dataesr/scientific-paragraphs-categorization huggingface dataset:
Results Structure of the holo-ScNsrR homodimer. ScNsrR crystallized as a dimer spanning a distance of about 80 Å, with monomers being related by a crystallographic twofold axis. It shows an elongated fold that is typical of the Rrf2 family of transcriptional regulators, comprising eight a-helices and two anti-parallel b-strands (Fig. 2a ). The X-ray structure parameters reveal high-temperature factors suggestive of a flexible and dynamic structure (Table  1 ). Nevertheless, the polypeptide chain was resolved for 137 of its 148 amino acid residues and forms two loosely interacting domains (residues 1-85 and 86-144, see Methods section). A comparison with available related structures in the Protein Data Bank revealed that although the DNA-binding N-terminal domain is the most conserved one its conformation is highly variable.
3 ). At the opposite side of the cluster Cys93 is exposed to solvent. The more buried Cys99 and Cys105 Sg atoms are hydrogen-bonded to the main chain N atoms of Leu101 and Arg108, respectively. The position of Cys105-Sg is further stabilized by the positive dipole moment of the a6 helix. Otherwise, the cluster environment is mainly hydrophobic, without H-bonds to the inorganic S atoms of the cluster. Anisotropic temperature factor analysis of the [4Fe-4S] cluster binding region at the dimer interface shows that the two monomers display orthogonally oriented agitation/disorder at this region (Supplementary Fig. 2 ). Holo-ScNsrR appears to be the first structurally characterized protein with a [4Fe-4S] cluster that is asymmetrically bound by ligands from two different subunits as indicated by our examination of all the other [4Fe-4S] cluster-containing protein structures found in the Protein Data Bank  18.
The fourth iron of the D8A [4Fe-4S] cluster is likely bound by a labile solvent molecule, or some other loosely-associated small molecule anion, in the absence of a coordinating amino acid residue within binding distance. Such a ligand would be more labile than protein-bound thiolate or carboxylate ligands, and more readily displaced by NO. The greater sensitivity of wild type ScNsrR compared to D8C is also consistent with the greater lability of the coordinating carboxylate compared to a Cys residue  19, 20. Possible initial NO-binding site at the iron-sulfur cluster. Figure  5  shows a cavity map with a possible access path for NO, which is consistent with the data presented above. This path points at Asp8, the non-cysteinyl ligand to the [4Fe-4S] cluster. It is likely that the same access pathway at the dimer interface (Fig.
Methods Purification of Streptomyces coelicolor NsrR variants. All plasmids were purchased from Genscript (Supplementary Methods). C-terminally His-tagged ScNsrR proteins (wild type [UniProt accession code: Q9L132] and variant proteins D8A, D8C and C93A/C99A/C105A or 3CA) were overexpressed in E. coli BL21DE3 (New England Biolabs Inc). Briefly, bacterial cultures were grown at 37 °C, in LB broth supplemented with the appropriate antibiotic, until A 600 nm reached 0. 6-0. 8 (ref. 3). Cultures were then cold shocked on ice for 18 min. Protein overproduction was initiated by the addition of 10 mM isopropyl b-D-thiogalactopyranoside and cultures incubated at 30 °C. After 50 min, cultures were supplemented with 200 mM ferric ammonium citrate, 50 mM L-methionine and incubated for a further 3. 5 h (ref.
The somewhat higher stoichiometry of reaction observed here for the His-tagged proteins compared to that previously observed for non-tagged NsrR 8 is attributed to a minor unknown side reaction that resulted in a small amount of insoluble product. UV-visible stopped-flow experiments were performed with a Pro-Data upgraded Applied Photophysics Bio-Sequential DX. 17MVspectrophotometer, with a 1 cm path length cell. Absorption changes were detected at a single wavelength (357 nm). Before use, the stopped-flow system was flushed with 30 ml of anaerobic assay buffer and experiments were carried out using gas tight syringes (Hamilton). All solutions used for stopped-flow experiments were stored and manipulated inside an anaerobic glovebox (Belle Technology). Fitting of kinetic data at 357 nm to single exponential functions was performed using Origin (version 8, Origin Labs).
Full mass spectra (m/z 500-3500) were recorded for 5 min with parameters as follows: dry gas flow 4 l min À 1 , nebuliser gas pressure 0. 8 Bar, dry gas 180 °C, capillary voltage 2,750-4,500 V, offset 500 V, ion energy 5 eV, collision RF 200 Vpp, collision cell energy 10 eV. Spectra were combined, processed using the ESI Compass 1. 3 Maximum Entropy deconvolution routine in Bruker Compass Data analysis 4. 1 (Bruker Daltonik, Bremen, Germany). Exact masses are reported from peak centroids representing the isotope average neutral mass. For apo-proteins, these are derived from m/z spectra, for which peaks correspond to [M þ nH] n þ /n. For cluster-containing proteins, where the cluster contributes charge, peaks correspond to [M þ FeS x þ þ (n À x)H] n þ /n, where M is the molecular mass of the protein, FeS is the mass of the iron-sulfur cluster of x þ charge, H is the mass of the proton and n is the total charge.
All flash-cooled ScNsrR crystals were kept under a cold (100 K) N 2 stream during X-ray data collection. The presence of Fe was confirmed by an X-ray absorption spectrum, measured with a Roentec X-Flash multichannel analyzer at beamline BM30a of the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. The X-ray wavelength providing the maximum iron anomalous signal was determined to be 1. 7414 Å with the program CHOOCH  31. Subsequently, highly redundant 2. 6 Å resolution X-ray diffraction data were collected at this wavelength from a single crystal with an ADSC Quantum 315r detector at the same beamline (Table  1 , first column). These and all subsequent data obtained from other crystals were processed with the XDS package  32  ) and scaled with the AIMLESS program  33  of the CCP4 package  34.
Next, we used the PHENIX program package  35  with these data to locate individual Fe sites of the [4Fe-4S] cluster with a Hybrid Substructure Search, to obtain single anomalous dispersion (SAD) phases with a figure of merit of 0. 321 by refining the Fe parameters and using density modification for further phase improvement. During this process the space group was assigned as P6 5 22. The resulting phases were of sufficient quality to obtain an interpretable 2. 6 Å resolution electron density map that allowed us to trace most of the polypeptide chain with the program COOT  36. Data were collected to 1. 95 Å resolution from another crystal, at a remote wavelength of 0. 984 Å, with a Dectris Pilatus 6M-F detector (Table  1 , second column) at ESRF beamline ID23. These data were processed and scaled as described above and used for model refinement.
Initial positional, TLS and individual B-factor refinement was done with the program phenix. refine  37 , which automatically determined two TLS groups corresponding to residues 2-85 and 86-144 to model anisotropic motions of these two domains. Final refinement was performed with the program Refmac5 (ref. 38). Refinement cycles were alternated with manual corrections using COOT. No outliers in the Ramachandran plot were found for the refined model consisting of residues 2-58 and 65-144. However, due to a high degree of disorder in the structure, several exposed loops and residues are poorly defined in the electron density map. Supplementary Fig. 11  shows the final electron density map obtained for the DNA-binding a-helix 3. The best crystal of the triple 3CA (C93A/C99A/C105Q) apo-ScNsrR variant provided diffraction data to 3.
9 Å resolution collected at a wavelength of 0. 9677 Å with an Eiger 4M detector at ESRF beamline ID30-A3. These data were assigned by XDS to a trigonal space group. Starting from the refined structure of a holo-ScNsrR monomer, a molecular replacement solution was found by the program PHASER  39  , which identified the presence of 5 apo-ScNsrR copies in the asymmetric unit and determined the crystal symmetry to be P3 2 21 (Table  1 , third column). In the trigonal crystal apo-ScNsrR molecules pack as a wide cylinder around a large internal solvent region of about 100 Å diameter. Four of the five apo 3CA-ScNsrR molecules form two non-crystallographic symmetry (ncs)-related dimers while the 5th one forms a third dimer with a neighboring monomer related by twofold crystallographic symmetry. The validity of the found molecular replacement solution was confirmed by the structural similarity of all three dimers to the functional holo-ScNsrR dimer.
The resulting apo 3CA-ScNsrR model, consisting of residues 2-59 and 66-134, is much more disordered than its holo counterpart, as indicated by an average calculated B-factor of more than 200 Å 2. Supplementary Figure  12  illustrates how this structure fits to the density-modified map obtained after five cycles of a final 10-fold multi-crystal averaging and solvent flattening procedure. Accessible surface and secondary structure elements of the refined NsrR structure were determined with the dssp program  40  , related structures were superimposed by secondary structure with COOT and this program was also used to visualize anisotropic domain motions (Fig. S2 ). A cavity map was calculated with the in-house developed program cavenv, as incorporated in the CCP4 package  34. Compilations of all the programs mentioned above were provided by SBGrid  41.
Acknowledgements The Metalloproteins Unit members thank the  CEA , the  CNRS  and the  Universite Ǵrenoble-Alpes  for institutional funding and the beamlines BM30a,  ID30-A3  and  ID23  of the  European Synchrotron Radiation Facility (ESRF)  for help with X-ray data collection. This work was partially supported by  FRISBI  ( ANR-10-INSB-05-02 ) within the  Grenoble Partnership for Structural Biology  (PSB). The  University of East Anglia  authors' work is supported by the  UK's Biotechnology and Biological Sciences Research Council  ( BB/J003247/1  and  BB/L007673/1 ) and by the  Royal Society  through the award of a  Newton International Fellowship  to  E. L. D. They  thank  Dr Myles Cheesman  for access to spectrophotometers.
The final in-situ synthesis of the CuInS 2 -nanoparticles (CuInS 2 -NPs) was done by thermal conversion (195°C over a period of 30 min, heating rate = 10°C/min) of copper and indium xanthate on a programmable heating plate. ATR-IR spectroscopy. The infrared spectra were recorded with an ALPHA FT-IR spectrometer (Bruker; Billerica, MA, USA). For the measurement an attenuated total reflection (ATR) attachment was used with 48 scans at a resolution of 4 cm -1 and a scan range between 4000 and 400 cm -1. The samples were prepared on Au-coated glass slides (SPR102-AU). The data were analyzed with OPUS 4. 0 software.
The profile was set to hills and valleys. The diamond stylus had a radius of 12. 5 µm and the force was 3 mg with a resolution of 0. 333 μm/sample and a measurement range of 6. 5 μm. This measured profile was then used to determine the thickness. Surface free energy. To determine the static contact angle and the surface free energy (SFE) a drop shape analysis system DSA100 (Krüss GmbH, Hamburg, Germany) with a T1E CCD video camera (25 fps) and the DSA1 v 1. 90 software was used. For the measurements 3 μL droplets of Milli-Q water (≥18 MΩcm -1 ) and diiodomethane as test liquids in the sessile drop modus at 25 °C were deposited on the substrates. The dispense rate was adjusted to 200 µL/min and the time before the image was captured was 2 seconds. Each sample was measured at least three times.
5 nm -1 (GISAXS). The X-ray energy was 8 keV. For the time-resolved measurements, the nanocomposite samples were placed in a heating cell (DHS 1100 from Anton Paar GmbH, Graz, Austria) equipped with a custom-made dome with Kapton polyimide film windows and were heated from 30 °C up to 230 °C at a heating rate of approx. 10 °C min -1 under nitrogen atmosphere. During the temperature scan, data were recorded with framing rate of 6 s using a Pilatus 1M detector (Dectris). For detection of the GIWAXS signal, a Pilatus 100K detector from Dectris was used. The angular calibration of the detectors was carried out using silver behenate powder (d-spacing of 58. 38 Å) and p-bromo benzoic acid, respectively.
The characteristic values of the prepared solar cells were determined from IV curves recorded using a Keithley 2400 SourceMeter, a custom made Lab-View software and a Dedolight DLH400D lamp providing a spectrum very similar to AM1. 5G. The light intensity was set to 100 mW/cm 2 (determined using a KippZonen-CMP-11 pyranometer, no spectral mismatch was considered). The EQE spectrum was measured using a Multimode4 monochromator (AMKO) equipped with a Xenon lamp and a Keithley 2400 source meter.
After the heat treatment and the associated formation of CuInS 2 nanoparticles, the films retain their hydrophobic character (CA ~90°). Simultaneously, the surface free energies increased depending on the nanoparticle concentration. This effect may originate from roughness effects since SFE increases with increasing CuInS 2 -NP concentrations in the films. Moreover, these data also confirm the stability of the TMSC during the heat treatment regardless of the starting xanthate concentration. The UV-VIS absorption of the film was determined to prove the suitability of the hybrid material for the application as an absorber material in a nanocrystal solar cell. The untreated film showed a distinctive absorption band for CuXa/InXa starting at ca. 420 nm, which vanished after the heat treatment (see Fig.
Acknowledgements Part of the work was supported by the  People Programme (Marie Curie Actions -Career Integration Grants ) of the European Union's  Seventh Framework Programme  ( FP7/2007-2013)  under  REA  grant agreement n°618158 (PhotoPattToCell), the  H2020-FET-open  project  CONQUER  under grant agreement  n°665172  and  OEAD/WTZ Amadeus programm  (project number  FR 16/2014 ). Elettra Sincrotrone Trieste  is acknowledged for providing synchrotron radiation at the Austrian SAXS beamline. The authors thank  Jürgen Sattelkow  for technical support.
METHODOLOGY The study is carried out in four main phases: 1. Obtaining CSP market and CSPonD benchmark cost information:  Carrying out CSP market cost analyses to obtain cost per major component;  Establishing total cost for the existing 100 kW th beam-down and CSPonD Demo system installed at the MISP in the UAE. 2. Developing an optical optimization model using the MUEEN code  [4] , to design an up-scaled CSPonD system using a hillside heliostat field for a given power output; 3. Calculating the optical efficiency of each upscaled system using TracePro; 4. Determining total cost and analyzing different economic indicators for the scaled-up system based on multi-objective optimisation using DYESOPT.
Optical Efficiency Calculations The five cases are run in the ray tracing software TracePro 7. 57  [12]  to create a matrix calculating overall optical efficiency (the product of the cosine, shading, blocking and spillage efficiencies) based on differing sun elevations and azimuths. An in-house code is written to compute efficiency based on the flux reported by TracePro on each surface after each simulation. The heliostats are modeled as flat, perfect mirrors oriented with an azimuth-elevation scheme, forming a south-facing field, and the receiver is simulated being placed at the z-axis of the model. The sun is represented as a large, flat circular source above the field and each ray direction is determined on the basis of the solar angular distribution included in TracePro.
ACKNOWLEDGEMENTS This work is funded by the  Masdar Institute/MIT  collaborative flagship project, grant #  FR2014-000002. Research at Masdar Institute  is supported by the  Government of Abu Dhabi  to help fulfill the vision of the late  President Sheikh Zayed bin Sultan Al Nayhan for sustainable development and empowerment of the UAE  and humankind. Masdar Institute and MIT acknowledge in alphabetic order:  Dongfang Electric Corporation  for designing and providing the molten salt-air heat exchanger system,  National Instruments  and  Parker/Sunpower  for donating part of the instrumentation, control, and motion systems, and SQM for kindly providing the nitrate salts for the prototype.
The Q nonsol and Q aux have been calculated with SOLCAL  [22]. SOLCAL is free software available online, which is recommended by European Commission  [23]  for calculating the non-solar energy needed in the package and includes several technical parameters for the solar devices. III' = (Q aux × 2. 5)/(220 × Q ref ) 0. 109 -Formula from Regulation 811/2013 (Annex IV, 6b) Solar contribution = (1. 1 × I' -10%) × II' -III' -I' 2. 69 % Formula from Regulation 811/2013 (Figure  5 ) Table  6  shows the results for the water heating energy efficiency and class of the DHW system and the seasonal space heating energy efficiency and class of the SH system in the case study, when implementing the calculation scheme from Figure  5  of Regulation 811/2013.
CMG and freeze casted rCMG characterization. The lateral dimensions of the CMG flakes were measured using optical microscopy and ImageJ software over 100 flakes deposited on a silicon wafer. The CMG content in the slurry was estimated from freeze-dried CMG samples. Preparation of rCMG/ceramic composites. The rCMG/ceramic composites were obtained by infiltrating the rCMG networks with a ceramic precursor mixture followed the subsequent polymer-to-ceramic conversion. Infiltration was done in a vacuum caster by immersing the rCMG networks in a solution of polymethylsiloxane (MK Silres-Wacker Chemistry) and a cross-linkable processing aid: methyltriethoxysilane (Sigma Aldrich). Components were mixed in a 2:1 ratio with a small amount (0. 1 wt. %) of dibutyltin dilaurate as catalyst. The immersed networks were left to dry in ambient conditions and the polymer formed a gel within 2 days.
6 eV). An X-ray spot of B400 Â 800 mm ellipse shape was used and three different areas were spotted. Core level C1s, C KLL , O1s, N1s,Mn1s, S2p, Na1s spectra were acquired using a pass energy of 200 eV and high regions at 40 eV. Casa XPS was used for data interpretation. Shirley or two-point linear background subtractions were employed depending on background shape. Scofield cross-sections were used as relative sensitivity factors in the calculation of the atomic percentages (with RSF of C 1 s ¼ 1. 000). Peaks were fitted using GL(30) lineshapes; a combination of a Gaussian (70%) and Lorentzian (30%). All XP spectra were charge corrected by referencing the fitted contribution of C-C graphitic like carbon in the C 1 s signal to 284. 6 eV. The atomic percentages were calculated from the peak areas in the acquired high resolution C 1 s and O 1 s photoelectron spectra using Scofield sensitivity factors.
Acknowledgements We acknowledge the  EPSRC Grant Graphene 3D Networks  ( EP/K01658X/1 ),  EPSRC  founded  Center for Advanced Structural Ceramics (CASC) at Imperial College London. O. T. P. thanks  Nanoforce Technology Ltd. for their facilities and V. G. R. thank the  European Commission  ( FP7-Marie Curie Intra-European Fellowship GRAPES ). C. F. thanks the  European Commission  funding under the 7th  Framework Programme (Marie Curie Initial Training Networks ; grant number:  289958 ,  Bioceramics for Bone Repair ). N. N. acknowledges the funding from  Imperial College Junior Research Fellowship. X-ray photoelectron spectra were obtained at the  National EPSRC XPS Users' Service (NEXUS) at Newcastle University , an  EPSRC Mid-Range Facility. We acknowledge  Dr. I. J. Villar-Garcia  support on XPS data processing and analysis.
Results Thermodynamical approach and experimental dataset. In the present study, calculations were focused on the electron-accepting fermentative species, by considering the following scenario: first, electrons are supplied to such species through EET mechanisms  19, 20  and reduce membrane-bound or intracellular redox active proteins (RAP ferm , e. g. cytochromes, ferredoxin) in the fermentative bacteria. For calculation purposes, the apparent potential at which electrons can be used by the electron-accepting bacteria will be referred to as E RAP , whatever the considered EET mechanism. In a second step, oxidation of these reduced RAP ferm is coupled to an electron dissipation pathway where part of the fermentation substrate (e. g. butanol production from glucose) is used to maintain the intracellular redox balance.
To assess the dependency of the growth yield on the RAP ferm redox potential, three experimental datasets showing extracellular electron uptake by a fermentative species together with a decreased of the growth yields were revisited. These three cases were selected as they are the only studies dealing with electro-fermentation where complete characterization of the metabolic products as well as bacterial biomass quantification were provided. The first one concerns glycerol fermentation by C. pasteurianum in co-culture with G. sulfurreducens as electron-donating species  18. The two other studies deal with glucose cathodic electro-fermentation by C. pasteurianum  13  and Propionibacterium freudenreichii  8. Carbon mass balances retrieved from these studies are provided in Fig. 2. In these three experiments, it could be observed that EET enhanced the production of 1,3-propanediol, butanol and propionate for the three studies, respectively.
g. OmcF, ubiquinone)  20, 22  would make the electron dissipation pathway endergonic with subsequent drastic decrease of growth yields. Model parameter fitting to experimental data. As full characterization of substrate, metabolites and biomass production are provided in the three selected experimental studies, it was possible to carry out a thermodynamical state analysis using these actual experimental data. Based on these datasets and assuming that ΔG dis during fermentation and fermentation + EET were equal, unique values of α and E RAP were fitted for each study (see Method section and Supplementary material). The coupling parameter α calculated from experimental mass balances for the three cases is 1. 34, 5. 26 and 89. 63% for the C. pasteurianum electro-fermentation, C. pasteurianum co-culture and P.
e. fermentation + EET). In the case of Choi et al. 13  , data were retrieved from their Supplementary Table  2  providing electron and carbon mass balances for fermentation and fermentation + EET (referred as "control" and "BES", respectively). Finally, data from Moscoviz et al. 18  were extracted from Fig. 3  showing electron and carbon mass balances for pure culture of C. pasteurianum (fermentation) and co-culture of C. pasteurianum with G. sulfurreducens (fermentation + EET). Although mass balances from these datasets closed at nearly 100%, the raw stoichiometric balances were corrected using HCO 3 and H 2 as adjustment variables to obtain a carbon and electron recovery of 100%. The stoichiometric calculations are provided as Supplementary materials and the resulting corrected carbon mass balances are displayed in Fig.
2. To assess the model parameters α and E RAP from these datasets, the amounts of substrate consumed for global catabolism and for anabolism were first estimated based on bacterial biomass quantification. In the case of Choi et al. 13  , bacterial biomass production during fermentation + EET corresponded to 10. 4% of the initial carbon input. According to equation 8 (glucose anabolism), the molar fraction of substrate dedicated to biomass synthesis was also 10. 4% in this condition, meaning that 89. 6% of the initial carbon was used for global catabolism. Therefore, it was possible to calculate the α index (i. e. the fraction of fermentation substrate used for the electron dissipation reaction, normalized on substrate consumption for global catabolism) using quantification of the extracellular electron input.