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The protection of soft-skinned fruits against Drosophila suzukii has relied primarily on the efficacy of a few synthetic molecules. Despite their short-term efficacy, these molecules can cause environmental pollution, unintendedly affect non-target organisms, and fail to provide sustainable control. The shortfalls of using synthetic pesticides warrant the search for alternatives, such as essential oils extracted from plants, with greater eco-friendlier properties. Here, we chemically characterized and evaluated the toxicity of the essential oil extracted from leaves of Ocotea indecora (Schott) Mez (Lauraceae) against D. suzukii via two exposure pathways (ingestion and contact). We also assessed the selectivity of the essential oil to two predatory natural enemies, Eriopis connexa and Chrysoperla externa and two pollinator bees, Apis mellifera and Partamona helleri. In addition, we conducted in silico predictions to investigate potential interactions between the major compound of the essential oil and the insects' transient receptor potential (TRP) channels. Our chromatographic analysis revealed sesquirosefuran (87%) as the major compound. Higher toxicity to adults of D. suzukii was observed in contact exposure (LC50 = 0.43 µL mL-1) compared to ingestion (LC50 = 0.72 µL mL-1). However, the essential oil did not cause mortality to the non-target organisms tested here, even when applied at 2.20 µL mL-1. Molecular predictions demonstrated that sesquirosefuran binds more stably to the TRP channels of D. suzukii than to those expressed in beneficial arthropods. Collectively, our findings provide the initial framework for the potential use of O. indecora essential oil as a sustainable alternative for managing D. suzukii infestations.

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The mining industry has resorted to using seawater while trying to find a solution to the water shortage, which is severe in some regions. Today, the industry looks to tailings dams to recover more water and, thus, increase recirculation. The migration of interstitial water due to the consolidation of particle networks can give rise to large water mirrors in different dam areas. These pools can contain enough water to be recovered and recirculated if the external stress caused by the weight of the pulp exceeds the compressive yield stress. The density and rheological properties of the discarded pulps determine the feasibility of water expulsion during tailings consolidation. As these conditions are largely established in the thickening stage, it is necessary to revisit operations, looking at the dam as a water source. Thus, a thorough understanding of the compressive properties that determine the level of consolidation of typical pulps and their relationships to aggregate properties, such as size and fractal dimension, is crucial. Here, the effect of two types of water, industrial water and synthetic seawater, on kaolin flocculation, sedimentation rate, yield stress, and compressive yield stress were studied. In addition, the relationship of these properties with the flocculant dose and the resulting aggregate size and fractal dimension was examined. One promising finding to practitioners was that salt and small doses of high molecular weight flocculant improved the consolidation of kaolin slurries under compression. These conditions generated low compressive yield stress compared to fresh water and water with low salt content, favoring the consolidation of the pulps and the release of water.

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Seaweeds are a rich source of nutritional and functional compounds, but they also accumulate heavy metals. Here, the chemical composition (crude protein, total lipids, Nitrogen Free Extract and fiber) and the presence of minerals (Na, K, Ca, Mg, P, Fe, Mn, Cu, Zn, Mo, Se) and unwanted elements (As, Cd, Hg, Pb, Ni, Cr, Al) were determined in eleven seaweeds from Chile. Depending on the species, a good contribution to the Recommended Dietary Allowance for K, Ca, Mg, Fe, Mn and Se was observed, and low Na/K ratios (<1.0) as well. The health risk assessment indicated low hazard due to intake of seaweed meal. The mean values of As, Hg, and Pb were below the maximum limits set for food supplements and feed ingredients. The seaweeds studied have a suitable chemical composition for their uses as food and feed ingredients, although Cd levels should be monitoring especially in brown seaweeds.

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Methyl isobutyl carbinol (MIBC) is a high-performance surfactant with unusual interfacial properties much appreciated in industrial applications, particularly in mineral flotation. In this study, the structure of air-liquid interfaces of aqueous solutions of MIBC-NaCl is determined by using molecular dynamics simulations employing polarizable and nonpolarizable force fields. Density profiles at the interfaces and surface tension for a wide range of MIBC concentrations reveal the key role of polarizability in determining the surface solvation of Cl- ions and the expulsion of non-polarizable Na+ ions from the interface to the liquid bulk, in agreement with spectroscopic experiments. The orientation of MIBC molecules at the water liquid-vapor interface changes as the concentration of MIBC increases, from parallel to the interface to perpendicular, leading to a well-packed monolayer. Surface tension curves of fresh water and aqueous NaCl solutions in the presence of MIBC intersect at a reproducible surfactant concentration for a wide range of salt concentrations. The simulation results for a 1 M NaCl aqueous solution with polarizable water and ions closely capture the MIBC concentration at the intercept. The increase in surface tension of the aqueous MIBC/NaCl mixture below the concentration of MIBC at the intersection seems to originate in a disturbance of the interfacial hydrogen bonding structure of the surface liquid water caused by Na+ ions acting at a distance and not by its presence on the interface.

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Dispersants under certain conditions favor the flotation of molybdenite in seawater; however, it is not clear if the entrainment of residues to the thickening stage can compromise the quality of the clarified water. In this work, the impact of small concentrations of sodium hexametaphosphate (SHMP) on the flocculation and sedimentation of synthetic tailings containing kaolinite, muscovite, and quartz in seawater is evaluated. The flocculant polymer is a high-molecular-weight polyacrylamide, and the pH is alkaline. The results are auspicious for mineral processing. On the one hand, the impact of SHMP is not entirely negative and can be lessened by limiting entrainment, which is good for copper and molybdenum ore processing. On the other hand, if the small increase in turbidity generated by the SHMP is tolerated, it is possible to expect improved settling speeds. Without SHMP, large but light agglomerates are formed. With SHMP, smaller but denser aggregates are formed, settling faster, and minute aggregates increase turbidity. The underlying mechanism derives from the competition between SHMP and polymer chains for the cations in solution; the result is a greater repulsion between the chains, which leads to greater repulsion and thus dispersion of smaller flocculant coils. The study shows that SHMP in concentrations of 1 to 3 kg/t is perfectly acceptable. The results represent an advance in the understanding of SHMP interactions with polymers and minerals in water clarification, which should be of interest to the industry whose sustainability in some regions depends on closing the water cycle.

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The resistance of kaolin aggregates to shearing in water clarification and recovery operations is a critical input in designing thickener feed wells. A recently formulated but already available criterion is used to determine the shear strength of flocculated kaolin aggregates. The flocculant is a high molecular weight anionic polyelectrolyte. The resistance of the aggregates is evaluated as a function of flocculation time, flocculant dosage, and water quality. The determination is based on a standardized experimental method. First, the time evolution of the average size of kaolin flocs is measured when aggregates are exposed to incremental shear rates from a predetermined base value. Then, the results are fitted to a pseudo-first-order model that allows deriving a characteristic value of the shear rate of rupture associated with the upper limit of the strength of the aggregates. In seawater, at a given dose of flocculant, the strength of the aggregates increases with time up to a maximum; however, at longer times, the resistance decreases until it settles at a stable value corresponding to stable aggregates in size and structure. A higher flocculant dosage leads to stronger aggregates due to more bridges between particles and polymers, leading to a more intricate and resistant particle network. In industrial water with very low salt content, the resistance of the kaolin aggregates is higher than in seawater for the same dose of flocculant. The salt weakens the resistance of the aggregates and works against the efficiency of the flocculant. The study should be of practical interest to concentration plants that use seawater in their operations.

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Interactive movements of bees facilitate the division and organization of collective tasks, notably when they need to face internal or external environmental challenges. Here, we present a Bayesian and computational approach to track the movement of several honey bee, Apis mellifera, workers at colony level. We applied algorithms that combined tracking and Kernel Density Estimation (KDE), allowing measurements of entropy and Probability Distribution Function (PDF) of the motion of tracked organisms. We placed approximately 200 recently emerged and labeled bees inside an experimental colony, which consists of a mated queen, approximately 1000 bees, and a naturally occurring beehive background. Before release, labeled bees were fed for one hour with uncontaminated diets or diets containing a commercial mixture of synthetic fungicides (thiophanate-methyl and chlorothalonil). The colonies were filmed (12 min) at the 1st hour, 5th and 10th days after the bees' release. Our results revealed that the algorithm tracked the labeled bees with great accuracy. Pesticide-contaminated colonies showed anticipated collective activities in peripheral hive areas, far from the brood area, and exhibited reduced swarm entropy and energy values when compared to uncontaminated colonies. Collectively, our approach opens novel possibilities to quantify and predict potential alterations mediated by pollutants (e.g., pesticides) at the bee colony-level.

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Seawater treated with lime and sodium carbonate in different proportions to reduce magnesium and calcium contents is used in flocculation and sedimentation tests of artificial quartz and kaolin tailings. Solid complexes were separated from water by vacuum filtration, and factors such as lime/sodium carbonate ratio, kaolin content, flocculation time, and flocculant dose are evaluated. The growth of the aggregates was captured in situ by a focused beam reflectance measurement (FBRM) probe. Solid magnesium and calcium complexes are formed in raw seawater at pH 11, impairing the performance of flocculant polymers based on polyacrylamides. The results show that the settling rate improved when the treatment's lime/sodium carbonate ratio increased. That is, when a greater removal of magnesium is prioritized over calcium. The amount of magnesium required to be removed depends on the mineralogy of the system: more clay will require more significant removal of magnesium. These results respond to the structural changes of the flocs, achieving that the more magnesium is removed, the greater the size and density of the aggregates. In contrast, calcium removal does not significantly influence flocculant performance. The study suggests the necessary conditions for each type of tailing to maximize water recovery, contributing to the effective closure of the water cycle in processes that use seawater with magnesium control.

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El presente libro está dividido en cinco partes: I. Planteamiento del problema., II. Bases científicas del adulterio: Una revisión de los aspectos biológicos, antropológicos, neurológicos y psicológicos., III. Adulterio y sociedad. Un examen de los aspectos socioculturales de la monogamia en relación a la ley, religión y arte., IV. Aspectos clínicos del adulterio: el dolor y las consecuencias que ocasiona la traición., V. Tratamientos. Se ocupa de la terapia de pareja en caso de adulterio y de los celos patológicos. El capítulo uno es de índole semántica. Diferencia adulterio de infidelidad y engaño; Asimismo, de las situaciones límite, delitos y psicopatología. Redefine el concepto adulterio en las parejas de convivientes conformadas por personas separadas no divorciadas. Todo ello, para tener un lenguaje científico común. El capítulo dos plantea el problema del adulterio como un hecho histórico tan frecuente que lleva a pensar si acaso no obedece a una pulsión promiscua natural en contradicción con la exigencia de fidelidad del matrimonio monogámico. Algunos factores biológicos de la sexualidad humana -genéticos, endocrinos, neurológicos y etológicos-, que podrían sustentar una base instintiva promiscua, se describen en el capítulo tres. El capítulo cuatro escudriña si los primeros humanos fueron promiscuos, para explicar una eventual herencia polígama del hombre moderno. Se explora el asiento anatómico y la química cerebral del enamoramiento, en el capítulo cinco. El capítulo seis compara los amores romántico, conyugal y excelso. El capítulo siete muestra la base económico-social del matrimonio monógamo, sus crisis y el eventual divorcio. Se examina el adulterio ante la ley como causal de divorcio, en el capítulo ocho. Se propone a los psiquiatras recomendaciones para la correcta certificación médica en el Poder Judicial. El capítulo nueve contiene las actitudes de la religión ante el adulterio: condena, perdón, derecho al divorcio; asimismo, las incongruencias de algunos pacientes religiosos y la lapidación musulmana como castigo. Se presentan dos casos de adulterio de figuras políticas que llevaron a sus respectivos Estados a un remezón internacional; y dos casos nacionales de escándalo, en el capítulo diez. En el capítulo once, se exhibe la infidelidad en la literatura universal como reflejo del drama de los seres humanos. El capítulo doce estudia el feminicidio, su distribución en América Latina y las bases neurológicas de la furia asesina. Del miedo a comprometerse en matrimonio, por parte de los varones, y de las mujeres a quedarse solteras, trata el capítulo trece. En el capítulo catorce, se describen las alternativas ensayadas ante las limitaciones de la monogamia: matrimonio grupal, matrimonio abierto y los grupos beatnik. Los motivos del adulterio, principalmente el déficit de amor y relaciones sexuales, se analizan en el capítulo quince. Finalmente, se verifica que la infidelidad se da por una conjunción de factores psíquicos, culturales y económicos. Las señales de infidelidad, las maniobras que realiza el adúltero para no ser descubierto y los indicios inevitables que va dejando en su aventura, se tratan en el capítulo dieciséis. Un caso particular son los actos fallidos, venidos del inconsciente, que lo delatan. Además, se examina el caso de la víctima que ignora los signos de la infidelidad. En el capítulo diecisiete, se describe el dolor del cónyuge ofendido, las reacciones psíquicas y conductuales inmediatas como la violencia y la depresión. Además, se examinan las tribulaciones del ofensor. En el capítulo dieciocho, se describen las consecuencias del adulterio en cada miembro de la pareja, la familia y la sociedad. Se examina el sufrimiento que sigue, el resentimiento a largo plazo y la eventual disfunción matrimonial. Los aspectos de la psicoterapia de pareja en el adulterio consumado, se muestran en el capítulo diecinueve. Se presentan cuatro enfoques psicológicos de interés, sus bases teóricas, la personalidad del terapeuta y las técnicas de intervención. El capítulo veinte trata de la intervención del terapeuta en la pareja ya separada y su eventual reconciliación o divorcio. En el capítulo veintiuno, se exploran los celos y sus tipos. Se presta atención a la celotipia, una forma de psicosis paranoica en la que el enfermo imagina convencido de modo irreductible que el cónyuge es infiel; entonces, sufre y hace sufrir, como si hubiese sido traicionado realmente. Se propone el tratamiento de los celos a base de medicamentos, medidas higiénicas y psicoterapia, en el capítulo veintidós. El capítulo veintitrés ofrece algunas recomendaciones prácticas de cómo reaccionar ante la noticia de adulterio. Se dan sugerencias, tanto para el ofendido como para el ofensor. Finaliza el texto con las principales conclusiones acerca del adulterio

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BACKGROUND: Using plant-based extracts and their constituents has been suggested as an alternative tool to replace or integrate with the synthetic compounds used to manage insect pests. Here, we evaluated the potential of extracts obtained from Ficus carica Linn (Moraceae) branches and leaves against the Neotropical brown stink bug, Euschistus heros, one of the most prevalent insect pests in soybean fields. We further isolated and evaluated the toxicity of the extracts' major components against E. heros. Additionally, by using computational docking analysis and toxicological approaches, we assessed the physiological basis for the selectivity of these extracts against beneficial insects such as pollinator bees (i.e. Apis mellifera and the Neotropical stingless bee Partamona helleri), ladybeetles (Eriopis connexa and Coleomegilla maculata), and lacewings (Chrysoperla externa). RESULTS: Our results demonstrate that branch (LC50  = 5.9 [4.7-7.1] mg mL-1 ) and leaf (LC50  = 14.1 [12.5-15.4] mg mL-1 ) extracts exhibited similar toxicity against E. heros. Our phytochemical analysis revealed psoralen and bergapten furanocoumarins as the major components of the extract. Based on our computational predictions, these molecules' differential abilities to physically interact with the acetylcholinesterases of E. heros and beneficial insects play relevant roles in their selectivity actions. The estimated LC90 values of branch (30.0 mg mL-1 ) and leaf (30.0 mg mL-1 ) extracts killed less than 12% of the beneficial insects. CONCLUSION: Overall, our findings revealed that furanocoumarin-rich extracts obtained from F. carica extracts have the potential to be used as alternative tools in the integrated management of stink bug pests. © 2021 Society of Chemical Industry.

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Stingless bees such as Partamona helleri Friese play important roles in pollination of native plants and agricultural crops in the Neotropics. Global concerns about declining bee populations due to agrochemical pollutants have, however, been biased towards the honey bee, Apis mellifera Linnaeus. Here, we analysed the unintended effects of commercial formulations of a neonicotinoid insecticide, imidacloprid, and a fungicide mixture of thiophanate-methyl and chlorothalonil on color preference, respiration rates and group locomotory activities of both P. helleri and A. mellifera. Our results revealed that P. helleri foragers that were not exposed to pesticides changed their color preference during the course of a year. By contrast, we found that pesticide exposure altered the color preference of stingless bees in a concentration-dependent manner. In addition, imidacloprid decreased the overall locomotion of both bee species, whereas the fungicide mixture increased locomotion of only stingless bees. The fungicide mixture also reduced respiration rates of forager bees of both species. Forager bees of both species altered their color preference, but not their locomotory and respiration rates, when exposed to commercial formulations of each fungicidal mixture component (i.e., chlorothalonil and thiophanate-methyl). Our findings emphasize the importance of P. helleri as a model for Neotropical wild pollinator species in pesticide risk assessments, and also the critical importance of including groups of agrochemicals that are often considered to have minimal impact on pollinators, such as fungicides.

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The plant-based biopesticides have been proposed as insect pest control tools that seem to be safer for the environment and human health when compared to synthetic conventional molecules. However, such assumptions are generally made without considering the absence of detrimental effects on sublethally-exposed non-target organisms or showing the physiological basis of the selective action of such botanical products. Thus, by using in silico-based and in vivo toxicological approaches, the present investigation aimed to disentangle the ecotoxicological selectivity of clove, Syzygium aromaticum, essential oil against the aphid Rhopalosiphum maidis and the non-target ladybeetle, Coleomegilla maculata. We also investigated whether the sublethal exposure to clove essential oil would affect the locomotory and predatory abilities of C. maculata. We found that the clove essential oil concentration estimated to kill 95% (LC95: 0.17 µL/cm2) of the aphids was lethal to <18% of C. maculata. Indeed, our in silico results reinforced such differential susceptibility, as it predicted that eugenol and ß-caryophyllene (i.e., the clove essential oil major components) bound to three potential molecular targets (i.e., transient receptor potential (TRP) channels, octopamine, and gamma-aminobutyric acid (GABA) receptors) of the aphids but only to the octopamine receptors of the ladybeetles. Additionally, the ladybeetles that were exposure to the clove essential oil exhibited unaffected abilities to locomote and to prey upon R. maidis aphids when compared to unexposed ladybeetles. Thus, by displaying lower toxicity against the ladybeetles, the clove essential oil represents a safer alternative tool to be integrated into programs aiming to manage aphid infestations.

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Plant essential oils are regarded as interesting alternative tools to be integrated into the management of pest insects. However, as they generally consist of mixtures of numerous molecules, the physiological basis for their action is unresolved. Here, we evaluated the effects of essential oil of the Neotropical plant Siparuna guianensis Aubl., commonly known as Negramina, against an important pest insect: the green peach aphid Myzus persicae (Sulzer), and also in two non-target natural enemies: the ladybeetle predators Coleomegilla maculata (DeGeer) and Eriopis connexa (Germar). In addition, we conducted a computational docking analysis for predicting the physical interactions between the two Negramina essential oil major constituents: ß-myrcene and 2-undocanone, and the transient receptor potential (TRP) channels as potential binding receptors in the aphid and ladybeetles. As the most important results, Negramina essential oil caused mortality in M. persicae aphids with an LC95 = 1.08 mg/cm2, and also significantly repelled the aphids at concentrations as low as 0.14 mg/cm2. Our computational docking analysis reinforced such selectivity actions as the Negramina essential oil major compounds (i.e., ß-myrcene and 2-undocanone) bound to the TRP channels of M. persicae but not to ladybeetle-related TRP channels. Interestingly, the exposure to the Negramina essential oil did not affect the predatory abilities of C. maculata but increased the abilities of E. connexa to prey upon M. persicae. Collectively, our findings provided a physiological basis for the insecticidal and selectivity potential of Negramina essential oil, reinforcing its potential as a tool to be used in integrated pest control programs.

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RESUMO A exploração indiscriminada de água subterrânea pode causar o colapso dos aquíferos costeiros. Nesse escopo, este trabalho avaliou o comportamento da cunha salina em parte do sistema Barreiras/Marituba, que fica na costa da região metropolitana de Maceió (AL), fazendo uso de modelagem e índices hidrogeoquímicos. O modelo foi calibrado tanto para o fluxo subterrâneo como para a concentração de sólidos totais dissolvidos, nos quais atingiu coeficiente de correlação de 0,764 e 0,682, respectivamente. Foram analisados dois cenários distintos, que permitiram verificar o efeito da explotação de água subterrânea na cunha salina para uma projeção de dez anos. O primeiro considerou a explotação existente até 2015, sem acréscimos de bombeamentos. Como resultado, verificou-se o avanço da cunha salina em duas áreas do domínio e outra área sofreu recuo, além da formação de cones com ascensão vertical da água do mar. No segundo cenário, foram adicionadas, além das licenças de obras hídricas já existentes, como poços, a hipótese de instalação de 36 novos poços de bombeamento, considerando o crescimento da cidade. Porém, nesse caso, não foi possível visualizar variações significativas na zona de mescla em relação ao primeiro cenário. A análise dos índices hidrogeoquímicos apontou para maiores concentrações de cloretos na região próxima à linha do Oceano Atlântico, com pouca influência do nitrato e, no geral, indicou a existência de intrusão de água do mar.

ABSTRACT The groundwater overexploitation can cause the collapse of coastal aquifers. In this scope, this study evaluated the behavior of the salt wedge in part of the Barreiras/Marituba system aquifer present on the coast of the Metropolitan Region of Maceió, Alagoas, using hydrogeochemical modeling and indexes. The model was calibrated for both the underground flow and the total dissolved solids concentration, obtaining a correlation coefficient of 0.764 and 0.682, respectively. Two different scenarios were analyzed, which allowed verifying the effect of the exploitation of groundwater in the salt wedge for a projection of 10 years. The first considered the existing operation until 2015, without any additional pumping. Results shows that saline wedge advanced in two areas of the domain and another site was retreated, in addition to the formation of cones with vertical rise of the sea water. The second scenario, besides the already existing waterworks licenses, was also added by the installation of 36 hypothetical pumping wells, based in the city growth. However, in this case, it was not possible to visualize significant variations in the melting zone in relation to the first scenario. The analysis of hydrogeochemical indices shows to higher concentrations of chlorides in the region near the Atlantic Ocean line, with little influence of nitrate and, in general, indicated the existence of sea water intrusion.

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Introducción. La evaluación de la calidad de vida relacionada con la salud (CVRS) permite detectar cambios en el tiempo en la salud de pacientes y posibilita realizar un análisis de coste-efectividad de tratamientos. En niños con características especiales de salud que no pueden autoevaluarse, existe la posibilidad de evaluar su CVRS a través de padres o cuidadores. Hasta la fecha, no se ha analizado la discrepancia en la evaluación de la CVRS a través del cuestionario EQ-5D-Y entre niños con parálisis cerebral (PC) y sus padres. El objetivo del presente estudio fue analizar el grado de concordancia en la evaluación de la CVRS a través del cuestionario EQ-5D-Y y su versión Proxy entre niños con PC y sus padres o cuidadores. Población y métodos. Participaron, en el estudio, niños y adolescentes con PC, así como sus padres y madres, procedentes de un centro de educación especial de la región de Extremadura (España). Se utilizó el cuestionario EQ-5D-Y para los niños y el EQ-5D-Y Proxy para los padres. Las entrevistas fueron llevabas a cabo durante el primer trimestre de 2015. Se analizó la concordancia en las respuestas mediante el nivel de acuerdo con kappa de Cohen para las 5 dimensiones que componen el EQ-5D-Y y el coeficiente de correlación intraclase para la escala visual analógica. Resultados. Participaron 62 niños con PC con afectación leve y/o moderada de su capacidad funcional, sus padres y madres. Hubo una pobre concordancia en la evaluación de la CVRS entre niños y padres en todas las dimensiones del cuestionario (< 0, 20) y justo o pobre (< 0, 60) en la escala visual analógica. Conclusiones. Existe un alto desacuerdo en la evaluación de la CVRS entre padres e hijos en población con PC a través del cuestionario EQ-5D-Y.

Introduction. The assessment of health-related quality of life (HRQoL) serves to detect changes over time in patients' health status and allows to do a cost-effectiveness analysis of treatments. When children with special health features cannot perform a self-assessment, it is possible to assess their HRQoL through their parents or caregivers. To date, the discrepancy in the assessment of HRQoL using the EQ-5D-Y questionnaire among children with cerebral palsy (CP) and their parents has not been analyzed. The objective of this study was to analyze the level of agreement in the HRQoL assessment using the EQ-5D-Y questionnaire and its proxy version among children with CP and their parents or caregivers. Population and methods. Children and adolescents with CP, and their parents, from a special education school in the region of Extremadura (Spain) participated in the study. The EQ-5D-Y questionnaire was used for children and the EQ-5D-Y proxy version, for parents. Interviews were conducted in the first quarter of 2015. The level of agreement in the responses was analyzed using the Cohen's kappa coefficient for the five domains of the EQ-5D-Y and the intraclass correlation coefficient for the visual analogue scale. Results. Sixty-two children with CP and mild and/or moderate functional capacity impairment, and their parents, participated in the study. The level of agreement was poor in the HRQoL assessment between children and parents in all the questionnaire domains (<0.20) and fair or poor (<0.60) in the visual analogue scale. Conclusions. A high level of parent-child disagreement was observed in the HRQoL assessment in the population with CP using the EQ-5D-Y questionnaire.

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INTRODUCTION: The assessment of health-related quality of life (HRQoL) serves to detect changes over time in patients' health status and allows to do a cost-effectiveness analysis of treatments. When children with special health features cannot perform a self-assessment, it is possible to assess their HRQoL through their parents or caregivers. To date, the discrepancy in the assessment of HRQoL using the EQ-5D-Y questionnaire among children with cerebral palsy (CP) and their parents has not been analyzed. The objective of this study was to analyze the level of agreement in the HRQoL assessment using the EQ-5D-Y questionnaire and its proxy version among children with CP and their parents or caregivers. POPULATION AND METHODS: Children and adolescents with CP, and their parents, from a special education school in the region of Extremadura (Spain) participated in the study. The EQ-5D-Y questionnaire was used for children and the EQ-5D-Y proxy version, for parents. Interviews were conducted in the first quarter of 2015. The level of agreement in the responses was analyzed using the Cohen's kappa coefficient for the five domains of the EQ-5D-Y and the intraclass correlation coefficient for the visual analogue scale. RESULTS: Sixty-two children with CP and mild and/or moderate functional capacity impairment, and their parents, participated in the study. The level of agreement was poor in the HRQoL assessment between children and parents in all the questionnaire domains ( <0.20) and fair or poor ( <0.60) in the visual analogue scale. CONCLUSIONS: A high level of parent-child disagreement was observed in the HRQoL assessment in the population with CP using the EQ-5D-Y questionnaire.

INTRODUCCIÓN: La evaluación de la calidad de vida relacionada con la salud (CVRS) permite detectar cambios en el tiempo en la salud de pacientes y posibilita realizar un análisis de coste-efectividad de tratamientos. En niños con características especiales de salud que no pueden autoevaluarse, existe la posibilidad de evaluar su CVRS a través de padres o cuidadores. Hasta la fecha, no se ha analizado la discrepancia en la evaluación de la CVRS a través del cuestionario EQ-5D-Y entre niños con parálisis cerebral (PC) y sus padres. El objetivo del presente estudio fue analizar el grado de concordancia en la evaluación de la CVRS a través del cuestionario EQ-5D-Y y su versión Proxy entre niños con PC y sus padres o cuidadores. POBLACIÓN Y MÉTODOS: Participaron, en el estudio, niños y adolescentes con PC, así como sus padres y madres, procedentes de un centro de educación especial de la región de Extremadura (España). Se utilizó el cuestionario EQ-5D-Y para los niños y el EQ-5D-Y Proxy para los padres. Las entrevistas fueron llevabas a cabo durante el primer trimestre de 2015. Se analizó la concordancia en las respuestas mediante el nivel de acuerdo con kappa de Cohen para las 5 dimensiones que componen el EQ-5D-Y y el coeficiente de correlación intraclase para la escala visual analógica. RESULTS: Participaron 62 niños con PC con afectación leve y/o moderada de su capacidad funcional, sus padres y madres. Hubo una pobre concordancia en la evaluación de la CVRS entre niños y padres en todas las dimensiones del cuestionario (< 0,20) y justo o pobre (< 0,60) en la escala visual analógica. CONCLUSIONS: Existe un alto desacuerdo en la evaluación de la CVRS entre padres e hijos en población con PC a través del cuestionario EQ-5D-Y.

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Nanotubes are formed by self-assembly of α-lactalbumin milk protein following a different route than established for the hydrolysis which involves V8 enzyme, phosphate buffer and appropriate amounts of calcium at neutral pH. The resulting nanotubes are used as templates for the growth of conductive silver nanotubes. TEM, SEM-EDS, AFM and FTIR are used for characterization.

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The net interaction between a probe tip coated with bovine serum albumin (BSA) protein and a flat substrate coated with poly(ethylene oxide) (PEO) polymer was measured directly on approach in water and electrolyte solutions using AFM. The approach force curve between the two surfaces was monotonically repulsive in water and in electrolyte solutions. At pH ~5, slightly above the isoelectric point (pI) of BSA, and at large distances, the force was dominated by electrostatic repulsion between the oxygen atoms of the incoming protein with those belonging to the ether groups of PEO. Such repulsive force and range decreased in NaCl. Under physiological conditions, pH 6, BSA is definitely charged and the electrostatic repulsion with ether groups in PEO appears at larger separation distances. Interestingly, at pH 4, below the pI of BSA, the repulsion decreased because of an attractive, although weak, electrostatic force that appeared between the ether groups in PEO and the positively charged amino groups of BSA. However, for all solution conditions, once compression of PEO begun, the net repulsion was always dominated by short-range polymeric steric repulsion and repulsive enthalpy penalties for breaking PEO-water bonds. Results suggest that PEO in mushroom conformation may also be effective in reducing biofouling.

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Molecular dynamics simulation of a nanoscale capillary water bridge between two planar substrates is used to determine the resulting force between the substrates without arbitrariness regarding geometry and location of the free surface of the bridge. The substrates are moderately hydrophilic. The force changes continuously as the separation between the substrates changes except for small gaps where it becomes discontinuous because the bridge is unable to adopt stable configurations at any distance apart. Further exploration of the bridge and the force as the substrates approach each other reveals an underlying oscillatory force with an increasing repulsive component at separation distances equivalent to few water molecules. According to the average number of hydrogen bonds per water molecule (HBN), at very small gap sizes, water molecules which are very close to the surfaces are unable to maximize HBN thus contributing to the repulsive force. Our simulation results of force versus gap size agree with calculations based on other methods, some very different, and also reproduce the typical magnitude of the experimental force. Finally, a macroscopic force balance correctly describes the force-distance curve except for bridges constituted of water layers only.

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A population balance model based on a detailed literature review is used to describe coagulation and flocculation kinetics as well as the time evolution of aggregate size distribution in a turbulent shear flow simultaneously with the breakage and restructuring of aggregates. The fractal nature and permeability of the aggregates and their evolution with time are also part of the model. Restructuring is absent in coagulation with soluble salts, but is present in flocculation caused by large polyelectrolyte molecules; in the latter, aggregates never reach a steady-state size, but a size that decreases gradually through particle and polymer rearrangement. The model is tested against available experimental data for monodisperse polystyrene particles coagulated with hydrated aluminium sulphate at different shear rates, and precipitated calcium carbonate flocculated with a cationic polyelectrolyte of very high molecular weight at different flocculant dosages. The numerical solution of the model requires adjusting three parameters, i.e, maximum collision efficiency (αmax), critical force needed for the breakage of the aggregates (B) and rate of aggregate restructuring (γ), which are obtained from minimising the difference between experimental data and model predictions. The model studied for the two very different systems shows excellent agreement with experimental flocculation kinetics and a reasonably good fit for aggregate size distributions. The model is most sensitive to the fragmentation rate through parameter B, somewhat less to the collision efficiency through parameter αmax and little to γ. When the aggregates undergo restructuring, properties such as permeability, breakage rate and collision rate change considerably over time. When the aggregates are permeable, the collision frequency is significantly smaller than when they are impervious.