Anomalous Roughening in Experiments of Interfaces in Hele-Shaw Flows with Strong Quenched Disorder

We report experimental evidences of anomalous kinetic roughening in the stable displacement of an oil-air interface in a Hele-Shaw cell with strong quenched disorder. The disorder consists on a random modulation of the gap spacing transverse to the growth direction (tracks). We have performed experiments varying average interface velocity and gap spacing, and measured the scaling exponents. We have obtained beta=0.50, beta*=0.25, alpha=1.0, alpha_l=0.5, and z=2. When there is no fluid injection, the interface is driven solely by capillary forces, and a higher value of beta around beta=0.65 is measured. The presence of multiscaling and the particular morphology of the interfaces, characterized by high slopes that follow a L\'evy distribution, confirms the existence of anomalous scaling. From a detailed study of the motion of the oil--air interface we show that the anomaly is a consequence of different local velocities over tracks plus the coupling in the motion between neighboring tracks. The anomaly disappears at high interface velocities, weak capillary forces, or when the disorder is not sufficiently persistent in the growth direction. We have also observed the absence of scaling when the disorder is very strong or when a regular modulation of the gap spacing is introduced.Comment: 14 pages, 17 figure

Presència del bivalve invasor Sinanodonta woodiana (Lea, 1834) al delta del Llobregat (Baix Llobregat)

El delta del Llobregat és una de les zones humides més importants de Catalunya. Disposa d’una malacofauna força diversa, encara que amenaçada a causa de la proximitat a l’àrea urbana de Barcelona i al fet d’estar envoltada per grans infraestructures. Aquest article registra per primera vegada la presència i distribució en aquest espai natural d’un bivalve invasor, la nàiade asiàtica Sinanodonta woodiana, del qual se n’han trobat nombrosos exemplars i que presenta una població ben establerta.Presence of the invasive bivalve Sinanodonta woodiana (Lea, 1834) in the Llobregat delta (Baix Llobregat)The Llobregat delta is among the most important wetlands in Catalonia. The diverse  malacofauna of the area is threatened, however,  by the large infrastructures surrounding the delta  and the area´s  close proximity to the urban centre  of Barcelona. Here we present the first report on  invasive bivalves in the delta  following  findings of a well-established population  of the Chinese pond mussel, Sinanodonta woodiana. The  distribution of the species in  this natural area is also discussed.Presencia del bivalvo invasor Sinanodonta woodiana (Lea, 1834) en el delta del Llobregat (Baix Llobregat) El delta del Llobregat es una de las zonas húmedas más importantes de Cataluña. Dispone de una malacofauna muy diversa, aunque amenazada debido a su proximidad al área urbana de Barcelona y a que está rodeada por grandes infraestructuras. Este artículo registra por primera vez la presencia y distribución en este espacio natural de un bivalvo invasor, la almeja china del cieno Sinanodonta woodiana, del que se han encontrado numerosos ejemplares y presenta una población bien establecida

Prescribing curvatures in the disk via conformal changes of the metric: the case of negative Gaussian curvature

This paper deals with the question of prescribing the Gaussian curvature on a disk and the geodesic curvature of its boundary by means of a conformal deformation of the metric. We restrict ourselves to a symmetric setting in which the Gaussian curvature is negative, and we are able to give general existence results. Our approach is variational, and solutions will be searched as critical points of an associated functional. The proofs use a perturbation argument via the monotonicity trick of Struwe, together with a blow-up analysis and Morse index estimates. We also give a nonexistence result that shows that, to some extent, the assumptions required for existence are necessary.Comment: 24 pages and 3 figure

Using hydrogeomorphological interpretation to improve runoff-threshold estimation in mediterranean ephemeral streams (ramblas)

The runoff threshold (P0) is one of the key parameters in the study of catchment hydrological response. It is fundamental in the analysis of rainfall-runoff conversion processes, for estimating water budgets and for describing the genesis of hortonian overland flow, as it provides information on the precipitation losses within the fluvial systems, from the start of the episode until runoff is produced. There are several methods for estimating this parameter. In the case of small semiarid and Mediterranean basins, complex models are not suitable due to the specific conditions of these environments as well as the quantity of data required for the models. In these environments, empirical methods have demonstrated to be more effective. One of the most used models in Spain is that developed by the US Soil Conservation Service (SCS) in 1972, and modified by Témez (1978, 1991). This is a simple, easy to apply model, which uses slope values, vegetation, land use and soil hydrological group data. In spite of the generalized application of the model and its multiple adaptations, there are still many uncertainties, mainly related to the soil hydrological groups which, together with land use, are the most sensitive variables in runoff threshold estimation. These uncertainties are especially important in small semiarid basins and Mediterranean ephemeral streams where soils are generally very heterogeneous, not well developed, highly dependent on underlying rock and have been heavily exploited. In order to improve runoff threshold estimation in semiarid environments, some authors have included detailed information about soils in the model but without improving the results significantly. Others have assigned the soil hydrological group directly from lithology, without considering soil type. This paper proposes some modifications to the SCS method related to the assignation of the soil hydrological group in order to improve runoff threshold estimation in Mediterranean basins. In these environments, hydrological behavior is highly determined by the strong interaction between geomorphological structure, lithology and edaphology. These three variables are combined at basin scale, in order to assign the soil hydrological group with the aim of using hidrogeomorphological interpretation to improve runoff threshold estimation. The method has been applied, using GIS, to several small basins located in the Mediterranean Spanish region. Although the estimation of runoff threshold using a GIS is a process which can be easily automated, the proposed modification requires the expert geomorphological knowledge of the catchment. Runoff thresholds obtained with this method are presented here. Although the results have to be checked with runoff threshold data obtained by water budget, so far they are consistent with the expected values for the study area from literature references

Interleukin-15 antagonizes muscle protein waste in tumour-bearing rats

Tissue protein hypercatabolism (TPH) is an important feature in cancer cachexia, particularly with regard to the skeletal muscle. The Yoshida AH-130 rat ascites hepatoma is a model system for studying the mechanisms involved in the processes that lead to tissue depletion, since it induces in the host a rapid and progressive muscle wasting, primarily due to TPH. The present study was aimed at investigating if IL-15, which is known to favour muscle fibre hypertrophy, could antagonize the enhanced muscle protein breakdown in this cancer cachexia model. Indeed, IL-15 treatment partly inhibited skeletal muscle wasting in AH-130-bearing rats by decreasing (8-fold) protein degradative rates (as measured by14C-bicarbonate pre-loading of muscle proteins) to values even lower than those observed in non-tumour-bearing animals. These alterations in protein breakdown rates were associated with an inhibition of the ATP-ubiquitin-dependent proteolytic pathway (35% and 41% for 2.4 and 1.2 kb ubiquitin mRNA, and 57% for the C8 proteasome subunit, respectively). The cytokine did not modify the plasma levels of corticosterone and insulin in the tumour hosts. The present data give new insights into the mechanisms by which IL-15 exerts its preventive effect on muscle protein wasting and seem to warrant the implementation of experimental protocols involving the use of the cytokine in the treatment of pathological states characterized by TPH, particularly in skeletal muscle, such as in the present model of cancer cachexia. © 2000 Cancer Research Campaig

Experimental analysis of cyclical dispersion in compression-ignited versus spark-ignited engines and its significance for combustion noise numerical modeling

[EN] As noise pollution remains one of the biggest hurdles posed by thermal engines, increasing efforts are made to alleviate the generation of combustion noise from the early design stage of the chamber. Since the complexity of both modern chamber geometries and the combustion process itself precludes robust analytic solutions, and since the resonant, highly 3D pressure field is difficult to be measured experimentally, focus is put on the numerical modelling of the process. However, in order to optimize the resources devoted to this simulation, an informed decision must be made on which formulations are followed. In this work, the experimental cyclic dispersion of the in-cylinder pressure is analyzed in two typical compression-ignited (CI) and spark-ignited (SI) engines. Acoustic signatures and pressure rise rates are derived from this data, showing how while the preponderance of flame front propagation and dependency of previous cycle in SI engine noise usually calls for multi-cycle, more complex turbulence modelling such as Large Eddy Simulation (LES), simpler Unsteady Reynolds-Averaged Navier-Stokes (URANS) formulations can accurately characterize the more consistent pressure spectra of CI thermal engines, which feature sudden autoignition as the main noise source.European Regional Development Fund (Dotacion de infraestructuras cientifico tecnicas para el Centro Integral de Mejora Energetica y Medioambiental de Sistemas de Transporte, CiMeT) (FEDER-ICTS-2012-06). Programa de Apoyo para la Investigacion y Desarrollo (PAID) Universitat Politecnica de Valencia (FPI-S2-2016-1353).Broatch, A.; López, JJ.; Garcia Tiscar, J.; Gómez-Soriano, J. (2018). Experimental analysis of cyclical dispersion in compression-ignited versus spark-ignited engines and its significance for combustion noise numerical modeling. Journal of Engineering for Gas Turbines and Power. 140(10):102808-1-102808-8. https://doi.org/10.1115/1.4040287S102808-1102808-81401

Mediators of cachexia in cancer patients

Alterations in amino acid and protein metabolism particularly in skeletal muscle are a key feature of cancer that contributes to the cachexia syndrome. Thus, skeletal muscle protein turnover is characterized by an exacerbated rate of protein degradation, promoted by an activation of different proteolytic systems that include the ubiquitin-proteasome and the autophagic-lysosomal pathways. These changes are promoted by both hormonal alterations and inflammatory mediators released as a result of the systemic inflammatory response induced by the tumor. Other events, such as alterations in the rate of myogenesis/apoptosis and decreased regeneration potential also affect skeletal muscle in patients with cancer. Mitochondrial dysfunction also contributes to changes in skeletal muscle metabolism and further contributes to the exacerbation of the cancer-wasting syndrome. Different inflammatory mediators either released by the tumor or by the patient's healthy cells are responsible for the activation of these catabolic processes that take place in skeletal muscle and in other tissues/organs, such as liver or adipose tissues. Indeed, white adipose tissue is also subject to extensive wasting and 'browning' of some of the white adipocytes into beige cells; therefore increasing the energetic inefficiency of the patient with cancer. Recently, an interest in the role of micromRNAs either free or transported into exosomes has been related to the events that take place in white adipose tissue during cancer cachexia

Potential reactivity of the andesitic rocks from Cabo de Gata (SE Spain)

8 páginas, 4 figuras, 3 tablas.[ES] Las rocas andesíticas producen una reacción álcalis-sílice con los componentes de la fase intersticial del hormigón. Esta reacción puede encuadrarse dentro de las de cinética lenta, ya que la disolución incongruente de los minerales constituyentes de las rocas, da lugar a la formación tardía de geles silicocalco- alcalinos. En consecuencia, la utilización convencional del método de ensayo de barras de mortero no detecta la reacción hasta transcurridos al menos 90 días.[EN] Andesitic rocks produce an alkali-silica reaction with the components of the interstitial phase of concrete. This reaction can be considered as belonging to the slow-kinetic type, since the incongruent dissolution of the rock-forming minerals leads to the late formation of siliceous calc-alkaline gel. As a conquence, the conventional mortar-bar method does not detect such reaction until 90 days later.Peer reviewe

Síntesis y caracterización de óxidos mixtos precursores de bronces tetragonales de W de potencial actividad en la oxidación de difenilsulfuro

Fases de heteropolioxometalatos (HPOM), a base de heteropolitungstatos complejos derivados de tipo Keggin de la serie [M4(H2O)2(PW9O34)2]10- (PWM) con M(II) = Cu y su precursor Na8H(PW9O34) (PW9), se han modificado químicamente mediante reacción hidrotermal, con iones Nb y V en el gel de síntesis, dando lugar a la formación de materiales del tipo (KNaCu)xP0.11WV0,2NbOx y (Na)xPWV0,2NbOx. Tanto los materiales de síntesis como los tratados a 500ºC (en atmosfera de N2) son pseudocristalinos (que tras tratamiento a 800º C, conduce a una estructura típica de bronce tetragonal). Los materiales tratados térmicamente a 500ºC se han caracterizado y estudiado como catalizadores en la oxidación parcial de difenilsulfuro. Los resultados catalíticos se han comparado con los obtenidos con los HPOM de partida, observándose que los bronces metálicos presentan una mayor actividad catalítica (con una drástica disminución del tiempo de reacción) y un marcado aumento de la selectividad a difenil-sulfona.Phases based on complex heteropolytungstates (HPOM), derived from series Keggin type [M4 (H2O)2 (PW9O34)2] 10-(PWM) with M(II) = Cu and its precursor Na8H (PW9O34) (PW9), have been chemically modified by hydrothermal reaction, with Nb and V ions in the synthesis gel, giving place materials as (KNaCu)xP0.11WV0,2NbOx and (Na)xPWV0,2NbOx. The as-synthesized and the heat-treated at 500ºC (in N2) are pseudocrystalline (although they are transformed to tetragonal bronze after heattreatment at 800ºC). The samples heat-treated at 500ºC have been characterized and tested in the partial oxidation of diphenylsulfide. The catalytic results have been compared to those achieved over pure HPOM. It has been observed that these metal oxides bronzes show a higher both catalytic activity (with a drastic reduction of the reaction time) and selectivity to diphenyl-sulfone

Nonmuscle tissues contribution to cancer cachexia

Cachexia is a syndrome associated with cancer, characterized by body weight loss, muscle and adipose tissue wasting, and inflammation, being often associated with anorexia. In spite of the fact that muscle tissue represents more than 40% of body weight and seems to be the main tissue involved in the wasting that occurs during cachexia, recent developments suggest that tissues/organs such as adipose (both brown and white), brain, liver, gut, and heart are directly involved in the cachectic process and may be responsible for muscle wasting. This suggests that cachexia is indeed a multiorgan syndrome. Bearing all this in mind, the aim of the present review is to examine the impact of nonmuscle tissues in cancer cachexia