Trade Credit, Collateral Liquidation and Borrowing Constraints

The paper proposes a model of collateralized bank and trade credit. Firms use a two-input technology. Assuming that the supplier is better able to extract value from existing assets and has an information advantage over other creditors, the paper derives a series of predictions. (1) Financially unconstrained firms (with unused bank credit lines) take trade credit for a liquidation motive. (2) The reliance on trade credit does not depend on credit rationing, if inputs are liquid enough. (3) Firms buying goods make more purchases on account than those buying services, while suppliers of services offer more trade credit than those of standardized goods. (4) Suppliers lend inputs to their customers but not cash. (5) Greater reliance on trade credit is associated with more intensive use of tangible inputs. (6) Better creditor protection decreases both the use of trade credit and input tangibility.trade credit, collateral, financial constraints, asset tangibility, creditor protection ibility

Trade credit, collateral liquidation, and borrowing constraints

Assuming that firms' suppliers are better able to extract value from the liquidation of assets in default and have an information advantage over other creditors, the paper derives six predictions on the use of trade credit. (1) Financially unconstrained firms (with unused bank credit lines) take trade credit to exploit the supplier's liquidation advantage. (2) If inputs purchased on account are sufficiently liquid, the reliance on trade credit does not depend on credit rationing. (3) Firms buying goods make more purchases on account than those buying services, while suppliers of services offer more trade credit than those of standardized goods. (4) Suppliers lend inputs to their customers but not cash. (5) Greater reliance on trade credit is associated with more intensive use of tangible inputs. (6) Better creditor protection decreases both the use of trade credit and input tangibility

Materie prime di origine naturale nel processo di geopolimerizzazione

Geopolymers are inorganic materials prepared via a room temperature treatment (25-120?C) with alkali activation. The main applications of these materials is in the field of building materials, recycle and inertization of waste, restoration. The production and final product is optimised by a careful selection of starting materials, i.e. aluminosilicate powders. In this paper are presented aluminosilicates from natural source, as an example kaolin, clays or volcanic ash. Metakaolin is the most reactive due to its amorphous structure and aluminium coordination; its reactivity is also influenced by its mineralogical origin, morphology of grains, and calcinations method. Volcanic ash present lower reactivity and the better consolidation temperature to obtain mechanically strong materials appears to be around 400?CI materiali geopolimerici sono materiali inorganici ottenuti con consolidamento a bassa temperatura (25-120?C) mediante una reazione chimica in ambiente alcalino. Sono utilizzati per applicazioni ad alta temperatura e strutturali in edilizia, per il riciclo e /o l?inertizzazione di scorie industriali, per il restauro. L?opportuna selezione di materie prime alluminosilicatiche ? alla base dell?ottimizzazione del ciclo produttivo e del prodotto finale. Vengono presentate materie prime di origine naturale, quali il metacaolino, derivato dalla calcinazione del caolino, e le ceneri vulcaniche. Il metacaolino ? la materia prima pi? reattiva grazie alla struttura amorfa e alla coordinazione dell?alluminio: sulla reattivit? influiscono sia la morfologia e le caratteristiche del caolino di origine, sia la metodologia di calcinazione. Le ceneri vulcaniche hanno una minore reattivit? che pu? esser ovviata tramite un consolidamento a circa 400?C portando a prodotti geopolimerici con buone prestazioni meccanich

Two separate pathways underlie NADH and succinate oxidation in swine heart mitochondria: Kinetic evidence on the mobile electron carriers

: We have investigated NADH and succinate aerobic oxidation in frozen and thawed swine heart mitochondria. Simultaneous oxidation of NADH and succinate showed complete additivity under a variety of experimental conditions, suggesting that the electron fluxes originating from NADH and succinate are completely independent and do not mix at the level of the so-called mobile diffusible components. We ascribe the results to mixing of the fluxes at the level of cytochrome c in bovine mitochondria: the Complex IV flux control coefficient in NADH oxidation was high in swine mitochondria but very low in bovine mitochondria, suggesting a stronger interaction of cytochrome c with the supercomplex in the former. This was not the case in succinate oxidation, in which Complex IV exerted little control also in swine mitochondria. We interpret the data in swine mitochondria as restriction of the NADH flux by channelling within the I-III2-IV supercomplex, whereas the flux from succinate shows pool mixing for both Coenzyme Q and probably cytochrome c. The difference between the two types of mitochondria may be ascribed to different lipid composition affecting the cytochrome c binding properties, as suggested by breaks in Arrhenius plots of Complex IV activity occurring at higher temperatures in bovine mitochondria

Sulfide affects the mitochondrial respiration, the Ca2+-activated F1FO-ATPase activity and the permeability transition pore but does not change the Mg2+-activated F1FO-ATPase activity in swine heart mitochondria

In mammalian cells enzymatic and non-enzymatic pathways produce H2S, a gaseous transmitter which recently emerged as promising therapeutic agent and modulator of mitochondrial bioenergetics. To explore this topic, the H2S donor NaHS, at micromolar concentrations, was tested on swine heart mitochondria. NaHS did not affect the F1FO-ATPase activated by the natural cofactor Mg2, but, when Mg2+ was replaced by Ca2+, a slight 15% enzyme inhibition at 100M NaHS was shown. Conversely, both the NADH-O2 and succinate-O2 oxidoreductase activities were totally inhibited by 200muM NaHS with IC50 values of 61.6±4.1 and 16.5±4.6muM NaHS, respectively. Since the mitochondrial respiration was equally inhibited by NaHS at both first or second respiratory substrates sites, the H2S generation may prevent the electron transfer from complexes I and II to downhill respiratory chain complexes, probably because H2S competes with O2 in complex IV, thus reducing membrane potential as a consequence of the cytochrome c oxidase activity inhibition. The Complex IV blockage by H2S was consistent with the linear concentration-dependent NADH-O2 oxidoreductase inhibition and exponential succinate-O2 oxidoreductase inhibition by NaHS, whereas the coupling between substrate oxidation and phosphorylation was unaffected by NaHS. Even if H2S is known to cause sulfhydration of cysteine residues, thiol oxidizing (GSSG) or reducing (DTE) agents, did not affect the F1FO-ATPase activities and mitochondrial respiration, thus ruling out any involvement of post-translational modifications of thiols. The permeability transition pore, the lethal channel which forms when the F1FO-ATPase is stimulated by Ca2+, did not open in the presence of NaHS, which showed a similar effect to ruthenium red, thus suggesting a putative Ca2+ transport cycle inhibition

Modelling soil water conent in a tomato field: proximal gamma ray spectroscopy and soil-crop system models

Proximal soil sensors are taking hold in the understanding of soil hydrogeological processes involved in precision agriculture. In this context, permanently installed gamma ray spectroscopy stations represent one of the best space-time trade off methods at field scale. This study proved the feasibility and reliability of soil water content monitoring through a seven-month continuous acquisition of terrestrial gamma radiation in a tomato test field. By employing a 1 L sodium iodide detector placed at a height of 2.25 m, we investigated the gamma signal coming from an area having a ~25 m radius and from a depth of approximately 30 cm. Experimental values, inferred after a calibration measurement and corrected for the presence of biomass, were corroborated with gravimetric data acquired under different soil moisture conditions, giving an average absolute discrepancy of about 2%. A quantitative comparison was carried out with data simulated by AquaCrop, CRITeRIA, and IRRINET soil-crop system models. The different goodness of fit obtained in bare soil condition and during the vegetated period highlighted that CRITeRIA showed the best agreement with the experimental data over the entire data-taking period while, in presence of the tomato crop, IRRINET provided the best results.Comment: 18 pages, 9 Figures, 3 Table

BCL11A mRNA targeting by miR-210: A possible network regulating γ-globin gene expression

The involvement of microRNAs in the control of repressors of human g-globin gene transcription has been firmly demonstrated, as described for the miR-486-3p mediated down-regulation of BCL11A. On the other hand, we have reported that miR-210 is involved in erythroid differentiation and, possibly, in γ-globin gene up-regulation. In the present study, we have identified the coding sequence of BCL11A as a possible target of miR-210. The following results sustain this hypothesis: (a) interactions between miR-210 and the miR-210 BCL11A site were demonstrated by SPR-based biomolecular interaction analysis (BIA); (b) the miR-210 site of BCL11A is conserved through molecular evolution; (c) forced expression of miR-210 leads to decrease of BCL11A-XL and increase of γ-globin mRNA content in erythroid cells, including erythroid precursors isolated from β-thalassemia patients. Our study suggests that the coding mRNA sequence of BCL11A can be targeted by miR-210. In addition to the theoretical point of view, these data are of interest from the applied point of view, supporting a novel strategy to inhibit BCL11A by mimicking miR-210 functions, accordingly with the concept supported by several papers and patent applications that inhibition of BCL11A is an efficient strategy for fetal hemoglobin induction in the treatment of β-thalassemia

Newsletter Serit n. 9 - Marzo 2014

La IVa Giornata Nazionale della Piattaforma Serit è stata dedicata ad esempi di “best practice” di progetti di ricerca, finanziati dal programma quadro FP7-Security Research Project, che si sono dimostrati “end-users friendly”. Il numero di questa newsletter offre una breve sintesi della giornata