The carbon stability of the biochars, measured with the Edinburgh accelerated ageing tool, were 40.6% and 64.6%, respectively. Non-condensable gases during pyrolysis at 350 °C only were composed of CO 2 and CO (CO 2 :CO molar ratio of 4:1), while at 500 °C, gases were obtained with a CO 2 :CO:H 2 :CH 4 molar ratio of 9:9:4:1. Overall, the results demonstrate that pyrolysis of ivory nut holds potential as starting point for valuable biorefinery products. [ABSTRACT FROM AUTHOR]

Abstract Lignin-rich digested stillage as a novel feedstock for biochar production was subjected to slow pyrolysis. The lignin residue stemmed from a lignocellulosic ethanol pilot run with poplar, from which the stillage was anaerobically digested prior to pyrolysis. Pyrolysis conditions were optimized to meet guidelines put forth by the International Biochar Initiative and the European Biochar Certificate (molar H/C org ratio < 0.7 and O/C org ratio < 0.4), as biochar could be carbon-negative upon soil amendment, while reallocating nutrients to the field. Bench-scale pyrolysis of the lignin residue and straw were conducted according to a 33 factorial design with center runs (ranges: 370–450 °C highest treatment temperature, 5–45 min holding time and 5–50 °C.min−1 heating rate). Parametric and nonparametric statistics revealed that the highest treatment temperature was by far the most influencing factor for both feedstocks which 'pushed' H/C and O/C ratios within the desired range. Lignin-based biochar can be obtained with 50.7% yield, a H/C ratio of 0.70 and an O/C ratio of 0.20, already at 384 °C. This is considerably better when compared to straw-based biochar with identical H/C and O/C ratios, which came with a lower yield (33.7%) and required a modestly higher temperature (410 °C). Results from this study emphasize the feasibility to integrate slow pyrolysis in a lignocellulosic biorefinery. Graphical abstract Image 1 Highlights • Lignin residue from digested stillage was pyrolysed to biochar for the first time. • Temperature, heating rate and holding time were varied in a 33 factorial design. • Statistical models were used for process optimization to meet biochar standards. • The quality-quantity trade-off during pyrolysis was assessed. • At 384 °C, lignin-biochar with H/C = 0.7 and O/C = 0.2 is obtained with 50.71% yield. [ABSTRACT FROM AUTHOR]

A tubular furnace is combined with a diode laser spectrometer to record the high temperature near infrared absorption spectrum of methane at a pressure of 80 Torr. The investigated spectral range covers the 5693–6257 cm −1 (1.75–1.60 µm) range of the tetradecad dominated by the 2ν 3 band near 6000 cm −1 . Various determinations (thermocouples, Doppler line broadening, rotational temperature) provide a value of about 964 K for the gas temperature. Lines with intensity larger than 5 × 10 −24  cm/molecule at 1000 K are detected. As a result of the high temperature, high- J rovibrational transitions up to J  ≈ 20 and hot bands are identified in the spectrum. The recorded spectra provide tests of various methane line lists recently released in the literature: HITRAN2016, experimental list derived from emission spectra, the MeCaSDa empirical line list and the TheoReTs and ExoMol theoretical line lists. The agreement with the TheoReTs line list is found to be very good in the studied region. [ABSTRACT FROM AUTHOR]

The methane absorption spectrum is studied at 297 K and 80 K in the center of the Tetradecad between 5695 and 5850 cm −1 . The spectra are recorded by differential absorption spectroscopy (DAS) with a noise equivalent absorption of about α min   ≈ 1.5 × 10 −7 cm −1 . Two empirical line lists are constructed including about 4000 and 2300 lines at 297 K and 80 K, respectively. Lines due to 13 CH 4 present in natural abundance were identified by comparison with a spectrum of pure 13 CH 4 recorded in the same temperature conditions. About 1700 empirical values of the lower state energy level, E emp , were derived from the ratios of the line intensities at 80 K and 296 K. They provide accurate temperature dependence for most of the absorption in the region (93% and 82% at 80 K and 296 K, respectively). The quality of the derived empirical values is illustrated by the clear propensity of the corresponding lower state rotational quantum number, J emp , to be close to integer values. Using an effective Hamiltonian model derived from a previously published ab initio potential energy surface, about 2060 lines are rovibrationnally assigned, adding about 1660 new assignments to those provided in the HITRAN database for 12 CH 4 in the region. [ABSTRACT FROM AUTHOR]

An improved general understanding of riverbed heterogeneity is of importance for all groundwater modeling studies that include river-aquifer interaction processes. Riverbed hydraulic conductivity ( K ) is one of the main factors controlling river-aquifer exchange fluxes. However, the meter-scale spatial variability of riverbed K has not been adequately mapped as of yet. This study aims to fill this void by combining an extensive field measurement campaign focusing on both horizontal and vertical riverbed K with a detailed geostatistical analysis of the meter-scale spatial variability of riverbed K . In total, 220 slug tests and 45 standpipe tests were performed at two test sites along the Belgian Aa River. Omnidirectional and directional variograms (along and across the river) were calculated. Both horizontal and vertical riverbed K vary over several orders of magnitude and show significant meter-scale spatial variation. Horizontal K shows a bimodal distribution. Elongated zones of high horizontal K along the river course are observed at both sections, indicating a link between riverbed structures, depositional environment and flow regime. Vertical K is lognormally distributed and its spatial variability is mainly governed by the presence and thickness of a low permeable organic layer at the top of the riverbed. The absence of this layer in the center of the river leads to high vertical K and is related to scouring of the riverbed by high discharge events. Variograms of both horizontal and vertical K show a clear directional anisotropy with ranges along the river being twice as large as those across the river. [ABSTRACT FROM AUTHOR]

A microbial production process was developed to convert CO 2 and valeric acid into tailored poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) bioplastics. The aim was to understand microbial PHBV production in mixotrophic conditions and to control the monomer distribution in the polymer. Continuous sparging of CO 2 with pulse and pH-stat feeding of valeric acid were evaluated to produce PHBV copolyesters with predefined properties. The desired random monomer distribution was obtained by limiting the valeric acid concentration (below 1  g L - 1 ). 1 H-NMR, 13 C-NMR and chromatographic analysis of the PHBV copolymer confirmed both the monomer distribution and the 3-hydroxyvalerate (3HV) fraction in the produced PHBV. A physical-based model was developed for mixotrophic PHBV production, which was calibrated and validated with independent experimental datasets. To produce PHBV with a predefined 3HV fraction, an operating diagram was constructed. This tool was able to predict the 3HV fraction with a very good accuracy (2% deviation). [ABSTRACT FROM AUTHOR]

This paper analyses an experiment on the effect of an individualized, digital practice tool on numeracy skills for 337 seventh grade students. The first stage of the experiment shows that offering students the opportunity to practice numeracy digitally at home (intent-to-treat) leads to a substantial and significant increase in numeracy performance growth. The second stage reveals that the effectiveness of the tool mainly stems from its individualized nature. With good implementation prospects and relatively low costs, the consequences are discussed to be potentially large. [ABSTRACT FROM AUTHOR]

This work pioneers the thermocatalytic conversion of tagua seeds (or ivory nut) from the palm Phytelephas aequatorialis into key chemical building blocks, being levoglucosenone, furfural and levomannosan. Annually, ca. 100,000 metric ton of those seeds are produced in Ecuador. Mannan (a mannose-polymer similar to cellulose) is the main constituent in tagua. Thermocatalytic conversions were first explored on analytical scale to see if – and to which extent – e.g., levoglucosenone, was obtained from tagua, using catalysts with proven activity for cellulose conversion, being H3PO4 or ZnCl2. Non-catalytic fast pyrolysis led to levomannosan as main product (33.89 wt% ± 0.24 wt%), much like levoglucosan is the main product from cellulose pyrolysis. Catalytic fast pyrolysis using H3PO4 or ZnCl2 resulted in value-added levoglucosenone (max 6.64 wt% ± 0.27 wt%) and furfural (max 13.17 wt% ± 0.66 wt%) at the expense of levomannosan (between 12 wt.%–14 wt%). Validation experiments with a continuous fast pyrolysis auger reactor were successful and led to pyrolysis liquids with e.g., 3.69 wt% levoglucosenone, using H3PO4 -infused ivory nut. Although further optimization should follow this work, the results showcased a fundamental "mannan to levoglucosenone and furfural" conversion and therefore the potential of mannan-rich feedstock for biorefining. Moreover, these results can be translated to other mannan-rich agricultural residues, like açaí seeds, which are a major residue in Brazil (1.1 million metric ton annually). [Display omitted] • Mannan-rich tagua was demonstrated a valuable biorefinery feedstock. • Tagua was converted to levoglucosenone and furfural with H 3 PO 4 and ZnCl 2 , resp. • Analytical experiments were successfully translated to mini-plant scale experiments. • The biorefinery potential of mannan-rich ivory nut has been showcased. [ABSTRACT FROM AUTHOR]

Classical iterative methods for tomographic reconstruction include the class of Algebraic Reconstruction Techniques (ART). Convergence of these stationary linear iterative methods is however notably slow. In this paper we propose the use of Krylov solvers for tomographic linear inversion problems. These advanced iterative methods feature fast convergence at the expense of a higher computational cost per iteration, causing them to be generally uncompetitive without the inclusion of a suitable preconditioner. Combining elements from standard multigrid (MG) solvers and the theory of wavelets, a novel wavelet-based multi-level (WMG) preconditioner is introduced, which is shown to significantly speed-up Krylov convergence. The performance of the WMG-preconditioned Krylov method is analyzed through a spectral analysis, and the approach is compared to existing methods like the classical Simultaneous Iterative Reconstruction Technique (SIRT) and unpreconditioned Krylov methods on a 2D tomographic benchmark problem. Numerical experiments are promising, showing the method to be competitive with the classical Algebraic Reconstruction Techniques in terms of convergence speed and overall performance (CPU time) as well as precision of the reconstruction. [ABSTRACT FROM AUTHOR]

We have ported the numerical factorization and triangular solve phases of the sparse direct solver STRUMPACK to GPU. STRUMPACK implements sparse LU factorization using the multifrontal algorithm, which performs most of its operations in dense linear algebra operations on so-called frontal matrices of various sizes. Our GPU implementation off-loads these dense linear algebra operations, as well as the sparse scatter–gather operations between frontal matrices. For the larger frontal matrices, our GPU implementation relies on vendor libraries such as cuBLAS and cuSOLVER for NVIDIA GPUs and rocBLAS and rocSOLVER for AMD GPUs. For the smaller frontal matrices we developed custom CUDA and HIP kernels to reduce kernel launch overhead. Overall, high performance is achieved by identifying submatrix factorizations corresponding to sub-trees of the multifrontal assembly tree which fit entirely in GPU memory. The multi-GPU setting uses SLATE (Software for Linear Algebra Targeting Exascale) as a modern GPU-aware replacement for ScaLAPACK. On 4 nodes of SUMMIT the code runs ∼ 10 × faster when using all 24 V100 GPUs compared to when it only uses the 168 POWER9 cores. On 8 SUMMIT nodes, using 48 V100 GPUs, the sparse solver reaches over 50TFlop/s. Compared to SuperLU, on a single V100, for a set of 17 matrices our implementation is faster for all but one matrix, and is on average 5 × (median 4 ×) faster • Ported the numerical factorization and triangular solve phases of the sparse direct multifrontal solver STRUMPACK to GPU. • GPU off-loading of dense linear algebra operations, as well as the sparse scatter–gather operations between frontal matrices. • Relying on vendor libraries such as cuBLAS and cuSOLVER for Nvidia GPUs and rocBLAS and rocSOLVER for AMD GPUs. • Multi-GPU setting uses SLATE (Software for Linear Algebra Targeting Exascale) as a modern GPU-aware replacement for ScaLAPACK. • On 4 nodes of SUMMIT the code runs ∼ 10 × faster when using all 24 V100 GPUs compared to when it only uses the 168 POWER9 cores. On 8 SUMMIT nodes, using 48 V100 GPUs, the sparse solver reaches over 50TFlop/s. Compared to SuperLU, on a single V100, for a set of 17 matrices our implementation is faster for all but one matrix, and is on average 5x faster. [ABSTRACT FROM AUTHOR]

Highlights: [•] The manuscript presents a highly scalable preconditioned Conjugate Gradient method. [•] It presents a pipelined preconditioned Conjugate Residual method. [•] It shows how global communication can be overlapped with local work. [•] It shows numerical stability of the methods. [•] It shows improved scalability and runtime compared to CG and CR. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we have revisited the spectroscopy of the R(6) manifold of the ν3 band of methane which is particularly suitable for in situ laser monitoring of CH4. For that purpose, a home-made Difference Frequency Generation (DFG) laser emitting at 3.24µm has been coupled to a cryogenically-cooled optical cell to investigate the temperature dependences of the air-broadening, the air-narrowing and the air-mixing coefficients of these ν3 R(6) manifold transitions. The temperatures of the measurements range from 213.5K to room temperature. These are typically the temperatures found in the troposphere and the lower stratosphere. Finally, the measured spectroscopic parameters have been used to process the in-situ methane absorption spectra recorded by a balloon-borne laser diode spectrometer. [Copyright &y& Elsevier]

Abstract: PSII antenna size heterogeneity has been intensively studied in the past. Based on DCMU fluorescence rise kinetics, multiple types of photosystems with different properties were described. However, due to the complexity of fluorescence signal analysis, multiple questions remain unanswered. The number of different types of PSII is still debated as well as their degree of connectivity. In Chlamydomonas reinhardtii we found that PSIIα possesses a high degree of connectivity and an antenna 2–3 times larger than PSIIβ, as described previously. We also found some connectivity for PSIIβ in contrast with the majority of previous studies. This is in agreement with biochemical studies which describe PSII mega-, super- and core-complexes in Chlamydomonas. In these studies, the smallest unit of PSII in vivo would be a dimer of two core complexes hence allowing connectivity. We discuss the possible relationships between PSIIα and PSIIβ and the PSII mega-, super- and core-complexes. We also showed that strain and medium dependent variations in the half-time of the fluorescence rise can be explained by variations in the proportions of PSIIα and PSIIβ. When analyzing the state transition process in vivo, we found that this process induces an inter-conversion of PSIIα and PSIIβ. During a transition from state 2 to state 1, DCMU fluorescence rise kinetics are satisfactorily fitted by considering two PSII populations with constant kinetic parameters. We discuss our findings about PSII heterogeneity during state transitions in relation with recent results on the remodeling of the pigment-protein PSII architecture during this process. [Copyright &y& Elsevier]

• Acid leaching breaks down the chemical structure of carbohydrates and proteins. • Pretreatment effects on pyrolysis volatiles have been discussed. • Removal of inorganics increased the relative yields in aromatics and aliphatics. • Influence of water-soluble and acid-soluble AAEM species was discussed. • Interactions between microalgae components and AAEMs catalysis were elucidated. This study compared the volatiles distribution in analytical scale pyrolysis (py-GC–MS) of Nannochloropsis gaditana (marine microalgae) and Scenedesmus almeriensis (freshwater microalgae) and their demineralized counterparts. The role of inorganic elements and their removal via ultrasonic treatment, water washing and (in)organic acid leaching were elucidated. Principal component analysis (PCA) and grey relational analysis were applied to analyze the pyrolysis volatiles distribution and demonstrate the influence of inorganic elements in pyrolysis, respectively. Demineralization affects (breaks down) the chemical structure of carbohydrates, followed by (to a lesser extent) proteins and lipids. Acid leaching promoted hydrolysis and suppressed the catalytic effect associated to inorganic elements in subsequent pyrolysis, compared to ultrasonic treatment and water washing. Elements like K and Na had a larger catalytic influence on microalgae pyrolysis than Ca and Mg. The composition and pyrolytic formation mechanism of major product groups at 500 °C were studied, including anhydrosugars, phenolics, furans, carboxylic acids, alcohols, aliphatic hydrocarbons, aromatic hydrocarbons, N-heterocyclic compounds, nitriles and amides. The results indicate that demineralization shows positive effects on fast pyrolysis of microalgae: (1) by disrupting the cell wall and releasing the lipids and cellular contents. Based on the py-GC–MS peak area normalized to sample mass, the relative contribution of hydrocarbons in the pyrolysis vapors increased from 25.5 % (NG: Nannochloropsis gaditana) to 32.1 % (NG-HCl: Nannochloropsis gaditana, HCl treated), and from 16.1 % (SA: Scenedesmus almeriensis) to 22.4 % (SA-HCl: Scenedesmus almeriensis, HCl treated); (2) by decreasing the relative yields in O-containing compounds resulting from the suppressed catalytic effects of alkali and alkaline earth metals (53.3 % (NG) to 37.1 % (NG-HCl), 57.5 % (SA) to 47.8 % (SA-HCl)) that would otherwise have been present in non-demineralized microalgae feedstock. The effects of demineralization on the denitrogenation of pyrolysis vapors were not that obvious. Suggestions for potential full scale applications have been proposed. [ABSTRACT FROM AUTHOR]

The long-term stability of biochar in soil is key for carbon capture and storage and soil amelioration. Yet, its assessment is hampered by the long time-horizons needed to actually probe biochar's stability. Therefore, quick and reliable estimation methods are sought. Analytical pyrolysis (Py-GC-MS) offers a quick tool to predict biochar's stability in soil, if adequate and validated metrics can be extracted from it. This work derives and validates stability scores from biochar pyrograms and advanced data analysis. The stability scores were benchmarked by comparison with other stability metrics (Edinburgh stability tool, fixed carbon content and atomic H/C ratio). Calibration of the stability scores with these stability metrics had an R 2 between 0.61 and 0.95; validation resulted in R 2 between 0.59 and 0.72. Overall, this work illustrates how Py-GC-MS can lead to simple and adequate predictors of biochar stability. [Display omitted] • Stability Scores derived from Py-GC-MS can probe the stability of biochar in soil. • Py-GC-MS and principal component analysis were combined to set up Stability Scores. • Stability scores were selected by comparison alternative stability metrics. • Stability scores were calibrated with max R2 of 0.95. • Stability scores were validated with max R2 of 0.72. [ABSTRACT FROM AUTHOR]

Abstract: By using a tunable diode laser absorption spectrometer in conjunction with a cryogenically cooled multipath cell, we have revisited the air-induced pressure-broadening coefficients and the narrowing coefficients related to the Dicke effect, as well as the temperature dependences, for the R(18) and R(20) lines of the (10°1)I ←(00°0) vibrational band at 2.68μm of carbon dioxide. The selected transitions are used to probe in situ CO2 in the troposphere and the lower stratosphere by using balloon-borne laser sensors. The achieved measurements are thoroughly compared to existing former determinations. The impact of processing the in situ atmospheric CO2 spectra with this new set of molecular data is reported. [Copyright &y& Elsevier]

Abstract: Theoretical and experimental IR data are combined to gain insight into the methanol and ethanol conversion over an acidic H-SAPO-34 catalyst. The theoretical simulations use a large finite cluster and the initial physisorption energy of both alcohols is calculated. Dispersive contributions turn out to be vital and ethanol adsorbs stronger than methanol with approximately 14kJmol−1. Calculated IR spectra of the alcohols and of formed aromatic cations upon conversion are also analyzed and support the peak assignment of the experimental in situ DRIFT spectra, in particular for the C–H and Cs. Theoretical IR spectra of the gas phase compounds are compared with those of the molecules loaded in a SAPO cluster and the observed shifts of the peak positions are discussed. To get a better understanding of these framework–guest interactions, a new theoretical procedure is proposed based on a normal mode analysis. A cumulative overlap function is defined and enables the characterization of individual peaks as well as induced frequency shifts upon adsorption. [Copyright &y& Elsevier]

• Ethanol and acetic acid from syngas were converted into caproic acid by C. kluyveri. • Biochar (BC) and activated carbon (AC) foster bioproduction by C. kluyveri. • Differences between BC and AC translated into different fermentation profiles. • Biochar resulted in a higher initial production rate of caproic acid. • Activated carbon reduced pH-induced toxicity by partial adsorption of caproic acid. Syngas from biomass or steel mills can be fermented into a dilute stream of ethanol and acetic acid, which requires energy intensive distillation for product recovery. This can be circumvented by selective secondary fermentation of the syngas fermentation effluent to caproic acid as easier recoverable platform chemical with Clostridium kluyveri. Here, we explore the impact of biochar and activated carbon on this process. Changes during the fermentation with biochar or activated carbon were monitored, different doses were tested and the recyclability of biochar and activated carbon was assessed. Biochar decreased the lag phase and increased the caproic acid production rate (up to 0.50 g · L - 1 · h - 1 ). Upon recycling for subsequent fermentation, biochar retained this property largely. Activated carbon addition, especially at high dose, could potentially increase the conversion and selectivity towards caproic acid to 14.15 g · L - 1 (control: 11.01 g · L - 1 ) and 92% (control: 84%), respectively. [ABSTRACT FROM AUTHOR]

This work presents a continuous set-up for SCWO, which was operated at mild conditions (380 °C, 25 MPa, oxidant equivalence ratio of 2.0 and residence time of 26 s) to oxidize cellulose, lignin, and acetic acid as model compounds. The aim was to oxidize different organics consecutively to near completion in the same mild reaction conditions and set-up. These conditions can overcome some drawbacks associated to SCWO. To combine near complete oxidation with the applied mild process conditions, aqueous effluent from SCWO, containing intermediates from incomplete oxidation, was recycled for consecutive oxidation. Meanwhile, fresh feedstock was continuously fed to retain the process capacity. Upon recycling the aqueous effluent three to four times, depending on the feedstock, the oxidation efficiency increased from 63.9%, 45.3% and 28.3% in a single pass for cellulose, lignin, and acetic acid, respectively, to near 100%. The principle of effluent recirculation should allow a compact set-up to perform almost complete oxidation of different organics at mild conditions. The principles and effects of effluent recirculation are outlined, as well as practical consequences and perspectives of this novel principle to SCWO. • Supercritical water oxidation (SCWO) was performed at mild conditions. • Effluent recirculation was applied to improve organic oxidation efficiency. • The oxidizing capacity and oxygen consumption were favorable for recirculation. • A single and small setup at constant conditions oxidized different organics. [ABSTRACT FROM AUTHOR]

[Display omitted] • A green and effective strategy for biomass valorization was proposed. • Citric acid (CA) washing promoted furfural production during the torrefaction step. • CA washing increased levoglucosan yield to 3.76 times for W250-FP compared to R250-FP. • Torrefaction reduced acetic acid yield by 65% for W250-FP compared to WRaw-FP. Converting agricultural waste biomass into value-added chemicals is attractive. However, a low selectivity for target chemicals hinders practical applications. This study presents a stepwise strategy to convert sugarcane trash (ST) into furfural and levoglucosan with high selectivity. The approach includes citric acid washing to reduce mineral content in ST, followed by torrefaction at different temperatures (210 °C, 250 °C and 290 °C) in a tube furnace and then fast pyrolysis at 500 °C in a micro-reactor. This study highlights the valorization potential of the torrefaction liquid, an often overlooked by-product from torrefaction, through significantly increasing furfural selectivity during the torrefaction of washed ST. Furthermore, the vapors from subsequent fast pyrolysis of washed-torrefied ST exhibited reduced acetic acid content compared to that of solely washed ST, which is advantageous for minimizing the acidity of the resulting bio-oil. Moreover, fast pyrolysis of ST, treated with washing and torrefaction at 250 °C, achieved a high levoglucosan yield while maintaining a high furfural yield obtained in the prior torrefaction step. The findings of this study provide valuable insights into future research and industrial applications in agricultural waste biomass utilization. [ABSTRACT FROM AUTHOR]

2-methyl furan (MF) is a fuel additive with improved fuel characteristics compared to bio-ethanol. Unfortunately, the production of MF (from furfural (FF) hydrogenation) is not economically feasible. Interestingly, molten salts in biomass pyrolysis have shown to promote the formation of furans (mainly FF). Because molten salts hydropyrolysis could be an alternative route to both produce FF and convert it into MF, an assessment is indispensable. Molten salts pyrolysis and hydropyrolysis of pinewood and wheat straw and related model compounds were studied in a micro-reactor. The effect of hydropyrolysis process variables was assessed on the total detectable condensable vapors and MF formation. At low pressures (0.4 MPa), the chloride salts favored the production of FF and acetic regardless of the reaction atmosphere. Under a high pressure of hydrogen though (1.6 and 3.0 MPa), the conversion of FF to MF was enhanced through hydrogenation, hydrodeoxygenation and demethylation reactions. Molten salts hydropyrolysis at 350 °C and pressures of either 1.6 MPa (biomass mass fraction of 0.09) or 3.0 MPa (biomass mass fraction of 0.24) were optimal and yielded ca. 8 wt% to 9 wt% MF. Reaction temperatures >350 °C were unfavorable for the MF yield and instead promoted furfural decarbonylation to furan. [Display omitted] • Hydropyrolysis in molten salts highly promoted 2-methyl furan formation. • Targeted production of 2-methyl furan as fuel additive. • Higher pressure and biomass mass fraction are beneficial to product yield. • Product portfolio and yield in molten salts pyrolysis is carrier gas dependent. [ABSTRACT FROM AUTHOR]

Abstract: The relative contributions of the PSII-dependent and Nda2-dependent pathways for H2 photoproduction were investigated in the green microalga Chlamydomonas reinhardtii after suphur-deprivation. For this purpose, H2 gas production was compared for wild-type and Nda2-deficient cells with or without DCMU (a PSII-inhibitor) in the same experimental conditions. Nda2-deficiency caused a 30% decrease of the maximal H2 photoevolution rate observed shortly after the establishment of anoxia, and an acceleration of the decline of H2 photoevolution rate with time. DCMU addition to Nda2-deficient cells completely inhibited H2 photoproduction, showing that the PSII-independent H2 photoproduction relies on the presence of Nda2, which feeds the photosynthetic electron transport chain with electrons derived from oxidative catabolism. Nda2-protein abundance increased as a result of sulphur deprivation and further during the H2 photoproduction process, resulting in high rates of non-photochemical plastoquinone reduction in control cells. Nda2-deficiency had no significant effect on photosynthetic and respiratory capacities in sulphur-deprived cells, but caused changes in the cell energetic status (ATP and NADPH/NADP+ ratio). The rapid decline of H2 photoevolution rate with time in Nda2-deficient cells revealed a more pronounced inhibition of H2 photoproduction by accumulated H2 in the absence of non-photochemical plastoquinone reduction. Nda2 is therefore important for linking H2 photoproduction with catabolism of storage carbon compounds, and seems also involved in regulating the redox poise of the photosynthetic electron transport chain during H2 photoproduction. [Copyright &y& Elsevier]

• 24 biochar samples from 12 different feedstocks were characterised using five different chemical characterization methods. • Five feedstock independent indicators were identified based on the principal component analysis. • The highest treatment temperature was modelled using three feedstock-independent indicators. • The multilinear model and auxiliary correlations were positively validated with external datasets. Besides the feedstock composition, the highest treatment temperature (HTT) in pyrolysis is one of the key production parameters. The latter determines the feedstock's carbonization extent, which influences physicochemical properties of the resulting biochar, and in consequence its performance in industrial and agricultural applications. The actual HTT of biomass is difficult to measure in a reliable manner in many large-scale pyrolysis units (e.g., rotary kilns). Therefore, producers and end-users often rely on unreliable or biased information regarding this key production parameter that affects biochar quality. Data from indirect chemical assessment methods of biochar's carbonization extent correlate well with the highest treatment temperature. Therefore, this study demonstrates that the HTT can be accurately assessed posteriori and feedstock-independently via a simple-to-use model based on biochar characteristics related to the carbonization extent. For that purpose, 24 contrasting biochars from 12 different feedstocks produced in the most common production temperature range of 350−700 °C were analysed using 5 different established biochar chemical characterization methods. Then, experimental data was used to establish a multilinear regression model capable of correlating the HTT, which was successfully validated for external datasets. The correlation accuracy for biochars of various origin (lignocellulosic, manure) was satisfactorily high (R2adj. = 0.853, RSME =47 °C). The obtained correlation proved that the HTT can be predicted feedstock independently with the use of basic input data. It also provides a quick, simple, and reliable tool to verify the HTT of a given biochar. [ABSTRACT FROM AUTHOR]

A flexible Integrated Bayesian Multi-model Uncertainty Estimation Framework (IBMUEF) is presented to simultaneously quantify conceptual model structure, input and parameter uncertainty of a groundwater flow model. In this fully Bayesian framework, the DiffeRential Evolution Adaptive Metropolis (DREAM) algorithm with a novel likelihood function is combined with Bayesian Model Averaging (BMA). Four alternative conceptual models, representing different geological representations of an overexploited aquifer, have been developed. The uncertainty of the input of the model is represented by multipliers. A novel likelihood function based on a new heteroscedastic error model is included to extend the applicability of the framework. The results of the study confirm that neglecting conceptual model structure uncertainty results in unreliable prediction. Consideration of both model structure and input uncertainty are important to obtain confident parameter sets and better model predictions. This study shows that the IBMUEF provides more reliable model predictions and accurate uncertainty bounds. • Full Bayesian multi-model approach to quantify uncertainty of MODFLOW model. • Simultaneously quantifies model structure, input and parameter uncertainty. • DREAM with a novel likelihood function is combined with BMA. • Neglecting conceptual model uncertainty results in unreliable prediction. • Results in more reliable model predictions and accurate uncertainty bounds. [ABSTRACT FROM AUTHOR]

It is still unclear which outcome measures should be used in future clinical trials of adult patients with Becker Muscular Dystrophy (BMD) because of the paucity of studies and its heterogeneous progression. We evaluated a wide range of clinical and magnetic resonance imaging (MRI) outcome measures in 21 adults with BMD and 21 age- and sex-matched controls at baseline and after 9 and 18 months of follow-up. We used 6-point Dixon imaging with semi-automated 3D muscle segmentation to measure proton density fat fraction (PDFF) in all entire leg muscles (n=17 in thighs, n=10 in lower legs). In patients, PDFF increased significantly over 9 months in 14/17 thigh muscles, with a mean overall increase of 1.3±1.1% (p<0.001). This increase was significantly higher than that in controls (p=0.018), who increased 0.6±0.6% (p<0.001). Data of 18-months follow-up and lower leg PDFF are currently still under analysis. The north star ambulatory assessment (NSAA; -1.3 points, p=0.013), 32-point motor function measurement (MFM-32; -1.3%, p=0.017) and activity limitations scale (ActivLim; -0.3 logits, p=0.018) deteriorated significantly over 9 months. In the subgroup of patients with abnormal thigh muscle MRI findings, Biodex® isometric dynamometry measurement of peak torque decreased significantly in the quadriceps muscle group (-2.64 Nm, p=0.030), but not in the hamstrings. In all patients, the six-minute walk distance, 10-meter walk test, time to rise from floor test, time to climb 4 stairs test, timed up and go test, and Medical Research Council sum scores (150 and 60-points) did not change significantly over 9 months. All clinical outcome measures correlated strongly to total thigh PDFF at baseline. We conclude that analyzing PDFF in entire thigh muscles is a highly sensitive outcome measure to track progressive muscle fat replacement in patients with BMD, even after 9 months of follow-up. The NSAA, MFM-32 and ActivLim could also be used as outcome measures in future clinical trials. [ABSTRACT FROM AUTHOR]

This study outlines the effect of citric acid leaching on the quality and stability of fast pyrolysis bio-oils from sugarcane bagasse (SCB) and sugarcane trash (SCT). The quality of bio-oil was probed by GC-MS analysis, elemental composition, higher heating value, water and solids content, pH, dynamic viscosity and stability (ageing). Pyrolysis was performed at 500 °C in a fully controlled, continuously operated plant with a biomass throughput of ca. 300 g.hr−1. While citric acid leaching causes a decrease of the average bio-oil yield with 5%, it does not lead to a bio-oil with improved fuel-related properties. However, the bio-oil composition became more advantageous in light of its biorefining. Indeed, citric acid leaching led to an increased levoglucosan concentration – a promising platform chemical – of 17% for SCB and of to 35% for SCT (based on relative abundance in GC-MS). In tandem, the concentration of carboxylic acids and phenols in the bio-oil decreased after citric acid leaching, which is beneficial for downstream purification of levoglucosan. Regarding the non-condensable gases, CO and CO 2 represented between 88% and 91% by weight of the total non-condensable gases produced in pyrolysis. Therefore, the results of this study demonstrate that optimized biomass demineralization pretreatment with citric acid could produce bio-oil at high yield and rich in high-value chemical compounds like levoglucosan. Biomass demineralization pretreatment however, does not result in bio-oil with improved quality for fuel purposes, nor does it necessarily lead to bio-oil having higher stability. • Mild pretreatment with CA is effective in ash removal in sugarcane residues. • CA pretreated feedstock has higher bio-oil yields on pretreated feedstock basis. • Fresh/aged trash derived bio-oils have lower viscosity than bagasse derived bio-oils. • CA pretreatment holds no major benefit for bio-oil composition in terms of fuel use. • Major increase in anhydrosugar content after mild CA pretreatment of sugarcane residues. [ABSTRACT FROM AUTHOR]

Over recent years, pyrolysis has grown into a mature technology with added value for producing soil improvers. Further innovations of this technology lie in developing tailor-made products from specific feedstocks (or mixtures thereof) in combination with adjusted mixing ratio-temperature regimes. In this context, co-pyrolysis of pig manure (PM) and the invasive plant Japanese knotweed (JK) at different mixture ratios (w/w) of 3:1 (P3J1), 1:1 (P1J1), and 1:3 (P1J3) and varying temperatures (400–700 °C) was studied to address the low carbon properties and heavy metals (HMs) risks of manure-derive biochars and beneficially ameliorate the bio-invasion situation by creating value from the plant biomass. Co-pyrolysis of PM with JK increased by nearly 1.5 folds the fixed carbon contents in the combined feedstock biochars obtained at 600 °C compared with PM-derived biochar alone, and all combined feedstock biochars met the requirements for soil improvement and carbon sequestration. The total HMs in PM biochars were significantly reduced by adding JK. The combined feedstock biochar P1J1 generated at 600 °C was the most effective in transforming Cu and Zn into more stable forms, accordingly reducing the associated environmental risk of heavy metal leaching from the biochar. In addition, the accumulation of macronutrients can be an added benefit of the co-pyrolysis process, and P1J1-600 was also the biochar that retained the most nutrients (P, Ca, Mg, and K). [Display omitted] • Japanese knotweed addition improved the aromaticity of pig manure-derived biochar. • Co-pyrolysis reduced total Cu and Zn compared to pig manure-derived biochar. • Cu and Zn transformed to stable forms reduce the environmental risk of the biochar. • Co-pyrolysis retained higher nutrients than Japanese knotweed-derived biochar alone. • A 1:1 ratio of pig manure to Japanese knotweed at 600 °C was the optimal condition. [ABSTRACT FROM AUTHOR]

Limb-Girdle Muscular Dystrophy autosomal recessive type 12 (LGMDR12) is a rare hereditary muscle disease for which outcome measures are lacking. We evaluated intramuscular fat fraction as an outcome measure to track disease progression, to determine if this could be useful in future clinical trials to evaluate potential therapies. We prospectively performed a 6-point Dixon MRI of the thighs in 24 genetically confirmed, adult LGMDR12 patients and 24 age- and sex-matched healthy controls at baseline and after 1 and 2 years. The most affected muscles were the semimembranosus, biceps femoris long head and adductor magnus, respectively, and there was generally an increase in proton density fat fraction (PDFF) with increasing age and disease duration. Patients with intermediate stage thigh muscle fat replacement at baseline (PDFF 20-70%) already showed a significant increase in PDFF in 8/14 evaluated thigh muscles after one year. The standardized response mean (SRM) demonstrated a high responsiveness to change in PDFF for 6 individual muscles over 2 years in this group. We also found that tracking PDFF changes in individual muscles over time was more sensitive than PDFF measurements in muscle groups as a whole. In patients with early (<20%) or end stage (>70%) muscle fat replacement, or in the control group, PDFF did not increase significantly over two years of follow-up. Finally, we observed a moderately strong correlation between total thigh PDFF and the following clinical outcome measures at baseline: six-minute walk distance (6MWD), 10-meter walk test (10MWT), Medical Research Council (MRC) sum scores and Biodex® isometric dynamometry. We conclude that thigh muscle PDFF imaging is a sensitive outcome measure to track progressive muscle fat replacement in selected LGMDR12 patients even after one year of follow-up and should be included as an outcome measure in future clinical trials. [ABSTRACT FROM AUTHOR]

Abstract: In Chlamydomonas reinhardtii, prolonged anaerobiosis leads to the expression of enzymes belonging to various fermentative pathways. Among them, oxygen-sensitive hydrogenases (HydA1/2) catalyze the synthesis of molecular hydrogen from protons and reduced ferredoxin in the stroma. In this work, by analyzing wild type and mutants affected in H2 production, we show that maximal PSII photosynthetic electron transfer during the first seconds of illumination after a prolonged dark-anaerobiosis period is linearly related to hydrogenase capacity. Based on the specific chlorophyll fluorescence induction kinetics typical of hydrogenase-deficient mutants, we set up an in vivo fluorescence imaging screening protocol allowing to isolate mutants impaired in hydrogenase expression or activity, as well as mutants altered in related metabolic pathways required for energy production in anaerobiosis. Compared to previously described screens for mutants impaired in H2 production, our screening method is remarkably fast, sensitive and non-invasive. Out of 3000 clones from a small-sized insertional mutant library, five mutants were isolated and the most affected one was analyzed and shown to be defective for the hydrogenase HydG assembly factor. [Copyright &y& Elsevier]