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Many disciplines have approached the study of human motor behavior. The motor learning theory based on information processing proposes a learning loop through interaction between the external environment and the central nervous system. Different neuroscience fields and technological advances provide a new perspective for the intensive study of the intrinsic processes of motor behavior, which modify the most visible aspect: motor efficiency. The aim of the present review was to determine which cortical and muscular electrophysiological biomarkers available in the literature could be representative for the study and quantification of motor efficiency. In this review, a survey of the literature related to motor production has been performed. The continuous development of biological signal monitoring techniques has allowed to understand part of the communication methods of the central nervous system, the integration of neural networks, and the interaction between different anatomic structures through rhythmic patterns of discharge known as brain waves. Motor production has been characterized by detecting electrophysiological biomarkers, taking into account the connectivity that can be represented by the corticomuscular and intermuscular coherence indices in different frequency bands. The present work proposes an approach to use these biomarkers on beta-band (for muscle stability synergies) and gamma-band (for mobility synergies). These indices will allow establishing quantitative parameters for motor efficiency, which could improve the precision of sports assessment.

Contamination of water with arsenic is a major global health problem. The use of adsorbent materials for the removal of As from aqueous systems is a plausible solution to this problem. In this work, the use of commercial bentonites (purified and modified with iron (III)) for the removal of As from water was studied. The samples were characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier Transformed Infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and nitrogen adsorption/desorption isotherms to determine their physicochemical properties. The arsenic removal capacities of adsorbent materials were studied from 1 mg/L solutions of As (III) using the colorimetric technique of molybdenum blue. High adsorption capacity (0.33 mg/g) of As (III) was obtained in aqueous systems after 1 h of treatment with unmodified bentonite. The incorporation of iron improved the removal performance in short times. The obtained results could be the starting point for the development of a low-cost filtration system that contributes to solve the problem of arsenic in water.

While there are many existing technologies for treating water, many of them are expensive, inefficient, or not environmentally friendly. The application of green materials in water and wastewater treatment and pollution cleanup is promising, as demonstrated by an increasing number of investigations. However, although many of them show great potential for full-scale water treatment and environmental remediation, limited studies regarding pilot and full-scale developments can be found in literature and remain at the concept stage. This review focuses on the potential of various green-based adsorbents for nitrate, phosphate, and fluoride removal from water and wastewater. A summary of relevant published data with some of the latest important findings and up-to-date literature revision is presented, and the results are discussed.

Arsenic (As) is a major source of water contamination that has both natural and anthropogenic origins, so that, to remove it from water is a relevant topic. Taking into account the ease of operation, the cost of processing and the required instrumentation, adsorption processes could be considered as very convenient alternative technologies for water remediation. The present research work is focused on the development and characterization of eco-friendly polyvinyl alcohol (PVA) and alginate (Alg) hydrogel beads containing natural bentonite (Bent) as potential useful devices for As removal from polluted water. Composite beads with different PVA/Alg proportions (75/25 and 50/50) with and without 30 wt.% Bent were prepared by ionic gelation. The obtained beads were thoroughly characterized by means of thermal analysis (differential scanning calorimetry and thermogravimetric analysis), crosslinking degree by evaluating the gel fraction (GF), the capacity of swelling, morphological aspects (by Scanning Electron Microscopy), functional groups and interactions (by FTIR) and finally, the performance of the beads as arsenic adsorbent was tested by treating batch aqueous solutions. Morphological investigations showed that wet beads were highly porous and spherical. Moreover, the beads with the highest PVA content absorbed higher amounts of water whereas the incorporation of clay to the hydrogels produced a reduction on the swelling degree and an increase of GF. The adsorption behavior of the pearls towards As was studied in terms of PVA/Alg ratio, clay loading and contact time. The results clearly demonstrated that the clay inclusion plays a key role in the As removal since unfilled PVA/Alg beads were not able to remove it. The FTIR spectra of beads after As removal show the partial migration of the components of the beads, which can be associated with the intermediate crosslinking degree and almost amorphous state within the matrix. Fil: Baigorria, Estefanía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Cano, Leonardo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Sanchez, Laura Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Alvarez, Vera Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Ollier Primiano, Romina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina

Fil: Baigorria, Estefania. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnologia de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingenieria. Instituto de Investigaciones en Ciencia y Tecnologia de Materiales; Argentina

En la región periurbana de La Plata se destaca la producción de hortalizas frescas llevada a cabo por pequeños agricultores familiares. En el marco de las problemáticas de hábitat y salud, se observa una serie de sintomatologías que afectan tanto a los productores/trabajadores y sus familias –principalmente los chicos que allí habitan– como así también a los consumidores de los productos hortícolas. Estas sintomatologías tienen como origen principal la utilización de agua no potable. El trabajo se propone determinar el tipo y magnitud de la contaminación del agua, identificar los causales del mismo y evaluar alternativas que resuelvan el presente inconveniente. Los resultados indican que una problemática compleja como la planteada, requiere que las soluciones tecnológicas sean acompañadas de acciones políticas que modifiquen condiciones estructurales de la vida de los productores en el cinturón hortícola platense., The peri-urban region of La Plata stands out in the production by small family farmers of fresh vegetables. Within the framework of the problems of habitat and health, a series of symptomatologies are observed that affect both the producers / workers and their families –mainly the children who live there– as well as the consumers of the horticultural products. These symptomologies have as their main source the utilizationof non-potable water. The work aims to determine the type and magnitude of water pollution, identify the causes thereof and evaluate technological alternatives that solve the present problem. The results indicate that a complex problem, such as the one proposed, requires technological solutions to be accompanied by political actions that modify the structural conditions of the producers' lives in the La Plata horticultural belt., Na região periurbana de La Plata, destaca-se a produção de hortaliças frescas realizadas por pequenos agricultores familiares. Como parte das questões de hábitat e saúde, observa-se uma série de sintomas que afetam tanto os produtores/trabalhadores e suas famílias –principalmente as crianças que vivem lá– como os consumidores dos produtos hortícolas. Essas sintomatologias têm como principal origem o uso de água não potável. O trabalho visa determinar o tipo e magnitude da contaminação da água, identificar suas causas e avaliar alternativas que resolvam o problema atual. Os resultados indicam que um problema complexo como o apresentado, exige que as soluções tecnológicas sejam acompanhadas de ações políticas que modifiquem condições estruturais da vida dos produtores no cinturão hortícola de La Plata., Facultad de Ciencias Exactas, Facultad de Ciencias Agrarias y Forestales

We realized a study of the shortest path fractal dimension in three dimensions for randomly crumpled paper balls. We took measurements between all possible combinations of pairs of points in crumpled and flat configurations, we found that a correlation between these distances exist, even more, such mean experimental value is dmin=1.2953±0.02 that coincides almost numerically with the very known 3D shortest path fractal dimension for percolation systems reported in computational simulations.

The effect of support and promoters on the catalytic properties of Fe supported in the FTS was studied. Precursors of supported Fe on SiO2 and SBA −15 were synthesized and doped with Cu and K. The precursors were activated in pure H2 and catalytically tested with a mixture of H2:CO = 2:1, T = 543 K and P = 10 bar. The samples were characterized by atomic absorption, N2 adsorption, X-ray diffraction, TEM and TPR. Also, we used the DFT to study the changes of the electronic structure when the Fe, K and Cu are adsorbed on the SBA-15 surface. The incorporation of different ions do not alter the structural and textural properties of the support. In the FTS, all the catalysts supported on SBA-15 presented a low selectivity towards methane and a promising hydrocarbon production in the range of gasoline, showing positive effect of the support for iron catalysts for the FTS reaction. The activity order obtained was: Fe/K-SBA-15 > Fe/Cu-SBA–15 ≈ Fe-SBA–15 > Fe-SiO2, which is the same order for the selectivity towards olefins. The presence of K on the SBA-15 surface increases the activity and selectivity towards olefins; an effect that can be attributed to the electrostatic effect generated by the alkaline ions. Fil: Cano, Leonardo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; Argentina Fil: Garcia Blanco, Andres Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada ; Argentina Fil: Lener, German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada ; Argentina Fil: Marchetti, Sergio Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata, Facultad de Ciencias Exactas; Argentina Fil: Sapag, Manuel Karim. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada ; Argentina

El objetivo del presente estudio ha sido evaluar la influencia de un protocolo de entrenamiento intervalado de alta intensidad de carrera lineal en el rendimiento aeróbico de rugbistas varones de 15 y 16 años. Treinta y tres sujetos participaron voluntariamente. Se tomaron mediciones antropométricas y estimaciones del consumo máximo de oxígeno (VO2max) para caracterizar el estado físico inicial. Se estimó la velocidad aeróbica máxima para programar individualmente las distancias de entrenamiento. El protocolo se organizó en seis sesiones divididas en tres semanas, consistentes en dos bloques de doce repeticiones con intervalos de trabajo de diez segundos de carrera lineal y diez segundos de pausa pasiva. Luego de las seis sesiones se tomaron nuevamente las estimaciones de VO2max. Se utilizaron pruebas no paramétricas para el tratamiento estadístico. El grupo experimental logró un incremento significativo del VO2max del 12% (p

A mesoporous SBA‐15 solid is doped with Li, K, or Cs. These systems are used as support of iron nanoparticles, and each composite is utilized as a catalyst in the Fischer-Tropsch synthesis. After the activation treatment, the same Fe species are detected in all solids: Fe3O4, α‐Fe, and Fe2+ inside SBA‐15 walls. However, the species percentages and their distribution are different according to the dopant present. In all "working" catalysts, a mixture of carbides ε´‐Fe2.2C and χ‐Fe2C5, Fe3O4, and ions Fe+2 inside the SBA‐15 walls are found. Alkali cations produce different amounts and strengths of basic sites. At 1 atm and T = 703 K, the catalytic activity order is: Li > K > no doped > Cs, and the alkali metals favor the production of olefins. At 20 atm, the activity is considerably higher, even at a temperature as low as 543 K, which is attributed to structural properties of the support and to diffusional effects. All catalysts show a promising hydrocarbon production in the gasoline range. The influence of alkali metals is discussed in terms of electrostatic effects, and the limited hydrocarbon chain growth is attributed to the control over size of active iron species. Fil: Cano, Leonardo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Cagnoli, María V.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina Fil: Bengoa, José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina Fil: Marchetti, Sergio Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina

Some inorganic species of arsenic (As) present in drinking waters are highly dangerous for human health. Adsorption technique is considered a promising technology for the selective removal of As from aqueous systems. Iron (Fe), and iron-containing clays are adsorbents commonly used for arsenic elimination from water due to the strong affinity between Fe and inorganic species of As. Natural and acid-treated kaolinites, impregnated with iron oxides (30 % and 20 % of the Fe (III)) were developed in the present work. The selected clays were physico-chemically characterised, and the As adsorption capability was tested in batch experiments at pH = 7. Arsenic removal studies showed 97% effectiveness for the 30% iron sedimented kaolinite at 1 h of treatment, being the most effective developed material. These preliminary results showed that the Fe (III) impregnated kaolinites could be considered as promising adsorbent materials for As removal from aqueous systems.

Demostramos la existencia y ortogonalidad de operadores de onda naturalmente asociados a un Laplaciano compatible sobre una variedad completa con una esquina de codimensión 2. De hecho, probamos su completitud asintótica, es decir que la imagen de esos operadores de onda es igual al espacio de estados absolutamente contínuos del Laplaciano compatible. Logramos esto último usando metodos dependientes del tiempo que provienen del estudio de operadores de Schrödinger de varios cuerpos.

A key aspect of pilot-based grid operations are the GlideinWMS pilot factories. A proper and efficient use of any central block in the grid infrastructure for operations is inevitable, and GlideinWMS factories are no exception. The monitoring package for the GlideinWMS factory was originally developed when the factories were serving a couple of VOs and tens of sites. Today with the factories serving tens of VOs and hundreds of sites around the globe an update of the monitoring is due. Moreover with the new availability of industry open source storage and graphing packages an opportunity remains open.This work presents the changes made to the factory monitoring to leverage different technologies: Elasticsearch, RabbitMQ, Grafana, and InfluxDB to provide a centralized view of the status and work of several GlideinWMS factories located in different continents around the globe.

After embedding hematite nanowires (15 wt.% Fe) into a MCM-41 hard template, we have explored alternative routes to induce the structural transformations that lead from hematite to maghemite and magnetite embedded nanowires. The impregnation media (ethanol or water) and the calcination atmosphere (air and NO/He) on the hematite nanowires production play a significant role at the time of reducing and re-oxidizing the embedded hematite nanoparticles. The solids were characterized by X-ray diffraction, nitrogen adsorption, and Mossbauer spectroscopy. The results indicate that the effect of the solvent on the structural properties of the iron species is more important than the calcination atmosphere. The best conditions for iron magnetic nanowires not to get outside of the MCM-41 channels over the treatments are reached using water as the solvent and air as the calcination atmosphere. When ethanol is the solvent used over the preparation step, the end iron oxides are in the form of nanotubes spread out on the amorphous silica walls of the matrix.

An iron catalyst supported on SBA-15 was prepared and activated in H2 stream and in synthesis gas (H2:CO = 2:1) stream, in order to be used in the Fischer–Tropsch Synthesis. The different activation treatments led to different Fe species in fresh catalysts: a-Fe, Fe3O4 and Fe2+ diffused into the SBA-15 walls in H2-Fe/SBA-15 and v-Fe5C2, Fe3O4 and Fe2+ in H2:CO–Fe/SBA-15. These initial differences in the ‘‘bulk’’ structure of the solids disappear when both catalysts are ‘‘working’’. However, a higher production of total hydrocarbons, higher CO conversion and more CH4 and light gases were obtained for H2-Fe/SBA- 15 over 6 days. Besides, a higher selectivity toward light olefins was obtained with H2 Fe/SBA-15 during the first 24 h on reaction stream, but this selectivity decreases with the reaction time. These results are explained considering that the iron carbides produced from a-Fe are more active and/or have smaller sizes than that obtained from a-Fe2O3. Fil: Cano, Leonardo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina Fil: Cagnoli, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina Fil: Bengoa, Jose Fernando. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina Fil: Alvarez, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina Fil: Marchetti, Sergio Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina

In order to analyze the influence of the crystal size of the active phase in the Fischer-Tropsch synthesis (FTS), two iron catalysts, supported on MCM-41 and SBA-15, were prepared by incipient wetness impregnation and tested in this reaction. The solids were characterized by atomic absorption spectroscopy, N 2 adsorption, X-ray diffraction at low angles and Mossbauer spectroscopy. The activated catalysts showed the same iron species. However, the average crystal size of the active phase is about three times higher in SBA-15 than in MCM-41. Besides, both systems displayed a narrow size distribution. The catalyst with higher crystal size (Fe/SBA-15) presented higher conversion, higher chain growth and lower CH 4 production. These results would indicate that the FTS is a “structure sensitive” reaction in a sizes range within, approximately, 3–10 nm.

Levels established in water quality guidelines for the protection of aquatic life are based on the total concentrations of heavy metals regardless of speciation. However, there are numerous studies that show the importance of determining both the physicochemical characterisation of water body and the total concentration of heavy metals in them, including its chemical speciation, given its specific correlation with the bioavailability. In this regard, the objective of this study is to quantify concentrations of heavy metals in Los Patos lagoon, Argentina, and to show the utility of estimating with Visual MINTEQ software the fractions in which these metals are forming aqueous inorganic species or complexed with organic matter. The results demonstrate the relevance of using speciation calculations of metal cations, particularly when their concentrations are in the order of guide levels., Centro de Investigaciones del Medioambiente

Two Fe/MCM-41 systems, one of them sylilated, were obtained to be used as catalysts in Fischer–Tropsch reaction. They have more than 90% of the iron species located inside the support channels, leading to a narrow crystal size distribution accessible to reactive gases. The samples were characterized by X-ray diffraction, atomic absorption spectroscopy, N2 adsorption, Mossbauer spectroscopy and Fourier transformer infrared spectroscopy. Mossbauer spectroscopy allowed us to demonstrate that the catalytic active species were the same in both catalysts. The only difference between them was the surface hydrophobicity, which decreases the “water gas shift reaction” in the sylilated catalyst. Besides, this solid is more active for hydrocarbon production, with a lower methane yield.

The influence of the impregnation media (ethanol or water) and the calcination atmosphere (air and NO/He) on the hematite nanowires production embedded on a hard template (MCM-41) was studied. The solids were characterized by X-ray diffraction, Mössbauer spectroscopy and magnetic measurements. The results obtained indicate that the more appropriate conditions for the iron oxide nanowires to get inside the MCM-41 hard template seem to be reached using water as a solvent and air as calcination atmosphere. Fil: Cano, Leonardo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; Argentina Fil: Bengoa, Jose Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; Argentina Fil: Stewart, Silvana Jacqueline. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina Fil: Mercader, Roberto Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina Fil: Marchetti, Sergio Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; Argentina

Monodisperse iron oxide nanoparticles (NPs) of 4 nm were obtained through high-temperature solution phase reaction of iron (III) acetylacetonate with 1, 2-hexadecanediol in the presence of oleic acid and oleylamine. The as-synthesized iron oxide nanoparticles have been characterized by X-ray diffraction, transmission electron microscopy, Mössbauer spectroscopy and magnetic measurements. The species obtained were Fe3O4 and/or γγ -Fe2O3. These NPs are superparamagnetic at room temperature and even though the reduced particle size they show a high saturation magnetization (MS ≈ 90 emu/g). Fil: Cano, Leonardo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina. Universidad Nacional de La Plata; Argentina Fil: Cagnoli, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina. Universidad Nacional de La Plata; Argentina Fil: Stewart, Silvana Jacqueline. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Física La Plata; Argentina. Universidad Nacional de La Plata; Argentina Fil: Cabanillas, Edgardo Domingo. Comision Nacional de Energia Atomica; Argentina Fil: Romero, E. L.. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnologia; Argentina Fil: Marchetti, Sergio Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina. Universidad Nacional de La Plata; Argentina

This paper is devoted to the crumpling of thin matter. The Edwards-like statistical mechanics of crumpling networks in a crushed self-avoiding sheet with finite bending rigidity is developed. The statistical distribution of crease lengths is derived. The relationship between sheet packing density and hydrostatic pressure is established. The entropic contribution to the crumpling network rigidity is outlined. The effects of plastic deformations and sheet self-contacts on crumpling mechanics are discussed. Theoretical predictions are in good agreement with available experimental data and results of numerical simulations. Thus, the findings of this work provide further insight into the physics of crumpling and mechanical properties of crumpled soft matter.

Long-term evolution of residual hydronephrosis after successful pyeloplasty is not common. In this report, we have studied new ultrasound parameters, and have investigated the frequency of residual hydronephrosis. We highlight alternative radiation-free monitoring of pediatric pyeloplasties with ultrasound alone.Children who had undergone successful open Anderson-Hynes pyeloplasties in the period 2001-2010 were followed up. Exclusion criteria included non-clearly obstructed renography scans (tracer clearance half-time 20 min), crossing vessels, failed pyeloplasty, bilateral disease, other renal concomitant anomaly, absence of ultrasound measurements, and loss to follow up (1 year). Postoperative (postoperative) ultrasound parameters were anteroposterior (AP) diameter, pelvis-cortex (P/C) ratio, a proportion that takes in account these two values, enhancing sensitivity to evaluate minimal evolutive changes), and percentage of improvement (PI) in AP diameter (which reflects in relative means the evolution of each AP diameter, being 0% no change, and 100% absence of hydronephrosis) (Figure). Echographic checks were made at 3 and 6 months postoperatively and then yearly afterwards. SPSS software (v. 17.0 IBM, College Station, TX, USA) was used.Out of 80 pyeloplasties performed in the above-mentioned period, 44 patients (i.e., 44 renal units) fulfilled the inclusion criteria for the main study. The median age at time of operation was 15 months (range 2 months-10.3 years). The median follow-up was 4.5 years (range 1-12 years). The mean preoperative anteroposterior diameter was 26 mm (range 16-54 mm). At the third postoperative check, the mean the PI was 29%, and rose to 53% at 6 months (p=0.027). Posterior controls showed a stable yearly PI during follow-up, without statistically significant variations (40-59% in subsequent years, p0.5). The P/C ratio had already downgraded significantly at the third postoperative check (4.6 preoperative vs. 1.8 postoperative; p=0.03). A subgroup analysis of failed pyeloplasty (4 renal units) showed all PI 15% at the third postoperative month (sensitivity 100%, specificity 86%). Complete resolution of hydronephrosis occurred in nine patients (20%).The P/C ratio and PI are new feasible ultrasound parameters in pyeloplasty follow-up. Early improvement in the P/C ratio can be expected and might avoid repeated ionizing scans. A PI15% in subsequent postoperative checks might be enough for safe monitoring with ultrasound alone. Thus, renograms may be solicited only in these cases where ultrasound parameters do not improve in the first 6 postoperative months. Afterwards, ultrasound parameters often remain stable in the long term. Absence of hydronephrosis could only be documented in the long term in one out of every five patients.

We apply Mourre theory to compatible Laplacians on manifolds with corners of codimension 2 in order to prove absence of singular spectrum, that non-threshold eigenvalues have finite multiplicity and could accumulate only at thresholds or infinity. It turns out that we need Mourre estimates on manifolds with cylindrical ends where the results are both expected and consequences of more general theorems. In any case we also provide a description, interesting in its own, of Mourre theory in such context that makes our text complete and suggests generalizations to higher order codimension corners. We use theorems of functional analysis that are suitable for these geometric applications., This paper has been withdrawn by the author in order to correct reference [3] respect to the $C^1(A)$-property

Retrocaval ureter is a rare disease which is due to a abnormal development of the inferior cava vein. It usually presents with ureteral obstruction, and surgery is needed for symptomatic cases.We present a case of retrocaval ureter and a revision of the literature.A 9 year-old boy who had consulted for macroscopic hematuria. The intravenous urography (IVU) suggested the diagnosis of retrocaval right ureter, which is confirmed by magnetic resonance imaging (MR). Make us resection of the retrocaval segment and relocation of the ureter anterior to the inferior vena cava. Follow-up IVU showed good resolution of hydronephrosis.Retrocaval ureter is a rare disease, with easy diagnostic and effective treatment. Other associated anomalies could be associated.

El proceso conocido como síntesis de Fischer-Tropsch permite realizar la síntesis catalítica de hidrocarburos a partir del denominado gas de síntesis (mezcla en relaciones determinadas de CO:H2). El gas de síntesis puede ser producido por gasificación de C o de biomasa y por reformado de CH4. En la síntesis se obtiene una mezcla compleja de hidrocarburos de cadena lineal y ramificada, así como también productos oxigenados como alcoholes, aldehídos, cetonas y ésteres, aunque los mayoritarios son parafinas lineales y α-olefinas. A través de un adecuado control de las condiciones operativas y de los tratamientos realizados “aguas abajo” del reactor de FischerTropsch es posible conseguir: alta producción de naftas, fuel oil de excelente calidad, α-olefinas lineales de alto valor agregado, etc. Además, desde un punto de vista ambiental, los diesel sintéticos producidos por Fischer-Tropsch tienen ciertos beneficios, entre ellos: contenido nulo de azufre, reducción de la emisión de material particulado, bajo contenido de aromáticos y relativamente alto número de cetano. Las condiciones operativas de la síntesis son muy variadas, se pueden utilizar presiones en el rango de 1 a 20 atm y temperaturas en el rango de 523 a 673 K. La elección de los valores óptimos de presión y temperatura tiene que ver con el catalizador usado y los productos que se quieran obtener, por ejemplo: presiones altas favorecen el crecimiento de cadena mientras temperaturas altas favorecen la producción de metano., Facultad de Ciencias Exactas

Monodisperse iron oxide nanoparticles (NPs) of 4 nm were obtained through high-temperature solution phase reaction of iron (III) acetylacetonate with 1, 2-hexadecanediol in the presence of oleic acid and oleylamine. The as-synthesized iron oxide nanoparticles have been characterized by X-ray diffraction, transmission electron microscopy, Mossbauer spectroscopy and magnetic measurements. The species obtained were Fe3O4 and/or \(\upgamma\)-Fe2O3. These NPs are superparamagnetic at room temperature and even though the reduced particle size they show a high saturation magnetization (MS ≈ 90 emu/g).

Iron catalysts, to be used in the Fischer–Tropsch reaction were prepared using zeolite LTL and zeolite LTL modified with cesium, as supports. X-ray diffraction, specific surface area, atomic emission and absorption spectroscopies, Mo¨ssbauer spectroscopy in controlled atmosphere, between room temperature and 22 K, H2 chemisorption and volumetric oxidation were used to characterize the solids. Comparing both catalysts, the Cs presence generates a solid with a lower reducibility degree and a lower quantity of Fe0 microcrystals inside the pore structure, leading to a lower activity per gram and a higher olefins/paraffins ratio. Fil: Gallegos, Norma Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; Argentina Fil: Alvarez, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; Argentina Fil: Cagnoli, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; Argentina Fil: Bengoa, Jose Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; Argentina Fil: Cano, Leonardo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; Argentina Fil: Mercader, Roberto Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina Fil: Marchetti, Sergio Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; Argentina