Reaction kinetics of bacteria disinfection employing hydrogen peroxide Labas, Marisol Daniela; Zalazar, Cristina Susana; Brandi, Rodolfo Juan; Cassano, Alberto Enrique The inactivation reaction of Escherichia coli bacteria employing hydrogen peroxide at 20 ºC and pH = 7 was studied in a well-mixed batch reactor. The proposed objective, as far as the extent of inactivation is concerned, was obtained for H2O2 concentrations above 100 ppm (1 ppm = 2.94×10-5 mmol cm-3) but, compared with other disinfection technologies, for too long reaction times. Below 40 ppm of the oxidant concentration inactivation was practically ineffective. Results were analyzed employing Modified forms of the Series-Event and Multitarget mechanistic models. At concentrations above 100 ppm the induction time in the semi-logarithmic plot of bacteria concentration versus time was reduced. With both modified models it was found that the reaction order with respect to the hydrogen peroxide concentration was different than one. Both mathematical descriptions provide a good representation of the experimental results in an ample range of the disinfectant concentrations and confirm a methodology that renders the starting point of a reaction kinetic expression useful for further studies regarding the optimization of the operating conditions (pH and temperature, for example), including also combination with other advanced oxidation technologies. An interpretation of the data in terms of a Weibull-like model [1] is also included.

Hydration, charge, size, and shape characteristics of peptides from their CZE analyses Peirotti, Marta Beatriz; Piaggio, María Virginia; Deiber, Julio Alcides A capillary zone electrophoresis model is presented for peptide characterization, on the base of well established physicochemical equations.The effective mobility is used as basic data in the model to estimate relevant peptide properties like, for instance, hydration, net and total electrical charge numbers, hydrodynamic size and shape, particle average orientation, and pH-microenvironment from the charge regulation phenomenon. Therefore 102 experimental effective mobilities of different peptides are studied and discussed in relation to previous works. An equation for the estimation of peptide hydration as a function of ionizing, polar and non polar amino acid residues is included in the model. It is also shown that the shape-orientation factor of peptides may be either lower or higher than one, and its value depends on a complex interplay among mainly charge number, molar mass, hydration and amino acid sequence.

In,Fe-Zeolites: active and stable catalysts for the SCR of NOx. Kinetics, characterization and deactivation studies Serra, Ramiro Marcelo; Vecchietti, María Julia; Miro, Eduardo Ernesto; Boix, Alicia Viviana In this work, the addition of Fe2O3 to InH-zeolites (ZSM5 and mordenite) is investigated for the selective catalytic reduction of NOx with both methane and butane as reducing agents. When Fe is added to InHMOR and methane is used, the NOx to N2 conversion increases from 25% to 55% at 20,000 h-1 and 500 8C. An increase is also observed when butane is employed but to a lower extent. The role of Fe could be ascribed to an improvement of the NO to NO2 reaction rate. The presence of iron oxides also improves durability in the presence of 2% water. The catalyst InFeHMOR undergoes a fast initial inhibition after which a reasonable NOx conversion (25%) remains constant during 125 h. TPR, XRD and LRS characterizations indicate that Fe2O3 and Fe3O4 are the iron species present, while InO+ at exchange sites and small amounts of In2O3 are also present. The kinetic plots for the NOx selective catalytic reduction (SCR) with methane with the InFeHMOR catalyst show fractional orders for the NO concentration and ca. first order for methane.

High-energy emission from accreting black holes with high-mass donor stars Vila, Gabriela Soledad; Romero, Gustavo Esteban We present an analysis of the interactions of a distribution of relativistic protons under the typical conditions of the corona surrounding an accreting black hole. The model is applied to a concrete binary system with a high-mass donor star: the classical source Cygnus X-1

HDE 269896: una supergigante especial de la nube mayor de Magallanes Corti, Mariela Alejandra; Walborn, Nolan Revere The star HDE 269896, a hypergiant in the Large Magellanic Cloud, with spectral type ON9.7 Ia+, is a special case within the known OB Zoo. We have discovered strong emission from the N II 5000 ˚A complex in its spectrum, and the previously known He II λ4686 emission, with an anomalous strength for the spectral type, has also been observed. Comparing HDE 269896 with other objects that show N II emission lines, such as WN10 and WN11 types, we find that this star is highly evolved, albeit less so than the latter stars. Thus, it is reasonable to propose that HDE 269896 should be in an immediate pre-WNVL (Very Late WN) state. Another characteristic of this star is the unusually wide range of ionization present in its extended atmosphere. Subsequent analysis of its spectrum will permit a better understanding of both the relevant atomic physics and the structure of this unusual atmosphere.; La estrella HDE 269896, hipergigante de la Nube Mayor de Magallanes, con tipo espectral ON9.7 Ia+, es un caso particular dentro del zoológico OB conocido. Hemos encontrado en su espectro, una intensa emisión del complejo N II 5000 A y se ha observado también una emisión ˚ de He II λ4686, la cual por su intensidad, resulta anómala para su tipo espectral. Comparando a HDE 269896 con otros objetos que muestran líneas de emisión de N II, como ser WN10 y WN11, resulta evidente que HDE 269896 es un objeto altamente evolucionado, aunque lo es menos que las estrellas WN10 y WN11. Por esto, resulta razonable proponer que HDE 269896 debe hallarse en un estado inmediato de pre-WNVL (Very Late WN). Otra particularidad presente en HDE 269896, es el inusualmente amplio rango de ionización que tiene lugar en su atmósfera extendida. Análisis posteriores de su espectro permitirán comprender mejor tanto la física atómica involucrada como la estructura de esta atmósfera inusual.

La génesis de los Universales en Prasastapada y la génesis de los Principia Prima y los Universales en Aristóteles Tola, Fernando; Dragonetti, Carmen Leonor En este artículo los autores ofrecen un nuevo caso en soporte de su tesis concerniente a las frecuentes coincidencias temáticas en las Filosofías de la India y de Occidente, que ellos han desarrollado en especial en sus libros On the Myth of the Opposition between Indian Thought and Western Philosophy, Hildesheim: Olms Verlag, 2004, reseñado por Ernst Steinkellner en Wiener Zeitschrift für die Kunde Südasiens Band XLVIII 2004, 224-225, y Yoga. Un Camino Místico Universal, Barcelona: Editorial Kairós, 2006. Dicha tesis apunta a lo que podríamos llamar una suerte de globalidad intrínseca del pensar filosófico, más allá de la cultura de que se trate. Praastapda (circa segunda mitad del siglo VII d.C.), en Praastapdabh=ya (llamado también Padrthadharmas{graha), Libro V: Smnyapadrthanirpaa, da dos descripciones de la génesis de los universales. Describe primeramente de una manera abstracta y concisa el proceso de surgimiento de todo smnya, “universal”, y después explica de una manera más concreta el surgimiento del universal inferior y del superior (satt, “la existencia”), a través de la reiteración de la percepción de objetos que presentan similares atributos y de la intervención del recuerdo de percepciones similares pasadas. Aristóteles (siglo IV a.C.), en Analytica Posteriora, Libro II, Capítulo XIX, y Temistio (circa 317-circa 387), en su comentario, explican a su vez el modo en que son aprehendidos los principios universales o premisas de la demostración (principia prima). Los autores de este artículo muestran cómo la descripción de Aristóteles y Temistio de la génesis de los principia prima y los universales concuerda de manera sorprendente con la de Praastapda concerniente a los universales.

Effect of iron on the properties of sulfated zirconia Costa Pereira, Amalia Luz; Marchetti, Sergio Gustavo; Albornoz, Alberto; Reyes , Patricio; Oportus, Marcelo; Rangel. Maria do Carmo Sulfated zirconia has found several industrial applications, mainly for catalyzing reactions which require acidic sites. In order to control the properties of this solid, the effect of iron on the sulfated zirconia properties was studied in this work. Samples with different iron to zirconium molar ratios were prepared by the sol–gel method, followed by sulfation and characterization by several techniques. It was found that all iron ions go into zirconia when Fe/Zr 0.4. However, when higher amounts of iron (Fe/Zr 0.8) are added, hematite is segregated. Different phases can be obtained depending on the iron content and on the sulfur presence. Iron increases the specific surface areas of both sulfated and pure zirconia but does not affect the incorporation of sulfate groups as compared to pure zirconia. Iron also makes the solids thermally more stable and modifies the sulfated zirconia surface creating acidic sites with medium strength. Therefore, it is possible to control the acidity of the solid doping the sulfated zirconia with iron. All these changes are very useful for catalytic applications.

Q-spaces and the foundations of quantum mechanics Domenech, Graciela; Holik, Federico Hernan; Krause, Décio Our aim in this paper is to take quite seriously Heinz Post’s claim that the non-individuality and the indiscernibility of quantum objects should be introduced right at the start, and not made a posteriori by introducing symmetry conditions. Using a different mathematical framework, namely, quasi-set theory, we avoid working within a labeltensor-product-vector-space-formalism, to use Redhead and Teller’s words, and get a more intuitive way of dealing with the formalism of quantum mechanics, although the underlying logic should be modified. Thus, this paper can be regarded as a tentative to follow and enlarge Heinsenberg’s suggestion that new phenomena require the formation of a new “closed” (that is, axiomatic) theory, coping also with the physical theory’s underlying logic and mathematics.

A topological study of contextuality and modality in quantum mechanics Domenech, Graciela; Freytes Solari, Hector Carlos; de Ronde, Christian Kochen-Specker theorem rules out the non-contextual assignment of values to physical magnitudes. Here we enrich the usual orthomodular structure of quantum mechanical propositions with modal operators. This enlargement allows to refer consistently to actual and possible properties of the system. By means of a topological argument, more precisely in terms of the existence of sections of sheaves, we give an extended version of Kochen-Specker theorem over this new structure. This allows us to prove that contextuality remains a central feature even in the enriched propositional system.

Larnax altomayoense y Larnax chotanae (Solanaceae) dos nuevas especies de los bosques montanos del Norte del Perú; Larnax altomayoense y Larnax chotanae (Solanaceae) two new species from montane forests of Northern Peru Leiva González, Segundo; Pereyra Villanueva, Erwin; Barboza, Gloria Estela Se describen Larnax altomayoense y Larnax chotanae (Solanaceae) dos nuevas especies de los Bosques Montanos del Norte del Perú. Larnax altomayoense S. Leiva & Quipuscoa propia del Bosque de Protección del Alto Mayo, ruta entre el poblado de Aguas Verdes-Santa Rosa del Alto Mayo, Prov. Rioja, Dpto. San Martín, Perú, entre los 980-1010 m de elevación, se caracteriza por las flores 1-2 por nudo, cáliz rodeado por una cobertura de pelos glandulares transparentes externa e interiormente, corola campanuladaestrellada, glabra externa e interiormente, lóbulos corolinos lila-intenso cerca del 90% del área central con los bordes verdoamarillentos, lustrosos interiormente, filamentos estaminales homodínamos, cremosos, anteras morado-intenso, ovario con algunas pintas lilas longitudinales en la mitad distal, estilo exerto, baya cónica, semillas 88-95 por baya, arbustos de (0,70-) 1,20-1,50 m de alto y Larnax chotanae S. Leiva, Pereyra & Barboza habita en el bosque El Pargo (ruta Llama-Huambos), Prov. Chota, Dpto. Cajamarca, Perú, alrededor de los 3050 m de elevación, presenta las flores (2-) 3-4 por nudo, corola campanulada-estrellada, amarillo externamente, verdoso interiormente, limbo de 12-14 mm de diámetro en la antésis, estambres exertos, filamentos estaminales homodínamos, amarillos, anteras moradas, estilo exerto, amarillento, baya cónica amarillento-anaranjada, semillas 22-49 por baya, esclerosomas 12- 14 por baya, arbustos de 1,20-1,50 m de alto. Adicionalmente a las descripciones se presentan las ilustraciones correspondientes, se discuten sus relaciones con otras especies afines e incluyen datos sobre su distribución geográfica, ecología y situación actual.

Analysis of sequence configurations of the PKR-interacting HCV proteins from plasma and PBMC as predictors of response to interferon-alpha and ribavirin therapy in HIV-coinfected patients Bolcic, Federico Martin; Bull, L.; Martinez, L.; Reynoso, Rita Paola; Salomon, H.; Arduino, R.; Barnett, B.; Quarleri, Jorge Fabian Antecedentes: El tratamiento basado en interferon es una terapia estándar contra la hepatitis C crónica en pacientes coinfectados con el VIH. Exploramos el rol de dos regiones genómicas del HCV en la respuesta al IFN entre los pacientes coinfectados HIV-HCV. A través de una cohorte homogénea retrospectiva, evaluamos la frecuencia de las mutaciones E2 y NS5A en pacientes con y sin respuesta viral sostenia a la terapia basada en IFN. Métodos: Se individualizaron restrospectivamente las muestras de una cohorte homogenea de 10 pacientes coinfectados con HCV-VIH que completaron la terapia con IFN. Todos los pacientes estaban bajo tratamiento con la terapia HAART. El genotipo del HCV (basado en 5?NCR+NS5B relacionado filogenéticamente) y los análisis genómicos E2/NS5A se realizaron en compartimentos con muestras de suero y PBMC. Se analizaron las mutaciones carboxiterminales de E2, incluyendo el dominio homólogo de fosforilación PKR/eIF2alfa (PePhD) y las mutaciones de dominio unidas a la proteina kinasa de 5A no estructurado (PKRBD). Resultados: Cuatro pacientes lograron una respuesta viral sostenida y 6 fueron no respondedores (NR). Entre los pacientes con respuesta viral sostenida, los genotipos eran Gt-1 (n=3) y Gt4 (n=1).  Los tratamientos fallados fueron infectados con el Gt-1 (n=5) y el Gt-2 (n=1). La distribución genotípica fue igual para ambos grupos, los que obtuvieron respuesta viral sostenida y los no respondedores (p>0.05). Entre los compartimentos, el número de mutaciones en PKRBD fue conservado, mientras que el número de mutaciones de dominio PePHD fueron significativamente menores. Los pacientes NR exhibieron casi el mismo número de mutaciones en ambos compartimentos, mientras que aquellos con respuesta viral sostenida solo demostraron mutaciones en aislados del HCV en plasma. Cuando se realizó una comparación entre pacientes, la distribución de mutación cuantitativa o cualitativa entre los compartimentos de plasma y PBMC de cada región genómica se halló que era casi similar. Conclusiones: La frecuencia de mutaciones en las regiones definidas de la envoltura 2 del HCV PePHD y la proteina 5A no estructurada (NS5A) parece no influenciar la capacidad de IFN-alfa para bloquear la replicación del HCV ni tampoco predecir fehacientemente el resultado del tratamiento en pacientes coinfectados con VIH/HCV.

Chitosan influence on glucose and calcium availability from yogurt: In vitro comparative study with plants fibre Rodriguez, Maria Susana; Montero, Mirta Ester; Dello Staffolo, Marina; Martino, Miriam Nora; Bevilacqua, Alicia Eva; Albertengo, Liliana Since chitosan complies with the definition of dietary fibre is necessary to study the interaction of this biopolymer with nutrients. Yogurt with fortified chitosan and different types of plants fibres like wheat, bamboo, apple, psyllium and inulin was used as a food model. The availabilities of glucose and calcium in this model were studied by an in vitro gastrointestinal tract simulation. Results showed that the different fibres decreased both glucose and calcium availabilities whereas the effect of chitosan was more pronounced. (17.7 ± 2.1% and 21.0 ± 2.5% depress respectively). This work demonstrated that the addition of chitosan to yogurts influences the availability of nutrients.

Nonequilibrium critical dynamics of the three-dimensional gauge glass Romá, Federico José; Domínguez, Daniel We study the nonequilibrium aging behavior of the gauge glass model in three dimensions at the critical temperature. We perform Monte Carlo simulations with a Metropolis update, and correlation and response functions are calculated for different waiting times. We obtain a multiplicative aging scaling of the correlation and response functions, calculating the aging exponent b and the nonequilibrium autocorrelation decay exponent λc/z c. We also analyze the fluctuation-dissipation relationship at the critical temperature, obtaining the critical fluctuation-dissipation ratio X∞. By comparing our results with the aging scaling reported previously for a model of interacting flux lines in the vortex-glass regime, we found that the exponents for both models are very different.

Regulation of testosterone degradation in Comamonas testosteroni Linares, Mauricio Adrián; Pruneda Paz, Jose Luis Pablo; Reyna, Luciana; Genti de Raimondi, Susana Recently, we have identified a gene encoding a LuxR-type factor, TeiR (Testosterone-inducible Regulator), which positively regulates steroid degradation in Comamonas testosteroni. Herein, we demonstrate that TeiR interacts in vivo with steroid catabolic gene promoters. The presence of testosterone induces a significant TeiR protein increase at the early logarithmic phase of growth. Interestingly, it is not until the early stationary phase where the activation of a steroid-inducible gene promoter is observed, indicating that testosterone might not be the true inductor of the steroid degradation pathway. In addition, β-galactosidase expression driven by a testosterone-inducible promoter is prematurely activated in cells cultured in medium supplemented with ethyl acetate extracts obtained from the early stationary phase cell-free supernatants of C. testosteroni grown in presence of testosterone. Complementation experiments of C. testosteroni wild type performed with teiR deletion constructs indicate that extra-copies of deleted-TeiR exert a dominant negative effect on the wild-type TeiR protein. While, when C. testosteroni teiR mutants were used to carry out complementation assays only the full length gene can overcome the teiR mutant phenotype. Altogether these findings indicate that TeiR regulates steroid catabolic genes interacting with their promoters and suggest that this interaction requires the presence of a testosterone-derived metabolite to induce the system.

Self-monitoring of blood glucose in type 2 diabetes: an inter-country comparison Davis, W. A.; Bot, S.; Davis, T. M. E.; Farmer, A.; Gagliardino, Juan Jose; Giorda, C.; Home, P. D.; Jermendy, G.; Ji, L.; Johnson, Jeff; Karter, A. J.; Kolb, H.; Martin, S.; Mohan, V.; Nicolucci, A.; Porta, M.; Ramachandran, A.; Ramaiya, K. L.; Shah, J. H.; Shera, A. S.; Skeie, S. Self-monitoring of blood glucose (SMBG) in type 2 diabetic patients was compared across 14 countries. There was an unexpectedly high SMBG-use in non-insulin-treated patients. Reimbursement polices differed by country, region, insurance status, and patient income. More rigorous and systematic data collection is needed to ensure evidence-based SMBG-use

Aplicación de redes neuronales artificiales para la predicción de calidad de aire Chiarvetto Peralta, Lucila Lourdes; Rey Saravia, Fernando Anibal; Brignole, Nélida Beatriz Se llevó a cabo la implementación de un predictor para el promedio diario de material particulado (PM) y el diseño y desarrollo de este software es descrito en este trabajo. El daño producido por el PM en la salud humana, está relacionado con el pequeño tamaño de las partículas. Las redes neuronales artificiales (RNs) han mostrado ser un método eficiente y universal en la aproximación de funciones para cualquier tipo de dato. Una RN fue escogida porque se ha demostrado que son eficaces cuando son aplicadas a predicciones de la calidad de aire. En comparación con otros trabajos similares, sólo una red fue realizada, pero varios prototipos fueron desarrollados y evaluados para evitar la arbitrariedad en las decisiones de diseño. Se experimentaron tres aspectos en particular del diseño de una RN: la normalización de los datos, la selección de la arquitectura y la selección de la función de activación. En base a nueve variables de entrada: dos estacionales, y siete meteorológicas; se determinó que la mejor candidata es una RN compuesta por: una capa de entrada lineal de nueve neuronas artificiales (NA), una capa oculta de catorce NA y una capa de salida de una NA; ambas con una función de activación tangente hiperbólica. Durante el desarrollo de un sistema de Data Warehousing (DW) para el monitoreo y control de polución en la ciudad de Bahía Blanca (Pcia. de Buenos Aires, Argentina), el conjunto de requerimientos incluía la necesidad de contar con herramientas que permitan la predicción de las concentraciones de varios contaminantes. En el futuro, esta herramienta terminada podrá ser embebida en dicho DW. Este trabajo es el comienzo del desarrollo de un entorno de predicción más complejo que abarcará diversos contaminantes en aire.

Crustal collapse in the Andean backarc since 2 Ma: Tromen volcanic plateau, Southern Central Andes (36°40′-37°30′S) Folguera Telichevsky, Andres; Bottesi, Germán; Zapata, Tomás; Ramos, Victor Alberto Analysis of seismic lines and gravity data shows the existence of Quaternary extensional depocenters beneath thick covers of < 1 Ma-old volcanic rocks in the Tromen volcanic plateau backarc region (36°40′-37°30′S). Dating and mapping of pre- and post-extensional volcanic units and structure in this area indicate that the main phase of crustal collapse developed during the 1.7-0.7 Ma time interval. However, Late Quaternary reactivations of the extensional structure show that this process is still going on, perhaps with decreasing intensity. Moreover, identification of "mechanical" rift zones and a potentially related main thermal anomaly leads to propose that an east-dipping detachment exists beneath the Late Cretaceous-Late Miocene fold and thrust belt, controlling the crustal collapse at these latitudes. The southernmost Central Andes (35°-37°30′S) have undergone a period of shallow subduction from ~ 13 to ~ 5 Ma, that led to expansion of the arc toward the foreland, generation of ductile-fragile crustal transitions, and subsequent foreland imbrications more than 550 km away from the trench. This framework shifted to a normal Andean subduction type after ~ 5 Ma, and the arc front re-established in the present western position. The consequences of this readjustment were: a) widespread volcanic eruptions of intra-plate melts in the eastern backarc (foreland plateau flows), and b) a major trough formed between the arc front and the foreland plateau basalts (Las Loicas trough). This extensional basin controlled the emplacement of crustal melts as well as primary mantle-derived products, well represented in the Tromen volcanic plateau.

Electrochemical evaluation of multilayer silica-metacrylate hybrid sol-gel coatings containing bioactive particles on surgical grade stainless steel Ballarre, Josefina; López, Damián; Rosero, Nataly C.; Durán, Alicia; Aparicio, Mario; Ceré, Silvia Metallic materials are the most used materials as orthopaedic or dental implants because of their excellent mechanical properties. However they are not able to create a natural bonding with the mineralized bone and occasionally suffer localized corrosion. This work describes the electrochemical behaviour of a system of coatings with the addition of bioactive particles of the system SiO2-CaO-P2 O5, that enhance the abilities of the implant to make an union with the existing bone and to resist the extreme environment that are exposed to. The coatings were obtain from two kind of sols that were made by sol-gel process: one, using tetraethoxysilane (TEOS) and methyl triethoxysilane (MTES) as precursors, and the other using hydroxyethyl methacylate (HEMA), tetraethoxysilane (TEOS) and 3-methacryloxypropyl-trimethoxysilane (γMPS) [TMH] as precursor. Coatings were made in two layers. The inner layer was prepared either using TEOS and MTES (that had already shown good anticorrosion properties), or TMH. The top layer was made with TMH with the addition of 10% in weight of small (diameter less than 20 μm) or big (more than 20 μm) bioactive particles. The samples were tested in vitro by polarization curves and electrochemical impedance spectroscopy (EIS) assays. The samples with the two kind of coatings seem to have a protective behaviour after 30 days of immersion due to the compact TEOS-MTES inner layer. The big particles placed in the outer layer showed a dissolution rate similar to the rate of deposition of the amorphous hydroxyapatite (aHAp) at the surface, blocking the entrance of the electrolyte, avoiding it to reach the substrate. The TMH coatings with small particles present a similar behaviour to the naked material, allowing the electrolyte to reach the metal. The dual coating with this kind of particles has similar characteristics, with a "sponge-like" behaviour, and the inner coating probably develops flaws due to the fast dissolution of the small particles placed in the upper layer. © 2008 Elsevier B.V. All rights reserved.

Open-field temporal pattern of ambulation in Japanese quail genetically selected for contrasting adrenocortical responsiveness to brief manual restraint Kembro, Jackelyn Melissa; Satterlee, Daniel G.; Schmidt, J. B.; Perillo, Maria Angelica; Marin, Raul Hector Japanese quail selected for a low-stress (LS), rather than a high-stress (HS), plasma corticosterone response to brief restraint have been shown to possess lower fearfulness and a nonspecific reduction in stress responsiveness. Detrended fluctuation analysis provides information on the organization and complexity of temporal patterns of behavior. The present study evaluated the temporal pattern of ambulation of LS and HS quail in an open field that represented a novel environment. Time series of 4,200 data points were collected for each bird by registering the distance ambulated every 0.5 s during a 35-min test period. Consistent with their known reduced fearfulness, the LS quail initiated ambulation significantly sooner (P < 0.02) and tended to ambulate more (P < 0.09) than did their HS counterparts. Detrended fluctuation analyses showed a monofractal series (i.e., a series with similar complexity at different temporal scales) in 72% of the birds. These birds initiated their ambulatory activity in less than 600 s. Among these birds, a lower (P < 0.03) autosimilarity coefficient (α) was found in the LS quail than in their HS counterparts (α = 0.76 ± 0.03 and 0.87 ± 0.03, respectively), suggesting a more complex (less regular) ambulatory pattern in the LS quail. However, when the patterns of ambulation were reexamined by considering only the active period of the time series (i.e., after the birds had initiated their ambulatory activity), monofractal patterns were observed in 97% of the birds, and no differences were found between the lines. Collectively, the results suggest that during the active period of open-field testing, during which fear responses are likely less strong and other motivations are the driving forces of ambulation, the LS and HS lines have similar ambulatory organization.

Simultaneous untangling and smoothing of moving grids Lopez, Ezequiel Jose; Nigro, Norberto Marcelo; Storti, Mario Alberto In this paper a technique for simultaneous untangling and smoothing of meshes is presented. Itis based on an extension of an earlier mesh smoothing strategy developed by the authors and used to solve the computational mesh dynamics stage in fluid-structure interaction problems. In moving grid problems, mesh untangling is necessary when element inversion happens due to a moving domain boundary. The original smoothing strategy is defined in terms of the minimization of a functional associated with the mesh distortion using an indicator of the element geometric quality. This functional becomes discontinuous when an element has null volume, making impossible to obtain a valid mesh from an invalid one. To circumvent this drawback, the original functional is transformed in order to guarantee its continuity for the whole space of nodal coordinates, achieving the untangling technique. The regularization depends on one parameter, allowing the recovery of the original functional when this parameter tends to zero. This feature is very important because at first it is necessary to regularize the functional in order to make the mesh valid, but then, it is advisable to use the original functional to make the smoothing optimal. This technique is applied to several test cases, including 2D and 3D meshes with simplicial elements. An additional example shows how this technique may be used for mesh generation.