Properties and thermal behavior of natural deep eutectic solvents

Natural deep eutectic solvents (NADES) have shown to be promising sustainable media for a wide range of applications. Nonetheless, very limited data is available on the properties of these solvents. A more comprehensive body of data on NADES is required for a deeper understanding of these solvents at molecular level, which will undoubtedly foster the development of new applications. NADES based on choline chloride, organic acids, amino acids and sugars were prepared, and their density, thermal behavior, conductivity and polarity were assessed, for different NADES compositions. The NADES studied can be stable up to 170 Â°C, depending on their composition. The thermal characterization revealed that all the NADES are glass formers and some, after water removal, exhibit crystallinity. The morphological characterization of the crystallizable materials was performed using polarized optical microscopy which also provided evidence of homogeneity/phase separation. The conductivity of the NADES was also assessed from 0 to 40 Â°C. The more polar, organic acid-based NADES presented the highest conductivities. The conductivity dependence on temperature was well described by the Vogelâ Fulcherâ Tammann equation for some of the NADES studied.

Embedding, evolution, and validation of model-driven spreadsheets

This paper proposes and validates a model-driven software engineering technique for spreadsheets. The technique that we envision builds on the embedding of spreadsheet models under a widely used spreadsheet system. This means that we enable the creation and evolution of spreadsheet models under a spreadsheet system. More precisely, we embed ClassSheets, a visual language with a syntax similar to the one offered by common spreadsheets, that was created with the aim of specifying spreadsheets. Our embedding allows models and their conforming instances to be developed under the same environment. In practice, this convenient environment enhances evolution steps at the model level while the corresponding instance is automatically co-evolved.Finally,wehave designed and conducted an empirical study with human users in order to assess our technique in production environments. The results of this study are promising and suggest that productivity gains are realizable under our model-driven spreadsheet development setting.

Development and characterization of lipid-based nanosystems for controlled release of bioactive compounds

Tese de Doutoramento em Engenharia Química e Biológica.

The effect of high-fat diet on rat’s mood, feeding behavior and response to stress

An association between obesity and depression has been indicated in studies addressing common physical (metabolic) and psychological (anxiety, low self-esteem) outcomes. Of consideration in both obesity and depression are chronic mild stressors to which individuals are exposed to on a daily basis. However, the response to stress is remarkably variable depending on numerous factors, such as the physical health and the mental state at the time of exposure. Here a chronic mild stress (CMS) protocol was used to assess the effect of high-fat diet (HFD)-induced obesity on response to stress in a rat model. In addition to the development of metabolic complications, such as glucose intolerance, diet-induced obesity caused behavioral alterations. Specifically, animals fed on HFD displayed depressive- and anxious-like behaviors that were only present in the normal diet (ND) group upon exposure to CMS. Of notice, these mood impairments were not further aggravated when the HFD animals were exposed to CMS, which suggest a ceiling effect. Moreover, although there was a sudden drop of food consumption in the first 3 weeks of the CMS protocol in both ND and HFD groups, only the CMS-HFD displayed an overall noticeable decrease in total food intake during the 6 weeks of the CMS protocol. Altogether, the study suggests that HFD impacts on the response to CMS, which should be considered when addressing the consequences of obesity in behavior.

O simbólico como estratégia para a alteração comportamental: o caso Águas do Porto

Dissertação de mestrado em Ciências da Comunicação (área de especialização em Publicidade e Relações Públicas)

Development of Monoolein-based lipofection vectors for therapeutic siRNA delivery

Tese de Doutoramento em Biologia Molecular e Ambiental - Especialidade em Biologia Celular e Saúde

Development of multifunctional coatings deposited on polymers based sensors for biomedical applications

Tese de Doutoramento (Programa Doutoral em Engenharia de Materiais)

Development of a poly(L-Lactic acid) based drug release system

Dissertação de mestrado em Biofísica e Bionanossistemas

Mother’s depression at childbirth does not contribute to the effects of antenatal depression on neonate’s behavioral development

Background: Maternal depression is a worldwide phenomenon that has been linked to adverse developmental outcomes in neonates. Aims: To study the effect of antenatal depression (during the third trimester of pregnancy) on neonate behavior, preference, and habituation to both the mother and a stranger’s face/voice. To analyze mother’s depression at childbirth as a potential mediator or moderator of the relationship between antenatal depression and neonate behavioral development. Method: A sample of 110 pregnant women was divided in 2 groups according to their scores on the Edinburgh Postnatal Depression Scale during pregnancy (EPDS; ≥10, depressed; <10, non-depressed). In the first 5 days after birth, neonatal performance on the Neonatal Behavioral Assessment Scale (NBAS) and in the ‘Preference and habituation to the mother’s face/voice versus stranger’ paradigm was assessed; each mother filled out an EPDS. Results: Neonates of depressed pregnant women, achieved lower scores on the NBASs (regulation of state, range of state, and habituation); did not show a visual/auditory preference for the mother’s face/voice; required more trials to become habituated to the mother’s face/voice; and showed a higher visual/auditory preference for the stranger’s face/voice after habituation compared to neonates of non-depressed pregnant women. Depression at childbirth does not contribute to the effect of antenatal depression on neonatal behavioral development. Conclusion: Depression even before childbirth compromises the neonatal behavioral development. Depression is a relevant issue and should be addressed as a routine part of prenatal health care.

Prenatal dopamine and neonatal behavior and biochemistry

Depressed pregnant women (N=126) were divided into high and low prenatal maternal dopamine (HVA) groups based on a tertile split on their dopamine levels at 20 weeks gestation. The high versus the low dopamine group had lower Center for Epidemiological Studies-Depression Scale (CES-D) scores, higher norepinephrine levels at the 20-week gestational age visit and higher dopamine and serotonin levels at both the 20- and the 32-week gestational age visits. The neonates of the mothers with high versus low prenatal dopamine levels also had higher dopamine and serotonin levels as well as lower cortisol levels. Finally, the neonates in the high dopamine group had better autonomic stability and excitability scores on the Brazelton Neonatal Behavior Assessment Scale. Thus, prenatal maternal dopamine levels appear to be negatively related to prenatal depression scores and positively related to neonatal dopamine and behavioral regulation, although these effects are confounded by elevated serotonin levels.

Postpartum Depression: Is it a condition affecting the mother-infant interaction and the development of the child across the first year of life?

Noting that maternal depression is common during a baby's first year, this study examined the interaction of depressed and non-depressed mother-child dyads. A sample of 26 first-time mothers with postpartum depression at the third month after birth and their 3-month-old infants was compared to a sample of 25 first-time mothers with no postpartum depression at the third month after birth and their 3-month-old infants. The observations were repeated at 6 months and again at 12 months postpartum. The samples were compared for differences in mother interaction behavior, mother's infant care, mother's concern with the baby, infant behavioral difficulties, infant mental and motor development, and infant behavior with the observer. Among the findings are the following: (1) depressed mothers' interaction behavior and care of their infants are less adequate than the non-depressed mothers' interaction behavior and care of their infants at 3, 6, and 12 months postpartum; (2) infants' interaction behaviors during feeding and face-to-face interaction with depressed mothers are less adequate than infants' interactions with non-depressed mothers at 3, 6, and 12 months postpartum; (3) mother-infant interactions are less adequate in the depressed mother dyads than the non-depressed dyads at 3, 6, and 12 months postpartum; (4) depressed mothers are less concerned about their infants than non-depressed mothers at 3, 6, and 12 months postpartum; (5) infants of depressed mothers have more behavioral difficulties at 3, 6, and 12 months postpartum than infants of non-depressed mothers; (6) infants of depressed mothers had lower mental and motor development rates at 6 and 12 months postpartum than infants of non-depressed mothers; and (7) infants of non-depressed mothers behaved in a more positive way with the observer than the infants of depressed mothers. (AS)

Development of nanohydrogels as a vehicle for the release of bioactive compounds in food matrices

PhD in Chemical and Biological Engineering

Experimental procedures for the identification of material properties of intervertebal disc - a contribution for the development of biomimetic substitutes for the nucleus pulposus

Tese de Doutoramento em Engenharia Mecânica.

Insights into bacterial colony morphology evolution and diversification during infection development in cystic fibrosis

Tese de Doutoramento em Engenharia Biomédica.

Desarrollo sustentable de geoestructuras compuestas por suelo loéssico compactado mejorado con agregado de materiales estabilizantes. Sustainable development of compacted loess soil geo-structures with addition of stabilizing materials.

Los suelos estabilizados mediante compactación, permiten obtener materiales con ventajas ténicas y economicas en diferentes tipos de obras de ingeniería. Ejemplos de su uso se tiene en bases viales de autopistas, rutas o calles urbanas, pistas de aterrizaje, barreras de contención para enterramientos sanitarios o lagunas de estabilización, apoyos de plateas para fundación de edificios, losas industriales, entre otras aplicaciones. Las fallas en este tipo de construcciones pueden resultar en catástrofes ambientales, sociales y elevadas pérdidas económicas, por lo que resulta de gran importancia optimizar el diseño e incrementar la seguridad de este tipo de construcciones. Las obras con estas características involucran grandes volúmenes y/o superficies que requieren controles sistemáticos durante su desarrollo, a los fines de garantizar el cumplimiento de las propiedades de los materiales establecidos en la etapa de diseño. De esta forma, es necesario contar con ensayos de campo sencillos, confiables y eficientes que permitan identificar propiedades físicas, mecánicas e hidráulicas. Las geoestructuras generadas mediante la compactación del suelo próximo al sector de construcción pueden funcionar adecuadamente, con reducidos costos de material y transporte. Su estabilización puede ejecutarse en forma natural, o con la incorporación de agregados minerales como bentonita, cal o cemento. Estas incorporaciones mejoran las propiedades hidráulicas y mecánicas del material, optimizando el comportamiento requerido para la obra. Para establecer la forma en la que estos minerales modifican el comportamiento del suelo local compactado deben realizarse investigaciones especiales con los materiales involucrados. En el ámbito internacional existen numerosas investigaciones sobre comportamiento de suelos compactados, no obstante, si bien aportan antecedentes para la planificación de estudios locales, sus resultados no pueden trasladarse de manera directa. Las características propias del suelo local constituye la principal variable debido a la diversidad en las propiedades geotécnicas de cada Región. Esta investigación, se focaliza en el empleo de suelos limosos de la formación loéssica de la zona central de Argentina. Los suelos de la llanura cordobesa poseen comportamientos particulares, los cuales son contemplados en los diseños presentados como resutado de las investigaciones internacionales. Esta particularidad se relaciona con su inestabilidad, lo que los clasifica como suelos colapsables. Los resultados obtenidos en este trabajo podrán ser extendidos a una gran superficie de la Provincia de Córdoba y a la Región Pampeana en general, a los fines de establecer recomendaciones de diseño y construcción para la confección de Pliegos de Especificaciones Técnicas de diferentes tipos de obras públicas y privadas. El estudio contempla la ejecución de un plan experimental a escala de laboratorio y campo. Los materiales corresponden a suelo limosos puros, y diferentes agregados tales como bentonita, cal y cemento. Se planifican ensayos para evaluar el desempeño del material, a partir de la confección de muestras preparadas con diferentes condiciones de compactación (energía, humedad y método), y en forma de mezcla con los distintos tipos de agregados. Se realizarán ensayos de permeabilidad en celdas de pared rígida y flexible, junto a ensayos mecánicos de compresión confinada, simple y triaxial. Para el trabajo experimental de campo se prevé la ejecución de terraplenes de prueba instrumentados con tensiómetros e infiltrómetros para evaluar el comportamiento hidraúlico en el tiempo, junto con ensayos de penetración y plato de carga para la caracterización mecánica. En forma conjunta se propone el desarrollo de modelos numéricos de caracterización hidromecánica. Stabilized soils by compaction, produce materials technical and economic advantages in different types of engineering works. For example, road bases in highways, roads or city streets, containment barriers for sanitary landfill or stabilization ponds, foundation support of building, industrial flat, and other applications. Failures can result in environmental catastrophes, social, and economic loss, so it is important to optimize the design and increase the safety of such buildings. These works involve large surfaces that require systematic tests during construction, so it is necessary to have simple field tests, reliable and efficient to identify physical, mechanical and hydraulic properties. The geo-structures generated by local soil compaction have reduced material and transportation costs. Stabilization can be naturally, or with the addition of mineral aggregates as bentonite, lime and cement. These additions improve the hydraulic and mechanical properties of the material. So, special investigations should be conducted with the materials involved. There are many international studies on compacted soils behavior but their results can not be transferred directly due to the particularities of regional soils. For this research silty soils of central Argentina are the main focus. The soils of Córdoba plains are instability, so are classified as collapsible soils. The results obtained in this work may be extended to a large area of the Province of Cordoba and the Pampas region in general, in order to establish design and construction recommendations. The study includes laboratory and field tests. The materials are pure silty soil, and different aggregates such as bentonite, lime and cement. Tests are planned to evaluate the performance. Laboratory includes rigid and flexible wall cells, confined, triaxial and simple compression tests. For field experimental instrumented embankments will be constructed. A numerical hydromechanical model will be developed.