Nonreactive solute transport in soil columns: classical and fractional-calculus modeling

Vertical nonreactive solute transport data collected in three laboratory soil columns (made out of sediment samples from the Pampean aquifer located southeast of the Buenos Aires province) are contrasted with the explicit solutions of two model 1D linear PDEs: the classical advection–dispersion equation (ADE), and a fractional advection–dispersion equation (FADE) which has proven to be a useful modeling tool for highly inhomogeneous media exhibiting nontrivial scaling laws. Whereas two of the samples turn out to be quite homogeneous (thus requiring a fractional-derivative order γ → 2), the third one is best described by a FADE with fractional-derivative order γ = 1.68. This example illustrates the FADE’s ability to reveal self-similar geometric structures inside the sample.Fil: Benavente, Micaela Andrea. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Matemática; ArgentinaFil: Deza, Roberto Raul. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Físicas de Mar del Plata. Universidad Nacional de Mar del Plata. Facultad de Cs.exactas y Naturales. Instituto de Investigaciones Físicas de Mar del Plata; ArgentinaFil: Grondona, Sebastian. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Geología de Costas y del Cuaternario. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Geología de Costas y del Cuaternario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mascioli, S.. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Geología de Costas y del Cuaternario. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Geología de Costas y del Cuaternario; ArgentinaFil: Martinez, Daniel Emilio. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Geología de Costas y del Cuaternario. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Geología de Costas y del Cuaternario; Argentin

A longitudinal retrospective study on intracranial arterial pulsatility index: its evolution in ten years' time and how it relates to the occurrence of cerebral and systemic ischemic disease

BACKGROUND AND AIMS: Intracranial arterial pulsatility index (PI) has been related to old age, hypertension, diabetes and small vessel disease. However, the cross- sectional design of most studies prevents a proper assessment of causality and evolution. We sought to explore how this index changes through time, which conditions affect this evolution and whether or not it can predict the occurrence of future ischemic events. METHODS: Between the years 2001-2006, 1288 patients underwent a transcranial Doppler evaluation in the Department of Neurology of the Hospital Universitario Central de Asturias. PI values for the middle cerebral and basilar arteries were systematically annotated. After exclusion of deceased patients and significant large artery stenoses, 89 patients were recruited for a re-evaluation in 2012. Afterwards, the sample was expanded up to 150 patients, with 61 randomly selected patients –either alive or deceased- who did not undergo a second exploration. Both groups had their clinical files reviewed, with special attention to vascular risk factors and brain or coronary ischemic events. RESULTS AND DISCUSSION: Our results pointed to the following conclusions: • Intracranial arterial PI works as a dynamic measure of both cerebral and systemic vascular disease. • Age is the main factor influencing PI value and variation, but, within a certain age group, PI is able to point subjects at higher long-term risk of future ischemic events. • Basilar artery PI seems to be a better predictor of future cerebral and coronary ischemic disease than middle cerebral artery PI

Tectonic and climatic controls on the Chuquibamba landslide (western Andes, southern Peru)

The contribution of landslides to the Quaternary evolution of relief is poorly documented in arid contexts. In southern Peru and northern Chile, several massive landslides disrupt the arid western Andean front. The Chuquibamba landslide, located in southern Peru, belongs to this set of large landslides. In this area, the Incapuquio fault system captures the intermittent drainage network and localizes rotational landslides. Seismic activity is significant in this region with recurrent Mw9 subduction earthquakes; however, none of the latest seismic events have triggered a major landslide. New terrestrial cosmogenic dating of the Chuquibamba landslide provides evidence that the last major gravitational mobilization of these rotational landslide deposits occurred at ~ 102 ka, during the Ouki wet climatic event identified on the Altiplano between 120 and 98 ka. Our results suggest that wet events in the arid and fractured context of the Andean forearc induced these giant debris flows. Finally, our study highlights the role of tectonics and climate on (i) the localization of large Andean landslides in the Western Cordillera and on (ii) the long-term mass transfer to the trench along the arid Andean front

Iconography of the corpse in the public sphere. Presence and absence of the dead body in times of pandemic

In this article, we examine the visual motif of the corpse and its presence in the public sphere in times of pandemic from an iconographic, political and anthropological perspective. Through the analysis of the representation of the dead body in images presented by modern media, we reflect on how the formal and iconographic schemes of presentation of death were transformed following the irruption of the Covid-19 pandemic in March 2020. The pandemic scheme, which is unusual from a political and anthropological perspective, assumes a particular approach to the problem of the representation of the dead body (anonymous body, carrier of a virus), encrypted in a dialectic between systematic omission and censorship and displacement of the representation of death towards the cumulative symmetry of empty pits or coffins that prefigure the corpse to come. Pandemic iconography, often based on science fiction imagery, outlines the dehumanized restlessness of a dystopian future. Under these exceptional conditions, some corpses, which are a priori anonymous, stand out, showing, even in the suspended space of Covid-19, the permanence of structural schemes of violence that must be denounced and fought in the present. With that in mind, we also examine the corpses claimed by Black Lives Matter and their distinctive representations, which are very different from those of the victims of the epidemic. Finally, through these references and based on the media treatment of Diego Armando Maradona’s body, we consider the significance of the return of the iconic corpse to the center of the public sphere, which imposes a regime of extreme visibility and goes beyond the representative limits of pandemic exceptionality.En este artículo estudiamos, desde una perspectiva iconográfica, política y antropológica, el motivo visual del cadáver y su presencia en la esfera pública en tiempos de pandemia. A partir del análisis de la representación del cuerpo muerto en las imágenes de los medios de comunicación actuales, hemos tratado de pensar cómo se transformaron los esquemas formales e iconográficos de presentación de la muerte con la irrupción, desde marzo de 2020, de la pandemia de Covid-19. El régimen pandémico, excepcional a nivel político y antropológico, supone un acercamiento particular a la problemática de la representación del cuerpo muerto (cuerpo anónimo, portador de un virus), cifrado en una dialéctica entre un régimen de omisión y censura y el desplazamiento de la representación de la muerte hacia la simetría acumulativa de las fosas o ataúdes vacíos que prefiguran el cadáver por venir. La iconografía pandémica, construida con frecuencia sobre el imaginario de la ciencia-ficción, perfila la inquietud deshumanizada de un futuro distópico. En esas condiciones de excepcionalidad, algunos cadáveres, a priori anónimos, se singularizan, mostrando, aún en el espacio en suspenso de la Covid-19, la permanencia de esquemas estructurales de violencia que se deben denunciar y combatir en presente. En ese sentido, proponemos también estudiar los cadáveres reivindicados por el Black Lives Matter y la peculiar forma representativa que toman, muy diferente a los de las víctimas de la epidemia. Finalmente, desde estas coordenadas y a partir del tratamiento mediático del cuerpo de Diego Armando Maradona, consideramos como significativo el retorno al centro de la esfera pública del cadáver icónico, que impone un régimen de extrema visibilidad y desborda los límites representativos de la excepcionalidad pandémica

Characterization of an engineered cellulose based membrane by thiol dendrimer for heavy metals removal

Diaminobutane based poly(propyleneimine) dendrimer functionalized with sixteen thiol groups, DAB-3-(SH)16, was successfully embeded in a swollen cellulosic support in order to achieve an easily handle engineered membrane. The membrane was characterised by physicochemical, electrical and transport measurements, and the effect of the dendrimer was established by comparing these results with those obtained for the original cellulosic support. Results show that dendrimer inclusion improves the membrane elastic behaviour (Young modulus increase around 20%), while a significant reduction in the permeation of toxics heavy metals (Cd2+, Hg2+ and Pb2+) was also obtained, which avails the possible application of dendrimer-modified membrane in electrochemical devices for water remediationThe authors would like to thanks to Andalucía Tech Program (Universidad de Málaga, Spain) and the CICYT (MINECO, Spain, research project CTQ/2011-27770 FEDER funds) for partial financial support. Spanish Ministerio de Ciencia e Innovación (Project CTQ2009-12332-C02-01) is also acknowledge

Machine learning predicts accurately mycobacterium tuberculosis drug resistance from whole genome sequencing data

Background: Tuberculosis disease, caused by Mycobacterium tuberculosis, is a major public health problem. The emergence of M. tuberculosis strains resistant to existing treatments threatens to derail control efforts. Resistance is mainly conferred by mutations in genes coding for drug targets or converting enzymes, but our knowledge of these mutations is incomplete. Whole genome sequencing (WGS) is an increasingly common approach to rapidly characterize isolates and identify mutations predicting antimicrobial resistance and thereby providing a diagnostic tool to assist clinical decision making. Methods: We applied machine learning approaches to 16,688 M. tuberculosis isolates that have undergone WGS and laboratory drug-susceptibility testing (DST) across 14 antituberculosis drugs, with 22.5% of samples being multidrug resistant and 2.1% being extensively drug resistant. We used non-parametric classification-tree and gradientboosted-tree models to predict drug resistance and uncover any associated novel putative mutations. We fitted separate models for each drug, with and without “co-occurrent resistance” markers known to be causing resistance to drugs other than the one of interest. Predictive performance was measured using sensitivity, specificity, and the area under the receiver operating characteristic curve, assuming DST results as the gold standard. Results: The predictive performance was highest for resistance to first-line drugs, amikacin, kanamycin, ciprofloxacin, moxifloxacin, and multidrug-resistant tuberculosis (area under the receiver operating characteristic curve above 96%), and lowest for thirdline drugs such as D-cycloserine and Para-aminosalisylic acid (area under the curve below 85%). The inclusion of co-occurrent resistance markers led to improved performance for some drugs and superior results when compared to similar models in other largescale studies, which had smaller sample sizes. Overall, the gradient-boosted-tree models performed better than the classification-tree models. The mutation-rank analysis detected no new single nucleotide polymorphisms linked to drug resistance. Discordance between DST and genotypically inferred resistance may be explained by DST errors, novel rare mutations, hetero-resistance, and nongenomic drivers such as efflux-pump upregulation. Conclusion: Our work demonstrates the utility of machine learning as a flexible approach to drug resistance prediction that is able to accommodate a much larger number of predictors and to summarize their predictive ability, thus assisting clinical decision making and single nucleotide polymorphism detection in an era of increasing WGS data generation

Observations and dynamical implications of active normal faulting in South Peru

SUMMARY Orogenic plateaus can exist in a delicate balance in which the buoyancy forces due to gravity acting on the high topography and thick crust of the plateau interior are balanced by the compressional forces acting across their forelands. Any shortening or extension within a plateau can indicate a perturbation to this force balance. In this study, we present new observations of the kinematics, morphology and slip rates of active normal faults in the South Peruvian Altiplano obtained from field studies, high-resolution DEMs, Quaternary dating and remote sensing. We then investigate the implications of this faulting for the forces acting on the Andes. We find that the mountains are extending ∼NNE–SSW to ∼NE–SW along a normal fault system that cuts obliquely across the Altiplano plateau, which in many places reactivates Miocene-age reverse faults. Radiocarbon dating of offset late Quaternary moraines and alluvial fan surfaces indicates horizontal extension rates across the fault system of between 1 and 4 mm yr–1—equivalent to an extensional strain rate in the range of 0.5–2 × 10−8 1 yr–1 averaged across the plateau. We suggest the rate and pattern of extension implies there has been a change in the forces exerted between the foreland and the Andes mountains. A reduction in the average shear stresses on the sub-Andean foreland detachment of ≲4 MPa (20–25 per cent of the total force) can account for the rate of extension. These results show that, within a mountain belt, the pattern of faulting is sensitive to small spatial and temporal variations in the strength of faults along their margins.Denman Baynes Senior Studentship, Clare College Cambridge Arup Santander Mobility Grant (University of Cambridge

Acta Congregationis Prouincialis Prouinciae Hispaniae Ordinis Praedicatorum celebratae in Conuentu Sancti Dominici Benauentani ... die vigesima tertia Aprilis ... 1673, sub R.A.P.N. Fr. Francisco de Vria, magistro Prouinciali electo eiusdem Prouincia

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-2010Texto fechado en 1673Sign.: A-D4, F2Port. con esc. xil. de los Dominico

Determination of hydraulic parameters in experimental soil columns from the southeast of Buenos Aires province

La cuenca del Río Quequén Grande constituye una región representativa de los sistemas agrícolas pampeanos. El acuífero en esta región es la principal fuente de abastecimiento de agua para todos los usos, lo que pone de manifiesto la importancia de desarrollar los elementos necesarios para el estudio de la movilidad de los contaminantes a través de los suelos hacia la zona saturada. El objetivo del presente trabajo fue obtener parámetros hidráulicos bajo condiciones de saturación en columnas intactas de distintos tipos de suelos de la región, contemplando suelos de uso agrícola y natural. Se estudiaron dos series de suelo: Serie Azul y Serie Semillero Buck, con muestras tomadas en dos sectores próximos a las localidades de Lobería y La Dulce, respectivamente. Las columnas fueron eluidas con una solución acuosa de iones cloruro y se midió el incremento progresivo de conductividad. A partir de las curvas de arribo obtenidas, se ajustó la ecuación de transporte, obteniendo los valores de dispersividad y porosidad. Dichos parámetros no presentaron diferencias significativas según el uso para los suelos de Lobería, de textura franco arcillosa, indicando que la labranza no produciría modificaciones evidentes en el perfil del suelo. En La Dulce, donde los suelos poseen una textura más arenosa, los parámetros variaron según el uso del suelo, presentando una mayor dispersividad y menor porosidad del suelo bajo explotación agrícola extensiva.The Quequén Grande river basin is representative of the farming systems from the Pampas region. The aquifer is the main source of water supply for all uses, which highlights the importance to study the mobility of contaminants through the soil to the saturated zone. The aim of this study was to obtain hydraulic parameters of different soil types in the region according to land use (agricultural and natural) under saturated conditions. Two study areas were selected close to the cities La Dulce (Azul Series Soil) and Lobería (Semillero Buck Series Soil), as representatives of the dominant soil types in this area. The columns were eluted with an aqueous solution containing chloride ions and the progressive increase was measured at the end of the column. From the experimental data the breakthrough curve was adjusted using MATLAB software while dispersivity and porosity values were determined from modeled data. These parameters did not differ significantly in Lobería, so it is assumed that tillage does not produce significant changes in the soil profile. Conversely, in La Dulce land use affects the hydraulic properties of the soil leading to lower porosity and higher dispersivity values in soils under tillage use.Fil: Grondona, Sebastián I.. Universidad Nacional de Mar del PlataFil: Martínez, Daniel E.. Universidad Nacional de Mar del PlataFil: Benavente, Miguel. Universidad Nacional de Mar del PlataFil: Gonzalez, Mariana. Universidad Nacional de Mar del PlataFil: Massone, Héctor E.. Universidad Nacional de Mar del PlataFil: Miglioranza, Karina S. B.. Universidad Nacional de Mar del Plat

Physical-mechanical properties of a granite used in the UNESCO World Heritage of the north of Portugal after high-temperature pretreatment

This paper studies the evolution of physical and mechanical properties of 46 cubic samples of a granite widely used in the UNESCO World Heritage of the north of Portugal pre-treated at different temperatures (between 105 and 700 °C) and cooled under different conditions (i.e., aircooled and water-cooled). The results showed that specific gravity and mineralogy did not exhibit significant changes after the thermal pre-treatment. In contrast, density, porosity, ultrasonic properties, uniaxial compressive strength and elastic modulus showed important variations, mainly at temperatures higher than 500 ºC. The SEM analyses clearly show an increase in the density of cracks, as well as in the width and length of the cracks from 500 ºC. Furthermore, it was observed an amplification of the damage in those samples cooled by water immersion. These results are of relevance for the evaluation of the integrity level of buildings built using this rock after a fire.This work was partially funded by the University of Alicante (UAUSTI18-21, UAUSTI19-25 and UAUSTI20-20 projects), the Regional Governments of Comunidad Valenciana AICO/2020/175 and CIAICO/2021/335, the Spanish Ministry of Economy and Competitiveness (MINECO) and EU FEDER under Project TEC2017-85244-C2-1-P, and the Spanish Ministry of Education, Culture and Sport under project CAS17/00392. The authors also want to thank Idael F. Blanco of the Departamento de Ciencias de la Tierra de la Universidad de Alicante for the petrographic description of the thin section