Evaluation contingente d’aménités paysagères liées à un espace vert urbain. Une application au cas du Parc Balzac de la ville d’Angers

Cet article propose une évaluation contingente des services esthétiques et récréatifs rendus par un parc urbain. Les dispositions à payer d’un échantillon d’usagers d’un parc urbain dans la ville d’Angers (le parc Balzac) ont été révélées sur la base de deux scénarios reflétant des changements d’attributs paysagers. Les attributs retenus correspondent au degré d’ouverture et à l’effort de fleurissement. Lesupport de paiement proposé repose sur une carte de paiement retraçant les augmentations de la taxe d’habitation à prévoir. Nous avons évalué les facteurs qui augmentent la probabilité de donner une disposition à payer positive. Nos résultats montrent que les aménités paysagères recherchées par les visiteurs de deux scénarios du parc Balzac diffèrent. Dans le premier scénario, seul l’usage lié à une activité de loisirs est exprimé, tandis que dans le second, une appréciation esthétique des aménités est également envisagée

Pulse-like and crack-like ruptures in experiments mimicking crustal earthquakes

Theoretical studies have shown that the issue of rupture modes has important implications for fault constitutive laws, stress conditions on faults, energy partition and heat generation during earthquakes, scaling laws, and spatiotemporal complexity of fault slip. Early theoretical models treated earthquakes as crack-like ruptures, but seismic inversions indicate that earthquake ruptures may propagate in a self-healing pulse-like mode. A number of explanations for the existence of slip pulses have been proposed and continue to be vigorously debated. This study presents experimental observations of spontaneous pulse-like ruptures in a homogeneous linear-elastic setting that mimics crustal earthquakes; reveals how different rupture modes are selected based on the level of fault prestress; demonstrates that both rupture modes can transition to supershear speeds; and advocates, based on comparison with theoretical studies, the importance of velocity-weakening friction for earthquake dynamics

The continuity of the inversion and the structure of maximal subgroups in countably compact topological semigroups

In this paper we search for conditions on a countably compact (pseudo-compact) topological semigroup under which: (i) each maximal subgroup $H(e)$ in $S$ is a (closed) topological subgroup in $S$; (ii) the Clifford part $H(S)$(i.e. the union of all maximal subgroups) of the semigroup $S$ is a closed subset in $S$; (iii) the inversion $\operatorname{inv}\colon H(S)\to H(S)$ is continuous; and (iv) the projection $\pi\colon H(S)\to E(S)$, $\pi\colon x\longmapsto xx^{-1}$, onto the subset of idempotents $E(S)$ of $S$, is continuous

Bis(2,3,5,6-tetra-2-pyridylpyrazine-κ3 N 2,N 1,N 6)iron(II) bis­(dicyanamidate) 4.5-hydrate

In the title compound, [Fe(C24H16N6)2][N(CN)2]2·4.5H2O, the central iron(II) ion is hexa­coordinated by six N atoms of two tridentate 2,3,5,6-tetra-2-pyridylpyrazine (tppz) ligands. Two dicyanamide anions [dca or N(CN)2 −] act as counter-ions, and 4.5 water mol­ecules act as solvation agents. The structure contains isolated cationic iron(II)–tppz complexes and the final neutrality is obtained with the two dicyanamide anions. One of the dicyanamide anions and a water mol­ecule are disordered with an occupancy ratio of 0.614 (8):0.386 (8). O—H⋯O, O—H⋯N and C—H⋯O hydrogen bonds involving dca, water and tppz mol­ecules are observed

MORPHOLOGICAL CHANGES IN WISTAR RAT FETUSES FROM PROGENITORS WITH SUCROSE-INDUCED METABOLIC SYNDROME

Women exhibiting the components of metabolic syndrome before the pregnancy have a high risk of fetal placental dysfunction, even fetal death. Moreover, glucotoxicity has been linked to birth defects. These issues have motivated checking the possible association between a metabolic syndrome and morphological damages in the conception product. In this paper, morphological alterations produced on the fetus by the metabolic syndrome of progenitors were determined in an experimental model. The bio-model was developed in Wistar rats by supplying them with 35 % sucrose from the intrauterine stage up to eighteen weeks of age. Subsequently, the crossing was performed, the pregnancy was confirmed, and blood pressure was checked. Two groups of pregnancy were formed; metabolic syndrome and healthy control. Cesarean section was performed on day twenty of gestation, in order to make the corresponding first segment studies of reproductive toxicity. Maternal parameters such as body and organ weight were assessed. Weight, crown-rump length, and the total number of fetuses by group, as well as the skeletal and soft tissue of the fetuses were recorded. The hematoma was the main external change found, as well as there was a significant decrease in fetuses’ weight of metabolic syndrome parents’ group. In these fetuses, the absence of Xiphoid and Sterne brae was reported as the principal developmental delays in bone tissue and no noticeable damage was observed in a soft one. These results suggest that metabolic syndrome morphologically affects the conception product

Dynamical system analysis and forecasting of deformation produced by an earthquake fault

We present a method of constructing low-dimensional nonlinear models describing the main dynamical features of a discrete 2D cellular fault zone, with many degrees of freedom, embedded in a 3D elastic solid. A given fault system is characterized by a set of parameters that describe the dynamics, rheology, property disorder, and fault geometry. Depending on the location in the system parameter space we show that the coarse dynamics of the fault can be confined to an attractor whose dimension is significantly smaller than the space in which the dynamics takes place. Our strategy of system reduction is to search for a few coherent structures that dominate the dynamics and to capture the interaction between these coherent structures. The identification of the basic interacting structures is obtained by applying the Proper Orthogonal Decomposition (POD) to the surface deformations fields that accompany strike-slip faulting accumulated over equal time intervals. We use a feed-forward artificial neural network (ANN) architecture for the identification of the system dynamics projected onto the subspace (model space) spanned by the most energetic coherent structures. The ANN is trained using a standard back-propagation algorithm to predict (map) the values of the observed model state at a future time given the observed model state at the present time. This ANN provides an approximate, large scale, dynamical model for the fault.Comment: 30 pages, 12 figure

Deciphering the Non-Equivalence of Serine and Threonine O-Glycosylation Points: Implications for Molecular Recognition of the Tn Antigen by an anti-MUC1 Antibody

© 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. The structural features of MUC1-like glycopeptides bearing the Tn antigen (α-O-GalNAc-Ser/Thr) in complex with an anti MUC-1 antibody are reported at atomic resolution. For the α-O-GalNAc-Ser derivative, the glycosidic linkage adopts a high-energy conformation, barely populated in the free state. This unusual structure (also observed in an α-S-GalNAc-Cys mimic) is stabilized by hydrogen bonds between the peptidic fragment and the sugar. The selection of a particular peptide structure by the antibody is thus propagated to the carbohydrate through carbohydrate/peptide contacts, which force a change in the orientation of the sugar moiety. This seems to be unfeasible in the α-O-GalNAc-Thr glycopeptide owing to the more limited flexibility of the side chain imposed by the methyl group. Our data demonstrate the non-equivalence of Ser and Thr O-glycosylation points in molecular recognition processes. These features provide insight into the occurrence in nature of the APDTRP epitope for anti-MUC1 antibodies.Peer Reviewe

Possible relationship between Seismic Electric Signals (SES) lead time and earthquake stress drop

Stress drop values for fourteen large earthquakes with MW ≥ 5.4 which occurred in Greece during the period 1983–2007 are available. All these earthquakes were preceded by Seismic Electric Signals (SES). An attempt has been made to investigate possible correlation between their stress drop values and the corresponding SES lead times. For the stress drop, we considered the Brune stress drop, ΔσB, estimated from far field body wave displacement source spectra and ΔσSB derived from the strong motion acceleration response spectra. The results show a relation may exist between Brune stress drop, ΔσB, and lead time which implies that earthquakes with higher stress drop values are preceded by SES with shorter lead time

Evaluaci?n de la competitividad de fuentes energ?ticas para la cocci?n, calefacci?n y calentamiento de agua en zonas urbanas y rurales de Arequipa

Arequipa tiene un porcentaje de cobertura el?ctrica de 91.41% y la distribuidora 98.23% dentro de su zona de concesi?n, lo que evidencia a?n una brecha por cubrir para garantizar el acceso de los ciudadanos a la energ?a. El objetivo general de este trabajo es: Contribuir al acceso a la energ?a en la Regi?n Arequipa; y como objetivos espec?ficos: (i) Determinar el energ?tico con el menor costo para la atenci?n de necesidades b?sicas como cocci?n, calefacci?n y calentamiento de agua en zonas urbanas y rurales de la Regi?n Arequipa, considerando variables: distancia, temperatura y densidad poblacional. (ii) Establecer un modelo matem?tico que determine el energ?tico m?s eficiente para cocci?n, calefacci?n y calentamiento de agua en la Regi?n Arequipa, que pueda ser replicable en otras zonas. Se ha evaluado dentro de la zona de concesi?n de la empresa de distribuci?n el?ctrica, la competitividad de las siguientes fuentes energ?ticas: (i) Electricidad; (ii) GLP; (iii) SFV; (iv) GN, para cocci?n de alimentos, calentamiento de agua y calefacci?n, considerando como variables: Distancia, temperatura y densidad poblacional. Las conclusiones indican: (i) Que el energ?tico m?s eficiente para la cocci?n de alimentos, calentamiento de agua y calefacci?n, es la electricidad, seguido del del GLP, SFV y finalmente el gas natural; (ii) Para que la distribuci?n de gas natural sea competitiva se requiere demanda industrial y comercial, adicionalmente a la demanda domiciliaria; ya que sin estas no se alcanza a cubrir los costos de inversi?n de acuerdo a la tasa de 12% y al per?odo de 30 a?os para el retorno de esta; (iii) Para el acceso de energ?a, la electricidad necesita menos subsidio que el gas natural por tanto no se ver?an afectados el FISE y FOSE