Takens-inspired neuromorphic processor: a downsizing tool for random recurrent neural networks via feature extraction

We describe a new technique which minimizes the amount of neurons in the hidden layer of a random recurrent neural network (rRNN) for time series prediction. Merging Takens-based attractor reconstruction methods with machine learning, we identify a mechanism for feature extraction that can be leveraged to lower the network size. We obtain criteria specific to the particular prediction task and derive the scaling law of the prediction error. The consequences of our theory are demonstrated by designing a Takens-inspired hybrid processor, which extends a rRNN with a priori designed delay external memory. Our hybrid architecture is therefore designed including both, real and virtual nodes. Via this symbiosis, we show performance of the hybrid processor by stabilizing an arrhythmic neural model. Thanks to our obtained design rules, we can reduce the stabilizing neural network's size by a factor of 15 with respect to a standard system.Comment: 12 pages, 8 figure

New evaluation of thermal neutron scattering libraries for light and heavy water

In order to improve the design and safety of thermal nuclear reactors and for verification of criticality safety conditions on systems with significant amount of fissile materials and water, it is necessary to perform high-precision neutron transport calculations and estimate uncertainties of the results. These calculations are based on neutron interaction data distributed in evaluated nuclear data libraries. To improve the evaluations of thermal scattering sub-libraries, we developed a set of thermal neutron scattering cross sections (scattering kernels) for hydrogen bound in light water, and deuterium and oxygen bound in heavy water, in the ENDF-6 format from room temperature up to the critical temperatures of molecular liquids. The new evaluations were generated and processable with NJOY99 and also with NJOY-2012 with minor modifications (updates), and with the new version of NJOY-2016. The new TSL libraries are based on molecular dynamics simulations with GROMACS and recent experimental data, and result in an improvement of the calculation of single neutron scattering quantities. In this work, we discuss the importance of taking into account self-diffusion in liquids to accurately describe the neutron scattering at low neutron energies (quasi-elastic peak problem). To improve modeling of heavy water, it is important to take into account temperature-dependent static structure factors and apply Sköld approximation to the coherent inelastic components of the scattering matrix. The usage of the new set of scattering matrices and cross-sections improves the calculation of thermal critical systems moderated and/or reflected with light/heavy water obtained from the International Criticality Safety Benchmark Evaluation Project (ICSBEP) handbook. For example, the use of the new thermal scattering library for heavy water, combined with the ROSFOND-2010 evaluation of the cross sections for deuterium, results in an improvement of the C/E ratio in 48 out of 65 international benchmark cases calculated with the Monte Carlo code MCNP5, in comparison with the existing library based on the ENDF/B-VII.0 evaluation

Model predictive control: a review of its applications in power electronics

Model-based predictive control (MPC) for power converters and drives is a control technique that has gained attention in the research community. The main reason for this is that although MPC presents high computational burden, it can easily handle multivariable case and system constraints and nonlinearities in a very intuitive way. Taking advantage of that, MPC has been successfully used for different applications such as an active front end (AFE), power converters connected to resistor inductor RL loads, uninterruptible power supplies, and high-performance drives for induction machines, among others. This article provides a review of the application of MPC in the power electronics area

Calculation of kinetic parameters βeff and Λ with modified open source Monte Carlo code OpenMC(TD)

This work presents the methodology used to expand the capabilities of the Monte Carlo code OpenMC for the calculation of reactor kinetic parameters: effective delayed neutron fraction βeff and neutron generation time Λ. The modified code, OpenMC(Time-Dependent) or OpenMC(TD), was then used to calculate the effective delayed neutron fraction by using the prompt method, while the neutron generation time was estimated using the pulsed method, fitting Λ to the decay of the neutron population. OpenMC(TD) is intended to serve as an alternative for the estimation of kinetic parameters when licensed codes are not available. The results obtained are compared to experimental data and MCNP calculated values for 18 benchmark configurations.Fil: Romero Barrientos, J.. Comision Chilena de Energia Nuclear; Chile. Universidad de Chile; ChileFil: Marquez Damian, Jose Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. European Spallation Source; SueciaFil: Molina, F.. Comision Chilena de Energia Nuclear; Chile. Universidad Andrés Bello; ChileFil: Zambra, M.. Comision Chilena de Energia Nuclear; Chile. Universidad Diego Portales; ChileFil: Aguilera, P.. Comision Chilena de Energia Nuclear; Chile. Universidad de Chile; ChileFil: López Usquiano, F.. Comision Chilena de Energia Nuclear; Chile. Universidad de Chile; ChileFil: Parra, B.. Instituto de Física Corpuscular; EspañaFil: Ruiz, A.. Comision Chilena de Energia Nuclear; Chile. Universidad de Chile; Chil

A New Field Protocol for Monitoring Forest Degradation

Forest degradation leads to the gradual reduction of forest carbon stocks, function, and biodiversity following anthropogenic disturbance. Whilst tropical degradation is a widespread problem, it is currently very under-studied and its magnitude and extent are largely unknown. This is due, at least in part, to the lack of developed and tested methods for monitoring degradation. Due to the relatively subtle and ongoing changes associated with degradation, which can include the removal of small trees for fuelwood or understory clearance for agricultural production, it is very hard to detect using Earth Observation. Furthermore, degrading activities are normally spatially heterogeneous and stochastic, and therefore conventional forest inventory plots distributed across a landscape do not act as suitable indicators: at best only a small proportion of plots (often zero) will actually be degraded in a landscape undergoing active degradation. This problem is compounded because the metal tree tags used in permanent forest inventory plots likely deter tree clearance, biasing inventories toward under-reporting change. We have therefore developed a new forest plot protocol designed to monitor forest degradation. This involves a plot that can be set up quickly, so a large number can be established across a landscape, and easily remeasured, even though it does not use tree tags or other obvious markers. We present data from a demonstration plot network set up in Jalisco, Mexico, which were measured twice between 2017 and 2018. The protocol was successful, with one plot detecting degradation under our definition (losing greater than 10% AGB but remaining forest), and a further plot being deforested for Avocado (Persea americana) production. Live AGB ranged from 8.4 Mg ha–1 to 140.8 Mg ha–1 in Census 1, and from 0 Mg ha–1 to 144.2 Mg ha–1 Census 2, with four of ten plots losing AGB, and the remainder staying stable or showing slight increases. We suggest this protocol has great potential for underpinning appropriate forest plot networks for degradation monitoring, potentially in combination with Earth Observation analysis, but also in isolation

A luminescence study of Cu2ZnSnSe4/Mo/glass films and solar cells with near stoichiometric copper content

Cu2ZnSnSe4 (CZTSe) is one of the leading candidates for the absorber layer in sustainable solar cells. Thin films of CZTSe with a near stoichiometric [Cu]/[Zn  +  Sn] were used to produce solar cells with conversion efficiency η  =  6.4% by a standard solar cell processing including KCN etching and the deposition of CdS and ZnO. Both CZTSe films and solar cells were examined using photoluminescence (PL) to analyse the nature of radiative recombination and photoluminescence excitation (PLE) at 4.2 K to determine the bandgap (E g ). Low temperature PL spectra of the films reveal an intense band P1 at 0.81 eV and a low intensity band P2 at 0.93 eV. Their temperature and excitation intensity dependencies suggest that they both involve recombinations of free electrons with holes localised at acceptors with the energy level influenced by potential fluctuations in the valence band. We associate P1 and P2 with different fractions of CZTSe: with a lower and higher degree of order of Cu and Zn on the cation sub-lattice, respectively. Device processing reduced the intensity of P1 by 2.5 whereas the intensity of P2 increased by a 1.5. We assign this to a low temperature annealing due to CdS and ZnO deposition which increased the fraction of CZTSe with high degree of Cu/Zn order and decreased the fraction with low degree of Cu/Zn order. Device processing increased E g , blue shifted P1, decreased its width, j-shift and the mean depth of potential fluctuations. These can also be related to the annealing and/or KCN etching and the chemical effect of Cd, due to CdS replacing copper at the CdS-CZTSe interface layer. Processing induced a new broad band P3 at 1.3 eV (quenching with E a = 200 meV) which we attributed to defects in the CdS layer

Effects of selenisation temperature on photoluminescence and photoluminescence excitation spectra of ZnO/CdS/Cu2ZnSnSe4/Mo/glass

The effect of solar cell processing (including etching in KCN along with deposition of CdS and ZnO) on photoluminescence (PL) spectra and bandgap Eg (measured at 4.2 K by photoluminescence excitation) of Cu2ZnSnSe4 films, produced by selenising metallic precursors at 450 °C, 500 °C and 550 °C, was studied. Temperature and excitation intensity analysis of the P1 dominant band in the PL spectra of solar cells suggests that after processing this band still can be assigned to the free-to-bound recombination of free electrons with holes bound at deep acceptor levels influenced by valence band-tails. However processing increased the intensity of P1 and blue shifted it. The strongest effect was observed for the film selenised at 500 °C. For the film selenised at 450 °C the blue shift and increase in the intensity were smaller and only a slight intensity rise was found for the film selenised at 550 °C. The intensity increase we assign to a reduction in the concentration of non-radiative recombination centers on the surface because of the etching and changes in doping due to inter-diffusion of Cd, S, Se and Zn after the deposition of CdS. Such an inter-diffusion depends on the elemental composition of the films defining the chemistry of defects and influencing Eg which increased in the film selenised at 500 °C but decreased in the other films. Processing increased the P1 shift rate (j-shift) with excitation power change in all the films demonstrating a higher compensation degree in the solar cells which is consistent with the formation of an interface layer containing new donors CdCu

Calcium-dependent oligomerization of CAR proteins at cell membrane modulates ABA signaling

[EN] Regulation of ion transport in plants is essential for cell function. Abiotic stress unbalances cell ion homeostasis, and plants tend to readjust it, regulating membrane transporters and channels. The plant hormone abscisic acid (ABA) and the second messenger Ca2+ are central in such processes, as they are involved in the regulation of protein kinases and phosphatases that control ion transport activity in response to environmental stimuli. The identification and characterization of the molecular mechanisms underlying the effect of ABA and Ca2+ signaling pathways on membrane function are central and could provide opportunities for crop improvement. The C2-domain ABA-related (CAR) family of small proteins is involved in the Ca2+-dependent recruitment of the pyrabactin resistance 1/PYR1like (PYR/PYL) ABA receptors to the membrane. However, to fully understand CAR function, it is necessary to define a molecular mechanism that integrates Ca2+ sensing, membrane interaction, and the recognition of the PYR/PYL interacting partners. We present structural and biochemical data showing that CARs are peripheral membrane proteins that functionally cluster on the membrane and generate strong positive membrane curvature in a Ca2+-dependent manner. These features represent a mechanism for the generation, stabilization, and/or specific recognition of membrane discontinuities. Such structures may act as signaling platforms involved in the recruitment of PYR/PYL receptors and other signaling components involved in cell responses to stress.A.A. and J.A.M. thank the European Syncrotron Radiation Facility and EMBL for access to the synchrotron radiation source. This work was funded by Ministerio de Economia y Competitividad (MINECO) Grants BFU2014-59796-R (to A.A.), BFU2011-28184-C02 (to M.J.S.-B.), and BIO2014-52537-R (to P.L.R.) and Comunidad de Madrid Grant S2010/BMD-2457 (to A.A and M.M.). M.J.S.-B. is supported by Ramon y Cajal Contract RYC-2008-03449 from MINECO and M.D. by a fellowship from Senacyt-Ifarhu. Access to the High Throughput Crystallization facility at European Molecular Biology Laboratory (EMBL) Grenoble was supported by the European Community's Seventh Framework Programme through the Protein Production Platform project (P-CUBE) Grant 227764.Diaz, M.; Sanchez-Barrena, MJ.; Gonzalez Rubio, JM.; Rodríguez Solovey, LN.; Fernández, D.; Antoni-Alandes, R.; Yunta, C.... (2016). Calcium-dependent oligomerization of CAR proteins at cell membrane modulates ABA signaling. Proceedings of the National Academy of Sciences. 113(3):E396-E405. https://doi.org/10.1073/pnas.1512779113SE396E4051133Serrano, R., & Rodriguez-Navarro, A. (2001). Ion homeostasis during salt stress in plants. Current Opinion in Cell Biology, 13(4), 399-404. doi:10.1016/s0955-0674(00)00227-1Bassil, E., & Blumwald, E. (2014). The ins and outs of intracellular ion homeostasis: NHX-type cation/H + transporters. Current Opinion in Plant Biology, 22, 1-6. doi:10.1016/j.pbi.2014.08.002Batistič, O., & Kudla, J. (2012). Analysis of calcium signaling pathways in plants. Biochimica et Biophysica Acta (BBA) - General Subjects, 1820(8), 1283-1293. doi:10.1016/j.bbagen.2011.10.012Cutler, S. R., Rodriguez, P. L., Finkelstein, R. R., & Abrams, S. R. (2010). Abscisic Acid: Emergence of a Core Signaling Network. Annual Review of Plant Biology, 61(1), 651-679. doi:10.1146/annurev-arplant-042809-112122McAinsh, M. R., Brownlee, C., & Hetherington, A. M. (1990). Abscisic acid-induced elevation of guard cell cytosolic Ca2+ precedes stomatal closure. Nature, 343(6254), 186-188. doi:10.1038/343186a0Maierhofer, T., Diekmann, M., Offenborn, J. N., Lind, C., Bauer, H., Hashimoto, K., … Hedrich, R. (2014). Site- and kinase-specific phosphorylation-mediated activation of SLAC1, a guard cell anion channel stimulated by abscisic acid. Science Signaling, 7(342), ra86-ra86. doi:10.1126/scisignal.2005703Allen, G. J., Kwak, J. M., Chu, S. P., Llopis, J., Tsien, R. Y., Harper, J. F., & Schroeder, J. I. (1999). Cameleon calcium indicator reports cytoplasmic calcium dynamics in Arabidopsis guard cells. The Plant Journal, 19(6), 735-747. doi:10.1046/j.1365-313x.1999.00574.xLee, S. C., Lan, W.-Z., Kim, B.-G., Li, L., Cheong, Y. H., Pandey, G. K., … Luan, S. (2007). A protein phosphorylation/dephosphorylation network regulates a plant potassium channel. Proceedings of the National Academy of Sciences, 104(40), 15959-15964. doi:10.1073/pnas.0707912104Sánchez-Barrena, M., Martínez-Ripoll, M., & Albert, A. (2013). Structural Biology of a Major Signaling Network that Regulates Plant Abiotic Stress: The CBL-CIPK Mediated Pathway. International Journal of Molecular Sciences, 14(3), 5734-5749. doi:10.3390/ijms14035734Quan, R., Lin, H., Mendoza, I., Zhang, Y., Cao, W., Yang, Y., … Guo, Y. (2007). SCABP8/CBL10, a Putative Calcium Sensor, Interacts with the Protein Kinase SOS2 to Protect Arabidopsis Shoots from Salt Stress. The Plant Cell, 19(4), 1415-1431. doi:10.1105/tpc.106.042291Ma, Y., Szostkiewicz, I., Korte, A., Moes, D., Yang, Y., Christmann, A., & Grill, E. (2009). Regulators of PP2C Phosphatase Activity Function as Abscisic Acid Sensors. Science. doi:10.1126/science.1172408Park, S.-Y., Fung, P., Nishimura, N., Jensen, D. R., Fujii, H., Zhao, Y., … Cutler, S. R. (2009). Abscisic Acid Inhibits Type 2C Protein Phosphatases via the PYR/PYL Family of START Proteins. Science. doi:10.1126/science.1173041Santiago, J., Rodrigues, A., Saez, A., Rubio, S., Antoni, R., Dupeux, F., … Rodriguez, P. L. (2009). Modulation of drought resistance by the abscisic acid receptor PYL5 through inhibition of clade A PP2Cs. The Plant Journal, 60(4), 575-588. doi:10.1111/j.1365-313x.2009.03981.xNishimura, N., Sarkeshik, A., Nito, K., Park, S.-Y., Wang, A., Carvalho, P. C., … Schroeder, J. I. (2009). PYR/PYL/RCAR family members are major in-vivo ABI1 protein phosphatase 2C-interacting proteins in Arabidopsis. The Plant Journal, 61(2), 290-299. doi:10.1111/j.1365-313x.2009.04054.xWang, P., Xue, L., Batelli, G., Lee, S., Hou, Y.-J., Van Oosten, M. J., … Zhu, J.-K. (2013). Quantitative phosphoproteomics identifies SnRK2 protein kinase substrates and reveals the effectors of abscisic acid action. Proceedings of the National Academy of Sciences, 110(27), 11205-11210. doi:10.1073/pnas.1308974110Umezawa, T., Sugiyama, N., Takahashi, F., Anderson, J. C., Ishihama, Y., Peck, S. C., & Shinozaki, K. (2013). Genetics and Phosphoproteomics Reveal a Protein Phosphorylation Network in the Abscisic Acid Signaling Pathway in Arabidopsis thaliana. Science Signaling, 6(270), rs8-rs8. doi:10.1126/scisignal.2003509Kollist, H., Nuhkat, M., & Roelfsema, M. R. G. (2014). Closing gaps: linking elements that control stomatal movement. New Phytologist, 203(1), 44-62. doi:10.1111/nph.12832Lind, C., Dreyer, I., López-Sanjurjo, E. J., von Meyer, K., Ishizaki, K., Kohchi, T., … Hedrich, R. (2015). Stomatal Guard Cells Co-opted an Ancient ABA-Dependent Desiccation Survival System to Regulate Stomatal Closure. Current Biology, 25(7), 928-935. doi:10.1016/j.cub.2015.01.067Geiger, D., Scherzer, S., Mumm, P., Stange, A., Marten, I., Bauer, H., … Hedrich, R. (2009). Activity of guard cell anion channel SLAC1 is controlled by drought-stress signaling kinase-phosphatase pair. Proceedings of the National Academy of Sciences, 106(50), 21425-21430. doi:10.1073/pnas.0912021106Imes, D., Mumm, P., Böhm, J., Al-Rasheid, K. A. S., Marten, I., Geiger, D., & Hedrich, R. (2013). Open stomata 1 (OST1) kinase controls R-type anion channel QUAC1 in Arabidopsis guard cells. The Plant Journal, 74(3), 372-382. doi:10.1111/tpj.12133Ishitani, M., Liu, J., Halfter, U., Kim, C.-S., Shi, W., & Zhu, J.-K. (2000). SOS3 Function in Plant Salt Tolerance Requires N-Myristoylation and Calcium Binding. The Plant Cell, 12(9), 1667-1677. doi:10.1105/tpc.12.9.1667Grefen, C., & Blatt, M. R. (2012). Do Calcineurin B-Like Proteins Interact Independently of the Serine Threonine Kinase CIPK23 with the K+ Channel AKT1? Lessons Learned from a Ménage à Trois. Plant Physiology, 159(3), 915-919. doi:10.1104/pp.112.198051Qiu, Q.-S., Guo, Y., Dietrich, M. A., Schumaker, K. S., & Zhu, J.-K. (2002). Regulation of SOS1, a plasma membrane Na+/H+ exchanger in Arabidopsis thaliana, by SOS2 and SOS3. Proceedings of the National Academy of Sciences, 99(12), 8436-8441. doi:10.1073/pnas.122224699Quintero, F. J., Martinez-Atienza, J., Villalta, I., Jiang, X., Kim, W.-Y., Ali, Z., … Pardo, J. M. (2011). Activation of the plasma membrane Na/H antiporter Salt-Overly-Sensitive 1 (SOS1) by phosphorylation of an auto-inhibitory C-terminal domain. Proceedings of the National Academy of Sciences, 108(6), 2611-2616. doi:10.1073/pnas.1018921108Núñez-Ramírez, R., Sánchez-Barrena, M. J., Villalta, I., Vega, J. F., Pardo, J. M., Quintero, F. J., … Albert, A. (2012). Structural Insights on the Plant Salt-Overly-Sensitive 1 (SOS1) Na+/H+ Antiporter. Journal of Molecular Biology, 424(5), 283-294. doi:10.1016/j.jmb.2012.09.015Ohta, M., Guo, Y., Halfter, U., & Zhu, J.-K. (2003). A novel domain in the protein kinase SOS2 mediates interaction with the protein phosphatase 2C ABI2. Proceedings of the National Academy of Sciences, 100(20), 11771-11776. doi:10.1073/pnas.2034853100Xu, J., Li, H.-D., Chen, L.-Q., Wang, Y., Liu, L.-L., He, L., & Wu, W.-H. (2006). A Protein Kinase, Interacting with Two Calcineurin B-like Proteins, Regulates K+ Transporter AKT1 in Arabidopsis. Cell, 125(7), 1347-1360. doi:10.1016/j.cell.2006.06.011Geiger, D., Scherzer, S., Mumm, P., Marten, I., Ache, P., Matschi, S., … Hedrich, R. (2010). Guard cell anion channel SLAC1 is regulated by CDPK protein kinases with distinct Ca2+affinities. Proceedings of the National Academy of Sciences, 107(17), 8023-8028. doi:10.1073/pnas.0912030107Brandt, B., Brodsky, D. E., Xue, S., Negi, J., Iba, K., Kangasjarvi, J., … Schroeder, J. I. (2012). Reconstitution of abscisic acid activation of SLAC1 anion channel by CPK6 and OST1 kinases and branched ABI1 PP2C phosphatase action. Proceedings of the National Academy of Sciences, 109(26), 10593-10598. doi:10.1073/pnas.1116590109Rodriguez, L., Gonzalez-Guzman, M., Diaz, M., Rodrigues, A., Izquierdo-Garcia, A. C., Peirats-Llobet, M., … Rodriguez, P. L. (2014). C2-Domain Abscisic Acid-Related Proteins Mediate the Interaction of PYR/PYL/RCAR Abscisic Acid Receptors with the Plasma Membrane and Regulate Abscisic Acid Sensitivity in Arabidopsis. The Plant Cell, 26(12), 4802-4820. doi:10.1105/tpc.114.129973Martens, S., & McMahon, H. T. (2008). Mechanisms of membrane fusion: disparate players and common principles. Nature Reviews Molecular Cell Biology, 9(7), 543-556. doi:10.1038/nrm2417Martens, S., Kozlov, M. M., & McMahon, H. T. (2007). How Synaptotagmin Promotes Membrane Fusion. Science, 316(5828), 1205-1208. doi:10.1126/science.1142614Jahn, R., Lang, T., & Südhof, T. C. (2003). Membrane Fusion. Cell, 112(4), 519-533. doi:10.1016/s0092-8674(03)00112-0Sutter, J.-U., Sieben, C., Hartel, A., Eisenach, C., Thiel, G., & Blatt, M. R. (2007). Abscisic Acid Triggers the Endocytosis of the Arabidopsis KAT1 K+ Channel and Its Recycling to the Plasma Membrane. Current Biology, 17(16), 1396-1402. doi:10.1016/j.cub.2007.07.020Bueso, E., Rodriguez, L., Lorenzo-Orts, L., Gonzalez-Guzman, M., Sayas, E., Muñoz-Bertomeu, J., … Rodriguez, P. L. (2014). The single-subunit RING-type E3 ubiquitin ligase RSL1 targets PYL4 and PYR1 ABA receptors in plasma membrane to modulate abscisic acid signaling. The Plant Journal, 80(6), 1057-1071. doi:10.1111/tpj.12708Larsen, J. B., Jensen, M. B., Bhatia, V. K., Pedersen, S. L., Bjørnholm, T., Iversen, L., … Stamou, D. (2015). Membrane curvature enables N-Ras lipid anchor sorting to liquid-ordered membrane phases. Nature Chemical Biology, 11(3), 192-194. doi:10.1038/nchembio.1733Demir, F., Horntrich, C., Blachutzik, J. O., Scherzer, S., Reinders, Y., Kierszniowska, S., … Kreuzer, I. (2013). Arabidopsis nanodomain-delimited ABA signaling pathway regulates the anion channel SLAH3. Proceedings of the National Academy of Sciences, 110(20), 8296-8301. doi:10.1073/pnas.1211667110Guerrero-Valero, M., Ferrer-Orta, C., Querol-Audi, J., Marin-Vicente, C., Fita, I., Gomez-Fernandez, J. C., … Corbalan-Garcia, S. (2009). Structural and mechanistic insights into the association of PKC -C2 domain to PtdIns(4,5)P2. Proceedings of the National Academy of Sciences, 106(16), 6603-6607. doi:10.1073/pnas.0813099106Guillen, J., Ferrer-Orta, C., Buxaderas, M., Perez-Sanchez, D., Guerrero-Valero, M., Luengo-Gil, G., … Corbalan-Garcia, S. (2013). Structural insights into the Ca2+ and PI(4,5)P2 binding modes of the C2 domains of rabphilin 3A and synaptotagmin 1. Proceedings of the National Academy of Sciences, 110(51), 20503-20508. doi:10.1073/pnas.1316179110Corbalan-Garcia, S., & Gómez-Fernández, J. C. (2014). Signaling through C2 domains: More than one lipid target. Biochimica et Biophysica Acta (BBA) - Biomembranes, 1838(6), 1536-1547. doi:10.1016/j.bbamem.2014.01.008CHO, W., & STAHELIN, R. (2006). Membrane binding and subcellular targeting of C2 domains. Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids, 1761(8), 838-849. doi:10.1016/j.bbalip.2006.06.014Verdaguer, N., Corbalan-Garcia, S., Ochoa, W. F., Fita, I., & Gómez-Fernández, J. C. (1999). Ca2+ bridges the C2 membrane-binding domain of protein kinase Cα directly to phosphatidylserine. The EMBO Journal, 18(22), 6329-6338. doi:10.1093/emboj/18.22.6329Honigmann, A., van den Bogaart, G., Iraheta, E., Risselada, H. J., Milovanovic, D., Mueller, V., … Jahn, R. (2013). Phosphatidylinositol 4,5-bisphosphate clusters act as molecular beacons for vesicle recruitment. Nature Structural & Molecular Biology, 20(6), 679-686. doi:10.1038/nsmb.2570Ausili, A., Corbalán-García, S., Gómez-Fernández, J. C., & Marsh, D. (2011). Membrane docking of the C2 domain from protein kinase Cα as seen by polarized ATR-IR. The role of PIP2. Biochimica et Biophysica Acta (BBA) - Biomembranes, 1808(3), 684-695. doi:10.1016/j.bbamem.2010.11.035Hermoso, J. A., Lagartera, L., González, A., Stelter, M., García, P., Martínez-Ripoll, M., … Menéndez, M. (2005). Insights into pneumococcal pathogenesis from the crystal structure of the modular teichoic acid phosphorylcholine esterase Pce. Nature Structural & Molecular Biology, 12(6), 533-538. doi:10.1038/nsmb940Thompson, D., Pepys, M. B., & Wood, S. P. (1999). The physiological structure of human C-reactive protein and its complex with phosphocholine. Structure, 7(2), 169-177. doi:10.1016/s0969-2126(99)80023-9Ochoa, W. F., Garcia-Garcia, J., Fita, I., Corbalan-Garcia, S., Verdaguer, N., & Gomez-Fernandez, J. C. (2001). Structure of the C2 domain from novel protein kinase Cϵ. A membrane binding model for Ca2+-independent C2 domains. Journal of Molecular Biology, 311(4), 837-849. doi:10.1006/jmbi.2001.4910Fuson, K., Rice, A., Mahling, R., Snow, A., Nayak, K., Shanbhogue, P., … Sutton, R. B. (2014). Alternate Splicing of Dysferlin C2A Confers Ca2+-Dependent and Ca2+-Independent Binding for Membrane Repair. Structure, 22(1), 104-115. doi:10.1016/j.str.2013.10.001Radhakrishnan, A., Stein, A., Jahn, R., & Fasshauer, D. (2009). The Ca2+Affinity of Synaptotagmin 1 Is Markedly Increased by a Specific Interaction of Its C2B Domain with Phosphatidylinositol 4,5-Bisphosphate. Journal of Biological Chemistry, 284(38), 25749-25760. doi:10.1074/jbc.m109.042499Schapire, A. L., Voigt, B., Jasik, J., Rosado, A., Lopez-Cobollo, R., Menzel, D., … Botella, M. A. (2008). Arabidopsis Synaptotagmin 1 Is Required for the Maintenance of Plasma Membrane Integrity and Cell Viability. The Plant Cell, 20(12), 3374-3388. doi:10.1105/tpc.108.063859Wang, J., Bello, O., Auclair, S. M., Wang, J., Coleman, J., Pincet, F., … Rothman, J. E. (2014). Calcium sensitive ring-like oligomers formed by synaptotagmin. Proceedings of the National Academy of Sciences, 111(38), 13966-13971. doi:10.1073/pnas.1415849111Jaenicke, R., & Rudolph, R. (1986). [12]Refolding and association of oligomeric proteins. Enzyme Structure Part L, 218-250. doi:10.1016/0076-6879(86)31043-7Goni, G. M., Epifano, C., Boskovic, J., Camacho-Artacho, M., Zhou, J., Bronowska, A., … Lietha, D. (2014). Phosphatidylinositol 4,5-bisphosphate triggers activation of focal adhesion kinase by inducing clustering and conformational changes. Proceedings of the National Academy of Sciences, 111(31), E3177-E3186. doi:10.1073/pnas.1317022111Wilkie, A. O. (1994). The molecular basis of genetic dominance. Journal of Medical Genetics, 31(2), 89-98. doi:10.1136/jmg.31.2.89Saez, A., Apostolova, N., Gonzalez-Guzman, M., Gonzalez-Garcia, M. P., Nicolas, C., Lorenzo, O., & Rodriguez, P. L. (2003). Gain-of-function and loss-of-function phenotypes of the protein phosphatase 2CHAB1reveal its role as a negative regulator of abscisic acid signalling. The Plant Journal, 37(3), 354-369. doi:10.1046/j.1365-313x.2003.01966.xSimons, K., & Gerl, M. J. (2010). Revitalizing membrane rafts: new tools and insights. Nature Reviews Molecular Cell Biology, 11(10), 688-699. doi:10.1038/nrm2977McMahon, H. T., & Boucrot, E. (2015). Membrane curvature at a glance. Journal of Cell Science, 128(6), 1065-1070. doi:10.1242/jcs.114454Tapken, W., & Murphy, A. S. (2015). Membrane nanodomains in plants: capturing form, function, and movement. Journal of Experimental Botany, 66(6), 1573-1586. doi:10.1093/jxb/erv054Lingwood, D., & Simons, K. (2007). Detergent resistance as a tool in membrane research. Nature Protocols, 2(9), 2159-2165. doi:10.1038/nprot.2007.294Schuck, P. (2000). Size-Distribution Analysis of Macromolecules by Sedimentation Velocity Ultracentrifugation and Lamm Equation Modeling. Biophysical Journal, 78(3), 1606-1619. doi:10.1016/s0006-3495(00)76713-0Bensmihen, S., To, A., Lambert, G., Kroj, T., Giraudat, J., & Parcy, F. (2004). Analysis of an activated ABI5 allele using a new selection method for transgenic Arabidopsis seeds. FEBS Letters, 561(1-3), 127-131. doi:10.1016/s0014-5793(04)00148-6Deblaere, R., Bytebier, B., De Greve, H., Deboeck, F., Schell, J., Van Montagu, M., & Leemans, J. (1985). Efficient octopine Ti plasmid-derived vectors forAgrobacterium-mediated gene transfer to plants. Nucleic Acids Research, 13(13), 4777-4788. doi:10.1093/nar/13.13.4777Clough, S. J., & Bent, A. F. (1998). Floral dip: a simplified method forAgrobacterium-mediated transformation ofArabidopsis thaliana. The Plant Journal, 16(6), 735-743. doi:10.1046/j.1365-313x.1998.00343.xHua, J. (2001). Plant growth homeostasis is controlled by the Arabidopsis BON1 and BAP1 genes. Genes & Development, 15(17), 2263-2272. doi:10.1101/gad.918101Kabsch, W. (2010). XDS. Acta Crystallographica Section D Biological Crystallography, 66(2), 125-132. doi:10.1107/s0907444909047337Winn, M. D., Ballard, C. C., Cowtan, K. D., Dodson, E. J., Emsley, P., Evans, P. R., … Wilson, K. S. (2011). Overview of theCCP4 suite and current developments. Acta Crystallographica Section D Biological Crystallography, 67(4), 235-242. doi:10.1107/s0907444910045749Adams, P. D., Afonine, P. V., Bunkóczi, G., Chen, V. B., Davis, I. W., Echols, N., … Zwart, P. H. (2010). PHENIX: a comprehensive Python-based system for macromolecular structure solution. Acta Crystallographica Section D Biological Crystallography, 66(2), 213-221. doi:10.1107/s0907444909052925Emsley, P., & Cowtan, K. (2004). Coot: model-building tools for molecular graphics. Acta Crystallographica Section D Biological Crystallography, 60(12), 2126-2132. doi:10.1107/s0907444904019158Dimasi, N., Flot, D., Dupeux, F., & Márquez, J. A. (2007). Expression, crystallization and X-ray data collection from microcrystals of the extracellular domain of the human inhibitory receptor expressed on myeloid cells IREM-1. Acta Crystallographica Section F Structural Biology and Crystallization Communications, 63(3), 204-208. doi:10.1107/s1744309107004903Emsley, P., Lohkamp, B., Scott, W. G., & Cowtan, K. (2010). Features and development ofCoot. Acta Crystallographica Section D Biological Crystallography, 66(4), 486-501. doi:10.1107/s0907444910007493DeLano (2002) The PyMOL Molecular Graphics System, 1.5.0.4 (DeLano Scientific, San Carlos, CA

21.6%-efficient monolithic perovskite/Cu(In,Ga)Se2 tandem solar cells with thin conformal hole transport layers for integration on rough bottom cell surfaces

Perovskite-based tandem solar cells can increase the power conversion efficiency (PCE) of conventional single-junction photovoltaic devices. Here, we present monolithic perovskite/CIGSe tandem solar cells with a perovskite top cell fabricated directly on an as-grown, rough CIGSe bottom cell. To prevent potential shunting due to the rough CIGSe surface, a thin NiOx layer is conformally deposited via atomic layer deposition on the front contact of the CIGSe bottom cell. The performance is further improved by an additional layer of the polymer PTAA at the NiOx/perovskite interface. This hole transport bilayer enables a 21.6% stabilized PCE of the tandem device at ∼0.8 cm2 active area. We use TEM/EDX measurements to investigate the deposition uniformity and conformality of the NiOx and PTAA layers. By absolute photoluminescence measurements, the contribution of the individual subcells to the tandem VOC is determined, revealing that further fine-tuning of the recombination layers might improve the tandem VOC. Finally, on the basis of the obtained results, we give guidelines to improve monolithic perovskite/CIGSe tandems toward predicted PCE estimates above 30%.BMBF, 03SF0540, Nachwuchsgruppe MeSa-Zuma: Entwicklung von spektral optimierten, hocheffizienten und langzeitstabilen Perowskit/Silizium Tandem SolarzellenBMWi, 0324095D, Verbundvorhaben: speedCIGS - Rechnerunterstützte Optimierung des CIGS-Depositionsprozesses in der industriellen Umsetzung; Teilvorhaben: Alkalibehandlung der CIGS Absorberoberfläche und monolithisch integrierte Tandem Zelle (p-TCM)BMWi, 0324076D, Verbundvorhaben: EFFCIS - Effizienzoptimierung von CIS-basierten Dünnschichtsolarzellen und -modulen; Teilvorhaben: Elektronenstrukturrechnungen zum Einfluss von Puffermaterialien auf die Eigenschaften des Cu(ln,Ga)(S,Se)2 Absorber

The Zoning of Semi-Enclosed Bodies of Water According to the Sediment Pollution: The Bay of Algeciras as a Case Example

This paper reports a study of the occurrence and levels of polycyclic aromatic hydrocarbons (PAHs) in a bay characterised by a chronic persistent impact. A total of 55 sediment samples were taken at different depths up to 111 m in two sampling campaigns. Chemical analyses were carried out by gas chromatography-mass spectroscopy. The results indicate that: (1) significant spatial variations exist, (2) levels of PAHs are related more strongly to the spatial distribution of sediments than to mineralogy/granulometry, (3) the sediments are slightly-to-moderately contaminated by PAHs, and (4) these PAHs derive from pyrolytic and petrogenic sources. Through use of an innovative data classification system (proposed according to depth and spatial location of sampling points), and using factorial and cluster techniques, five zones have been differentiated depending on the contamination level and source