New analytical method for determination of phthalates in wastewater by on line lc-gc-ms using the totad interface and fraction collector

There is an increasing demand for automatic, reliable and sensitive analytical methods for determining trace levels of phthalic acid esters (PAEs) in environmental samples. While on line coupled liquid chromatography-gas chromatography (LC-GC) has been proof to be a powerful tool for trace-level analyses in complex matrices, the present work presents a new totally automated on line LC-GC method, using the Through Oven Transfer Adsorption Desorption (TOTAD) interface, for the analysis of four of the main phthalates, dibuthyl phthalate (DBP), diethyl phthalate (DEP), dimethyl phthalate (DMP) and diethylhexyl phthalate (DEHP), in a matrix as complex as leachate. The sample is directly injected into the LC injector valve with no sample pretreatment other than simple filtration. The LC step separates the target analytes from matrix interference. Two different LC fractions are collected in a purposely designed fraction collector and then transferred to the TOTAD interface, which concentrates the analytes, totally eliminates the solvent and transfers the analytes to the GC-MS system, where the analysis is carried out. The LOD of the method varied from 0.1 µg/L (DEHP) to 1.4 µg/L (DMP), RSD for retention time below 0.14% and for absolute peak areas below 12% and linearity from 1 µg/L to 1000 µg/L (R2 > 0.99), except in the case of DEHP (linearity from 1 to 250 µg/L, R2 = 0.94). The method was applied to the analysis of the target analytes in samples collected from a municipal solid waste (MSW) landfill in Rosario (Argentina).Fil: Espinosa, F.J.. Universidad de Castilla-La Mancha; EspañaFil: Toledano, R.M.. Universidad de Castilla-La Mancha; EspañaFil: Andini, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Cortés, J.M.. Universidad de Castilla-La Mancha; EspañaFil: Vázquez, A.M.. Universidad de Castilla-La Mancha; Españ

Learning and Forgetting with Local Information of New Objects

The performance of supervised learners depends on the presence of a relatively large labeled sample. This paper proposes an automatic ongoing learning system, which is able to incorporate new knowledge from the experience obtained when classifying new objects and correspondingly, to improve the efficiency of the system. We employ a stochastic rule for classifying and editing, along with a condensing algorithm based on local density to forget superfluous data (and control the sample size). The effectiveness of the algorithm is experimentally evaluated using a number of data sets taken from the UCI Machine Learning Database Repository

SOMPhotoLog. Arquitectura e imagen

La acción recíproca que se ejerce entre las partes de un edificio y la interacción entre la obra de arquitectura y su entorno inmediato, conforman un conjunto de vínculos. Este grupo de relaciones es posible plasmarlo a través de la fotografía, hallando en el material de los reportajes y colecciones fotográficas, la posibilidad de generar intencionadas muestras de imágenes en simultáneo. El SOMPhotoLog como grupo de fichas de registro de las fotografías de los proyectos de Skidmore, Owings & Merrill, nos permitirán recuperar el discurso visual del Union Carbide Building. Este edificio, emplazado en el Midtown de Manhattan, despliega diversas tácticas de orden visual en su encuentro con la ciudad, que hallarán en las series de imágenes su mejor y más completa expresión. Se busca hacer de estas fotos, fotogramas de un guión que nos aproxime a un cortometraje que entrelace: arquitectura, fotografía y ciudad. Se procura demostrar que la imagen entendida como medio, amplia su valor al atender al proceso de proyecto fotográfico y al mostrarse como ordenada urdimbre, compuesta por diversas escalas, que es y representa enlaces entre elementos y disciplinas. Los fotogramas de arquitectura moderna serán de Ezra Stoller, Joseph Molitor, George Cserna, Alex Langley, William Rivelli; y los de la ciudad a la que se incorporan, de William Klein. Este grupo de fotografías conformaran dos secuencias, correspondiendo al exterior e interior de la obra; y estarán acompañadas por tres intervalos de vida urbana que completarán la narrativa visual. Situar la mira en los lindes entre cosas urbanas será la condición que revele las cualidades de la fotografía como herramienta proyectual y de análisis en la creación de espacios. Estos paralelos visuales, acrecentarán el valor de las fotos, intensificando las relaciones entre ellas, ampliando su objetivo y emparentándolas con la del objeto de arquitectura y su lugar.The reciprocal action exerted between the parts of a building and the interaction between the architectural work and its immediate surroundings form a set of links. It is possible to capture this group of relationships through photography, finding in the material of the reports and photographic collections, the possibility to generate deliberate image samples simultaneously. The SOMPhotoLog as a group of registration cards of photographs of projects from Skidmore, Owings & Merrill, will allow us to recover the visual discourse of Union Carbide Building. This building, located in Midtown Manhattan, deploys various visual tactics in its encounter with the city, which will find in the image series its best and most complete expression. It is sought to make these photos, photograms from a script that approximates us to a short film that interlaces architecture and photography with the city. It is aimed to show that the image understood as a mean, expands its value when attends the photographic project process and appears as an ordered warp, composed of various scales, which is and represents links between elements and disciplines. Modern architecture photograms are from Ezra Stoller, Joseph Molitor, George Cserna, Alex Langley, William Rivelli; and those from the city where they incorporate from William Klein. This group of photographs shapes two sequences, corresponding to the exterior and interior of the work; and they will be accompanied by three intervals of urban life that will complete the visual narrative. To place sights on the borders between urban things is the condition that reveals the qualities of photography as a design and analysis tool for creating spaces. These visual parallels will increase the value of the photos, enhancing the relations between them, extending their objective and intermarrying them with the object of architecture and place

Estudio de aceptabilidad sensorial por parte de consumidores de gel fluorado saborizado de uso bucal

El propósito de este estudio es evaluar la aceptabilidad sensorial de dos formulaciones de gel con fluoruro de sodio, que difieren en el aromatizante utilizado (A –fórmula original- y B –nuevo sabor-) mediante el uso de una escala hedónica. Las diferencias significativas se analizaron mediante un test no paramétrico de la mediana con un nivel de significancia del 5%. No hubo diferencias significativas en los atributos olor, aspecto y consistencia y persistencia olfato gustativa, mientras que hubo diferencias significativas en los atributos sabor y color, siendo la muestra A la que obtuvo el promedio más alto de aceptación para todos los atributos. Si bien el proceso farmacotécnico utilizado para la elaboración de los dos productos fue el mismo, y los colorantes utilizados los mismos, la diferencia encontrada en el atributo color se explica por una asociación subjetiva entre sabor y color.The purpose of this study is to evaluate the sensory acceptability of two formulations of the gel which differ in the flavoring used (A -original formula- and B -new flavour-). Significant differences were analyzed using a nonparametric median test with a significance level of 5%. Were no significant differences in odor, appearance and consistency, and smell-taste persistence attributes, whereas significant differences were observed in taste and color attributes, being the sample A to which was the highest rate of acceptance for all attributes. Although the pharmacotechnical process used to produce both products and the colorants used was the same, the differences found in the color attribute may be explained by a subjective association between taste and color..Este trabajo ha sido financiado por la Secretaria de Investigación de la Universidad Católica de Córdoba (Argentina)

Efecto de la música sobre la ansiedad y el dolor en pacientes con ventilación mecánica

La capacidad de la música para aliviar la ansiedad o el dolor ha sido utilizada ampliamente a lo largo de la historia. Objetivo: Examinar los efectos de la música sobre la ansiedad y el dolor en pacientes con ventilación mecánica invasiva. Diseño: Un ensayo aleatorizado controlado con medidas repetidas. Material y método: estudio prospectivo experimental con distribución aleatoria, en un hospital universitario de tercer nivel, de enero de 2009 a junio de 2010. La muestra fue de 44 participantes. La intervención consistió en una sesión musical de 30 min, con auriculares, en habitación individual. Al grupo control se le mantuvo sin ningún cambio en el entorno habitual de una unidad de cuidados intensivos. A cada paciente se le realizaron un mínimo de 3 y un máximo de 5 sesiones musicales. La música fue escogida por el paciente entre una selección musical preparada por el equipo investigador. La ansiedad, el dolor y las variables hemodinámicas frecuencia cardiaca, frecuencia respiratoria, tensión arterial sistólica y diastólica se midieron en el momento basal, tras la sesión musical y una hora después de la audición musical. Resultados: La musicoterapia disminuyó significativamente la ansiedad (p = 0,000), medida con la escala de Ansiedad Estado-Rasgo (STAI). No hubo diferencia significativa en los niveles de dolor (p = 0,157), medida con la escala visual analógica. No se demostró efecto sumativo a lo largo de las múltiples sesiones. Conclusión: La música reduce la ansiedad en los pacientes con ventilación mecánica invasiva, pudiéndose establecer como una herramienta no farmacológica a añadir a las opciones terapéuticas de las cuales disponemos

Influence of the pavement surface on the vibrations induced by heavy traffic in road bridges

The irregularity of the pavement surface governs the traffic-induced vibrations in road bridges, but it is either ignored or simulated by means of ideal pavements that differ significantly from real cases. This work presents a detailed dynamic analysis of a heavy truck crossing a 40-m span composite deck bridge using on-site measurements of different existing road profiles, as well as code-based ideal pavements. By activating or deactivating certain spatial frequency bands of the pavement, it is observed that the ranges 0.2 - 1 and 0.02 - 0.2 cycles/m are critical for the comfort of the pedestrians and the vehicle users, respectively. Well maintained roads with low values of the displacement Power Spectral Density (PSD) associated with these spatial frequency ranges could reduce significantly the vibration on the sidewalks and, specially, in the vehicle cabin. Finally, a consistent road categorisation for vibration assessment based on the PSD of the pavement irregularity evaluated at the dominant frequencies is proposed

Quantum effective actions from nonperturbative worldline dynamics

We demonstrate the feasibility of a nonperturbative analysis of quantum field theory in the worldline formalism with the help of an efficient numerical algorithm. In particular, we compute the effective action for a super-renormalizable field theory with cubic scalar interaction in four dimensions in quenched approximation (small-$N_f$ expansion) to all orders in the coupling. We observe that nonperturbative effects exert a strong influence on the infrared behavior, rendering the massless limit well defined in contrast to the perturbative expectation. Our numerical method is based on a direct use of probability distributions for worldline ensembles, preserves all Euclidean spacetime symmetries, and thus represents a new nonperturbative tool for an investigation of continuum quantum field theory.Comment: 33 pages, 10 figure

Characteristics of ripened Tronchon cheese from raw goat milk containing legally admissible amounts of antibiotics

[EN] The aim of this study was to evaluate the transfer of the most widely used antibiotics in dairy goats from milk to cheese as well as their effect on the cheese-making process and cheese characteristics during ripening. Antibiotic-free milk was spiked individually with 7 veterinary drugs (amoxicillin, benzylpenicillin, cloxacillin, erythromycin, ciprofloxacin, enrofloxacin, and oxytetracycline) at an equivalent concentration of the European Union maximum residue limit. Spiked goat milk was used to make mature Tronchon cheeses, which were analyzed at 0, 30, and 60 d of maturation to determine pH, chemical composition, proteolytic and lipolytic activities, and color and textural properties. A sensory evaluation of 60-d ripened cheeses was carried out. Cheeses from raw antibiotic-free goat milk were made simultaneously to be used as reference. The cheese-making process was unaffected by the presence of most antibiotics evaluated. Only erythromycin and oxytetracycline significantly increased the time required for cheese production (122 +/- 29 and 108 +/- 25 min, respectively). However, variable amounts of antibiotics, ranging from 7.4 to 68%, were transferred from milk to cheese, with oxytetracycline and quinolones showing the highest retention rates. In general, antibiotic residues present in the cheeses at the beginning of maturation decrease significantly along time. Thus, beta-lactams and erythromycin residues were not detectable after 30 d of ripening. However, relatively high concentrations of enrofloxacin (148 +/- 12 mu g/kg) and ciprofloxacin (253 +/- 24 mu g/kg) residues were found in the cheeses after 60 d of maturation. The quality characteristics of the Tronchon cheeses were only slightly affected by such substances, with few significant differences in the free fatty acid concentration and color and textural properties of the cheeses. Results herein indicate that the use of goat milk containing antibiotics, such as quinolones, at the European Union maximum residue limit for cheese production could adversely affect the safety of the final products because relatively high concentrations of these substances could be retained in soft and semi-mature cheeses, making it necessary to assess the risk for consumer health. Studies on the partition of the antibiotic substances during cheese-making, using specific technologies, would be convenient to guarantee the safety of cheese and related products.This work is part of the AGL-2013-45147-R Project funded by Ministerio de Ciencia e Innovación (Madrid, Spain). P. Quintanilla thanks Universitat Politècnica de València (Valencia, Spain) for the grant received for the development of this work (PAID-2014, UPV).Quintanilla-Vázquez, PG.; Beltrán Martínez, MC.; Molina Casanova, A.; Escriche Roberto, MI.; Molina Pons, MP. (2019). Characteristics of ripened Tronchon cheese from raw goat milk containing legally admissible amounts of antibiotics. Journal of Dairy Science. 102(4):2941-2953. https://doi.org/10.3168/jds.2018-15532S29412953102

Diffusion in supersonic, turbulent, compressible flows

We investigate diffusion in supersonic, turbulent, compressible flows. Supersonic turbulence can be characterized as network of interacting shocks. We consider flows with different rms Mach numbers and where energy necessary to maintain dynamical equilibrium is inserted at different spatial scales. We find that turbulent transport exhibits super-diffusive behavior due to induced bulk motions. In a comoving reference frame, however, diffusion behaves normal and can be described by mixing length theory extended into the supersonic regime.Comment: 11 pages, incl. 5 figures, accepted for publication in Physical Review E (a high-resolution version is available at http://www.aip.de./~ralf/Publications/p21.abstract.html