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The i-motif is a DNA structure formed by cytosine-rich sequences, very relevant from a biochemical point of view and potentially useful in nanotechnology as pH-sensitive nanodevices or nanomotors. To provide a different view on the structural changes and dynamics of direct excitation processes involving i-motif structures, the use of rapid-scan FTIR spectroscopy is proposed. Hybrid hard- and soft-modelling based on the Multivariate Curve Resolution by Alternating Least Squares (MCR-ALS) algorithm has been used for the resolution of rapid-scan FTIR spectra and the interpretation of the photochemically induced time-dependent conformational changes of i-motif structures. The hybrid hard- and soft-modelling version of MCR-ALS (HS-MCR), which allows the introduction of kinetic models to describe process behavior, provides also rate constants associated with the transitions modeled. The results show that UV irradiation does not produce degradation of the studied sequences but induces the formation of photodimers. The presence of these affect much more the stability of i-motif structures formed by short sequences than that of those formed by longer sequences containing additional structural stabilizing elements, such as hairpins. ; Sanae Benabou thanks the LAboratoire de Spectrochimie Infrarouge et Raman (LASIR) for all the support, especially, Dr. Isabelle Waele for her help in the acquisition of rapid-scan FTIR measurements. Funding from Spanish government (CTQ2017-84415-R and CTQ2015-66254-C2-2-P) and recognition from the Autonomous Catalan government (2017SGR753 and 2017SGR114) are acknowledged. ; Peer reviewed

This research has been supported by the Dutch Science Organization (NWO (grant no. 818.02.019)), the Deutsche Forschungsgemeinschaft (grant nos. MA 497/2-1 and MA 497/11-1), the Alexander von Humboldt-Stiftung, and the People Programme (Marie Curie Actions) of the European Union, Seventh Framework Programme (grant agreement no. 252213). ; The electron donor in photosystem I (PSI), the chlorophyll dimer P700, is studied by photochemically induced dynamic nuclear polarization (photo-CIDNP) magic angle spinning (MAS) nuclear magnetic resonance (NMR) on selectively 13C and uniformly 15N labeled PSI core preparations (PSI-100) obtained from the aquatic plant duckweed (Spirodela oligorrhiza). Light-induced signals originate from the isotope-labeled nuclei of the cofactors involved in the spin-correlated radical pair forming upon light excitation. Signals are assigned to the two donor cofactors (Chl a and Chl a') and the two acceptor cofactors (both Chl a). Light-induced signals originating from both donor and acceptor cofactors demonstrate that electron transfer occurs through both branches of cofactors in the pseudo-C2 symmetric reaction center (RC). The experimental results supported by quantum chemical calculations indicate that this functional symmetry occurs in PSI despite similarly sized chemical shift differences between the cofactors of PSI and the functionally asymmetric special pair donor of the bacterial RC of Rhodobacter sphaeroides. This contributes to converging evidence that local differences in time-averaged electronic ground-state properties, over the donor are of little importance for the functional symmetry breaking across photosynthetic RC species. ; Publisher PDF ; Peer reviewed

1 Introduction -- 2 Acids, bases, and the nature of the hydrogen ion -- 3 The investigation of protolytic equilibria in aqueous solution -- 4 The effect of the solvent on protolytic equilibria -- 5 The thermodynamics of protolytic equilibria -- 6 Acid-base strength and molecular structure -- 7 The direct study of rates of simple proton-transfer reactions -- 8 The indirect study of rates of proton transfer -- 9 Examples of reactions catalysed by acids and bases -- 10 Rates, equilibria, and structures in proton-transfer reactions -- 11 Isotope effects in proton-transfer equilibria -- 12 Kinetic isotope effects in proton-transfer reactions -- Author Index.

In this paper, we set up a three-period stochastic overlapping generations model to analyze the implications of income inequality and mobility for demand for redistribution and social insurance. We model the size of two different public programs under the welfare state. We investigate bidimensional voting on the tax rates that determine the allocation of government revenues among transfer payments and old-age pensions. We show that the coalitions formed, the resulting political equilibria, and the demand for redistribution crucially depend on the level of income inequality and mobility.

Abstract
Interest groups exert influence on legislators' decisions about how to organize the contracting process in public procurement. Traditionally, centralized contracting structures have been favored to avoid allocative inefficiency. However, legislators have recently started to allow more and more contract delegation in public procurement projects. Different interest groups argue in favor and against this tendency. The objective of this paper is to judge from a normative perspective what socially efficient contracting structures are and from a positive perspective what contracting structure we can expect to find as equilibria of an endogenous lobby formation game. From the normative perspective, it is shown that both contracting structures can be socially efficient. Furthermore, the conditions under which a certain contracting structure is socially superior are identified. From the positive perspective the main result shows that we can have equilibria of the lobby formation game with socially efficient contracting structures and with socially inefficient contracting structures. Again, the circumstances under which the different equilibria occur are identified.

This paper presents a market with asymmetric information where a privately revealing equilibrium obtains in a competitive framework and where incentives to acquire information are preserved. The equilibrium is efficient, and the paradoxes associated with fully revealing rational expectations equilibria are precluded without resorting to noise traders. The model admits a reinterpretation in which behavioral traders coexist with rational traders, and it allows us to characterize the amount of induced mispricing.

Background: Drug-induced liver injury (DILI) is an adverse reaction caused by the intake of drugs of common use that produces liver damage. The impact of DILI is estimated to affect around 20 in 100,000 inhabitants worldwide each year. Despite being one of the main causes of liver failure, the pathophysiology and mechanisms of DILI are poorly understood. In the present study, we developed an ensemble learning approach based on different features (CMap gene expression, chemical structures, drug targets) to predict drugs that might cause DILI and gain a better understanding of the mechanisms linked to the adverse reaction. Results: We searched for gene signatures in CMap gene expression data by using two approaches: phenotype-gene associations data from DisGeNET, and a non-parametric test comparing gene expression of DILI-Concern and No-DILI-Concern drugs (as per DILIrank definitions). The average accuracy of the classifiers in both approaches was 69%. We used chemical structures as features, obtaining an accuracy of 65%. The combination of both types of features produced an accuracy around 63%, but improved the independent hold-out test up to 67%. The use of drug-target associations as feature obtained the best accuracy (70%) in the independent hold-out test. Conclusions: When using CMap gene expression data, searching for a specific gene signature among the landmark genes improves the quality of the classifiers, but it is still limited by the intrinsic noise of the dataset. When using chemical structures as a feature, the structural diversity of the known DILI-causing drugs hampers the prediction, which is a similar problem as for the use of gene expression information. The combination of both features did not improve the quality of the classifiers but increased the robustness as shown on independent hold-out tests. The use of drug-target associations as feature improved the prediction, specially the specificity, and the results were comparable to previous research studies. ; The authors received funding from the Innovative Medicines Initiative 2 Joint Undertaking under grant agreements TransQST and eTRANSAFE (refs: 116030, 777365). This Joint Undertaking receives support from the European Union's Horizon 2020 research and innovation programme and EFPIA companies in kind contribution. The authors also received support from Spanish Ministry of Economy (MINECO, refs: BIO2017–85329-R (FEDER, EU), RYC-2015-17519) as well as EU H2020 Programme 2014–2020 under grant agreement No. 676559 (Elixir-Excelerate) and from Agència de Gestió D'ajuts Universitaris i de Recerca Generalitat de Catalunya (AGAUR, ref.: 2017SGR01020). L.I.F. received support from ISCIII-FEDER (ref: CPII16/00026). The Research Programme on Biomedical Informatics (GRIB) is a member of the Spanish National Bioinformatics Institute (INB), PRB2-ISCIII and is supported by grant PT13/0001/0023, of the PE I + D + i 2013–2016, funded by ISCIII and FEDER. The DCEXS is a "Unidad de Excelencia María de Maeztu", funded by the MINECO (ref: MDM-2014-0370). J.A.P. received support from the CAMDA Travel Fellowship.

Bonds Transaction Services and the Term Structure of Interest Rates: Implications for Equilibrium Determinacy Abstract: We introduce two bonds in a standard New-Keynesian model to study the role of segmentation in bond markets for the determinacy of rational expectations equilibria. We use a strongly-separable utility function to model short-term bonds providing transaction services for the purchase of consumption goods. Long-term bonds, instead, provide the standard services of store of value. We obtain a fully analytical solution for the bond pricing kernel, allowing to endogenize the term spread within the model. In this way, we study equilibrium determinacy properties within a context embedding the full information derived from term structure of interest rates. Our results show that, when utility is weakly separable between consumption and bonds, the Taylor principle holds only conditional to a non-linear relation between output and inflation targeting coefficients of monetary policy rule. Achieving solution determinacy requires to constraint policy coefficients to lie within bounds depending on structural parameters of the model. This paper provides an analytical setting useful for several generalizations to address the stability properties in dynamic models including the term structure of interest rates, induced by policy rules.

In this paper, we study a two-period pure exchange economy with idiosyncratic uncertainty, moral hazard and multiple consumption goods. We consider two different market structures: contingent commodity markets on the one hand, and financial plus spot commodity markets on the other hand. We propose a competitive equilibrium concept for each market structure. We first verify that it is possible to decentralize constrained efficient allocations as equilibria with contingent markets. Subsequently, we characterize the conditions which prevent constrained efficient allocations from being decentralized as equilibria with financial markets.

The joint evolution of participating and complying firms in a public VA, along with the evolution of the pollution stock is examined. Replicator dynamics modeling participation and compliance are combined with pollution stock dynamics. Fast-slow selection dynamics are used to capture the fact that decisions to participate in and further comply with the public VA evolve in different time scales. Evolutionary stable (ES) equilibria depend on the structure of the legislation and auditing probability. Partial participation and partial compliance can be ES equilibria, with possible multiplicities, in addition to the monomorphic equilibria of full (non) compliance. Convergence to these equilibria could be monotonic or oscillating. Full participation and compliance can be attained if the regulator is pre-committed to certain legislation and inspection probabilities, or by appropriate choices of the legislatively set emission level and the non-compliance fine.

14 pages, 6 figures, 4 tables.-- This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited ; Harvest mortality typically truncates the harvested species' size structure, thereby reducing phenotypic complexity, which can lead to reduced population productivity, increased population variability, and selection on an array of life history traits that can further alter these demographic processes. Marine protected areas (MPAs) are a potential tool to protect older, larger individuals and therefore mitigate such ecological and evolutionary effects of harvest, depending on the degree of connectivity among areas. Such MPA protection relies on a shift in size-dependent mortality, the measurement of which can therefore serve as an early indicator of whether MPAs might achieve the desired longer-term ecological and evolutionary responses. We directly measured MPA effects on size-selective mortality and associated size structure using mark–recapture data on European lobster (Homarus gammarus) collected at three MPA–control area pairs in southern Norway during one decade (n = 5,943). Mark–recapture modeling, accounting for variation in recapture probabilities, revealed (1) that annual mean survival was higher inside MPAs (0.592) vs. control areas (0.298) and (2) that significant negative relationships between survival and body size occurred at the control areas but not in the MPAs, where the effect of body size was predominantly positive. Additionally, we found (3) that mean and maximum body size increased over time inside MPAs but not in control areas. Overall, our results suggest that MPAs can rebuild phenotypic complexity (i.e., size structure) and provide protection from harvest selection ; Tagging of lobsters and fieldwork was supported by the Institute of Marine Research through long term funding for MPA monitoring in Skagerrak. Manuscript preparation was funded by the Research Council of Norway (RCN), project 201917 (PROMAR) and 294926 (CODSIZE), and by MINECO (Spanish Government) through a Juan de la Cierva Grant (ref. FJCI- 2014-22482) to A. Fern andez-Chac on. Collaboration between authors from University of Agder and UC Berkeley was made possible through a grant from Peder Sather Center for Advanced Study at UC Berkeley. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 793627 (BEMAR). ; Peer reviewed

This article shows that social norms are better explained as correlating devices for a correlated equilibrium of the underlying stage game, rather than Nash equilibria. Whereas the epistemological requirements for rational agents playing Nash equilibria are very stringent and usually implausible, the requirements for a correlated equilibrium amount to the existence of common priors, which we interpret as induced by the cultural system of the society in question. When the correlating device has perfect information, we need in addition only to posit that individuals obey the social norm when it is costless to do so. When the correlating device has incomplete information, the operation of the social norm requires that individuals have a predisposition to follow the norm even when this is costly. The latter case explains why social norms are associated with other-regarding preferences and provides a basis for analyzing honesty and corruption.

We show that Ergin & Sönmez's (2006) results which show that for schools it is a dominant strategy to truthfully rank the students under the Boston mechanism, and that the Nash equilibrium outcomes in undominated strategies of the induced game are stable, rely crucially on two assumptions. First, (a) that schools need to be restricted to find all students acceptable, and (b) that students cannot observe the priorities set by the schools before submitting their preferences. We show that relaxing either assumption eliminates the strategy dominance, and that Nash equilibrium outcomes in undominated strategies for the simultaneous induced game in case (a) and subgame perfect Nash equilibria in case (b) may contain unstable matchings. We also show that when able to manipulate capacities, schools may only have an incentive to do so if students submit their preferences after observing the reported capacities.

Sun-Induced fluorescence at 760 nm (F760) is increasingly being used to predict gross primary production (GPP) through light use efficiency (LUE) modeling, even though the mechanistic processes that link the two are not well understood. We analyzed the effect of nitrogen (N) and phosphorous (P) availability on the processes that link GPP and F760 in a Mediterranean grassland manipulated with nutrient addition. To do so, we used a combination of process-based modeling with Soil-Canopy Observation of Photosynthesis and Energy (SCOPE), and statistical analyses such as path modeling. With this study, we uncover the mechanisms that link the fertilization-driven changes in canopy nitrogen concentration (N%) to the observed changes in F760 and GPP. N addition changed plant community structure and increased canopy chlorophyll content, which jointly led to changes in photosynthetic active radiation (APAR), ultimately affecting both GPP and F760. Changes in the abundance of graminoids, (%graminoids) driven by N addition led to changes in structural properties of the canopy such as leaf angle distribution, that ultimately influenced observed F760 by controlling the escape probability of F760 (Fesc). In particular, we found a change in GPP¿F760 relationship between the first and the second year of the experiment that was largely driven by the effect of plant type composition on Fesc, whose best predictor is %graminoids. The P addition led to a statistically significant increase on light use efficiency of fluorescence emission (LUEf), in particular in plots also with N addition, consistent with leaf level studies. The N addition induced changes in the biophysical properties of the canopy that led to a trade-off between surface temperature (Ts), which decreased, and F760 at leaf scale (F760leaf,fw), which increased. We found that Ts is an important predictor of the light use efficiency of photosynthesis, indicating the importance of Ts in LUE modeling approaches to predict GPP ; The project received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 721995. The authors acknowledge the Alexander von Humboldt Foundation for supporting this research with the Max-Planck Prize to Markus Reichstein, and the EUFAR TA project DEHESHyrE (EU FP7 Program), the EnMAP project "MoReDEHESHyReS" (Contract No. 50EE1621, German Aerospace Center (DLR) and German Federal Ministry of Economic Affairs and Energy), SynerTGE (CGL2015-69095-R, MINECO/FEDER, UE) and FLUχPEC (CGL2012-34383, Spanish Ministry of Economy and Competitiveness). This work was supported by a research grant (18968) from VILLUM FONDEN