Master of Science

thesisElectrochemical capacitors, or "supercapacitors", are an electrochemical energy storage technology with high-power density and long cycle life compared to batteries. Supercapacitors have many promising applications in electric vehicles, renewable energy storage, consumer electronics, environmental sensors, biomedical implants, and grid energy storage. Conductive polymers are a material of interest for supercapacitor energy storage because of their ability to store energy by both electric double layer capacitance and "pseudocapacitance" (surface reduction-oxidation reactions). Polypyrrole is a widely used conductive polymer for supercapacitor electrodes, as well as in lithium-ion batteries. For applications in environmental sensors, transient electronics, and implantable devices, it is necessary to find supercapacitor electrode materials that are easily biodegradable. A variation of polypyrrole exhibiting methyl carboxylate side chains, which we call "MPC polymer," is presented in this thesis as a dissolvable supercapacitor electrode. It is, to the best of our knowledge, introduced for the first time as a dissolvable electrochemical energy storage material. The supercapacitor characteristics of MPC polymer are characterized for planar electrodes as well as a nanocellulose-based composite. The MPC polymer is found to have capacitance, cycle life, and impedance characteristics comparable to state-of-the-art polypyrrole

Modeling Ovoproduct Spoilage with Red Led Light

Heat-treatment of ovoproducts is often required to ensure microbial safety. However, it has been shown that in most microbial species slow heating, or heat shocks may induce a higher heat resistance, that means that it is not possible to remove the microbial flora completely. These microorganisms produce on ovoproducts spoilage especially when the cold chain is broken along the transportation and/or storage. As a result, the life span for the product is shortened. The microbial activity inside the product causes changes in several physical properties, which can be supervised using optical methods. The aim of this work is to monitor the sigmoid behaviour underlying the ovoproduct evolution and spoilage by means of red LED light. For two commercial types of liquid and pasteurized egg white, storage at 9°C, an average correlation of r=0.94 has been found between microorganism growth and mean grey level of LED light passing though the sample. The results show that it is possible to develop very simple predictive models taking into account only one optical parameter corre¬sponding to a single LED

Supervisión de la degradación de ovoproducto mediante diodos emisores de luz

La extrema sensibilidad de los ovoproductos al deterioro microbiano hace necesaria la aplicación de un tratamiento térmico que asegure su inocuidad. El hecho de que el tratamiento térmico no asegure la completa erradicación de la flora microbiana junto con la falta de mantenimiento de la cadena de frío a lo largo de la distribución y/o conservación del mismo limita y acorta la vida útil del producto. La degradación microbiana del ovoproducto afecta a ciertas propiedades físicas del mismo cuya alteración puede ser objeto de supervisión mediante técnicas ópticas siendo el objetivo de este trabajo la realización de un estudio preliminar para la supervisión de la degradación de ovoproducto mediante LED con el objeto de hacer una propuesta de implantación en laboratorios de calidad en la industria. Los resultados muestran que en clara líquida pasteurizada el aumento del contenido microbiano a lo largo del tiempo de almacenamiento se correlaciona (con valores de hasta r = 0.97) con el incremento en el nivel de intensidad lumínica detectado en las muestras. En la yema a partir de niveles altos de concentración de microorganismos los fenómenos de turbidez y gelificación se identifican con una disminución en los valores de los parámetros ópticos considerados

Supervision of ovoproducts spoilage with red led light

Heat-treatment of ovoproducts is often required to ensure microbial safety. However, it has been shown that in most microbial species slow heating, or heat shocks may induce a higher heat resistance, that means that it is not possible to remove the microbial flora completely. These microorganisms produce on ovoproducts spoilage especially when the cold chain is broken along the transportation and/or storage. As a result, the life span for the product is shortened. The microbial activity inside the product causes changes in several physical properties, which can be supervised using optical methods. The aim of this work is to monitor the sigmoid behaviour underlying the ovoproduct evolution and spoilage by means of red LED light. For two commercial types of liquid and pasteurized egg white, storage at 9ºC, an average correlation of r=0.94 has been found between microorganism growth and images mean grey level of LED light passing though the sample. The results show that it is possible to develop very simple predictive models taking into account only one optical parameter corresponding to a single LED

Prenatal Insecticide Exposures and Birth Weight and Length among an Urban Minority Cohort

We reported previously that insecticide exposures were widespread among minority women in New York City during pregnancy and that levels of the organophosphate chlorpyrifos in umbilical cord plasma were inversely associated with birth weight and length. Here we expand analyses to include additional insecticides (the organophosphate diazinon and the carbamate propoxur), a larger sample size (n = 314 mother–newborn pairs), and insecticide measurements in maternal personal air during pregnancy as well as in umbilical cord plasma at delivery. Controlling for potential confounders, we found no association between maternal personal air insecticide levels and birth weight, length, or head circumference. For each log unit increase in cord plasma chlorpyrifos levels, birth weight decreased by 42.6 g [95% confidence interval (CI), −81.8 to −3.8, p = 0.03] and birth length decreased by 0.24 cm (95% CI, −0.47 to −0.01, p = 0.04). Combined measures of (ln)cord plasma chlorpyrifos and diazinon (adjusted for relative potency) were also inversely associated with birth weight and length (p < 0.05). Birth weight averaged 186.3 g less (95% CI, −375.2 to −45.5) among newborns with the highest compared with lowest 26% of exposure levels (p = 0.01). Further, the associations between birth weight and length and cord plasma chlorpyrifos and diazinon were highly significant (p ≤ 0.007) among newborns born before the 2000–2001 U.S. Environmental Protection Agency’s regulatory actions to phase out residential use of these insecticides. Among newborns born after January 2001, exposure levels were substantially lower, and no association with fetal growth was apparent (p > 0.8). The propoxur metabolite 2-isopropoxyphenol in cord plasma was inversely associated with birth length, a finding of borderline significance (p = 0.05) after controlling for chlorpyrifos and diazinon. Results indicate that prenatal chlorpyrifos exposures have impaired fetal growth among this minority cohort and that diazinon exposures may have contributed to the effects. Findings support recent regulatory action to phase out residential uses of the insecticides

Ovoproductos

La extrema sensibilidad de los ovoproductos al deterioro microbiano hace necesaria la aplicacion de un tratamiento termico que asegure su inocuidad. El hecho de que el tratamiento termico no asegure la completa erradicacion de la flora microbiana junto con la falta de mantenimiento de la cadena de fn'o a lo largo de la distribucion y/o conservacion del mismo limita y acorta la vida util del producto. La degradacion microbiana del ovoproducto afecta a ciertas propiedades ffsicas del mismo cuya alteration puede ser objeto de supervision mediante tecnicas opticas siendo el objetivo de este trabajo la realization de un estudio preliminar para la supervision de la degradacion de ovoproducto mediante LED con el objeto de hacer una propuesta de implantation en laboratories de calidad en la industria. Los resultados muestran que en clara liquida pasteurizada el aumento del contenido microbiano a lo largo del tiempo de almacenamiento se correlaciona (con valores de hasta r = 0.97) con el incremento en el nivel de intensidad luminica detectado en las muestras, siendo posible establecer modelos sencillos de prediction de la carga microbiana a traves de este para metro optico y empleando la information correspondiente a un unico LED. - Heat-treatment of ovoproducts is often required to ensure microbial safety. However, it has been shown that in most microbial species slow heating, or heat shocks may induce a higher heat resistance, that means that it is not possible to remove the microbial flora completely. These microorganisms produce ovoproducts spoilage especially when the cold chain is broken along the transport and/or storage. As result, the useful life for the product is shorten. The microbial activity in the product changes several physical properties which can be supervised using optical methods, so the goal of this work is to carry out a prospective study for the supervision of ovoproduct spoilage with scatter red LED light. For liquid and pasteurizated white egg it has been found a correlation (r=0.97) between microorganism growth and grey level of LED light passing thought out the sample

Diseño y optimización de sistemas de transformación y conservación de naranja variedad “Canoneta” de la Serra Nord mallorquina para obtención de naranja IV gama

Este trabajo muestra el efecto de diferentes tipos de procesado sobre la vida útil de naranjas mínimamente procesadas de la variedad “Canoneta”. Las naranjas peladas de manera mecánica o semimanual fueron envasadas en dos atmósferas (vacío parcial y 20% CO2+ 80% N2) y se almacenaron durante 10 días a 4ºC y a 8ºC. Los análisis sensoriales, microbiológicos y físicoquímicos identificaron el pelado semi-manual como el menos idóneo de los métodos de pelado y se estableció 7 días como la vida útil máxima para un producto aceptable desde el punto de vista sensorial

Stenocarpella maydis and Sporisorium reilianum: Two Pathogenic Fungi of Maize

Stenocarpella maydis and Sporisorium reilianum are phytopathogenic fungi that cause white rot in corn cob and head smut in maize (Zea mays L.) respectively, diseases that are spread worldwide and cause many economic losses. In this chapter the characteristics of the above diseases, such as their life cycle, pathogenicity factors, control methods, as well as the biotechnological potential of the fungi involved in this processes are described, specifically in connection to their extracellular enzymes

Nuevas metodologías con un enfoque interdisciplinar en la docencia de asignaturas relacionadas con la Tecnología de Alimentos

El objeto de este proyecto es compartir metodologías docentes y técnicas de evaluación desde un enfoque pluridisciplinar en la Universidad Politécnica de Madrid (U.P.M.), implicando a 6 asignaturas con un nexo común. Todas ellas están relacionadas con el procesado de alimentos en la Industria Agroalimentaria, desde la materia prima hasta el producto final. Para ello se recurre al empleo de metologías de distinta naturaleza, tanto presenciales como no presenciales. El aspecto más novedoso es la introducción de las pruebas de análisis sensorial e instrumental de los alimentos como nueva metodología docente. El empleo de ambos tipos de pruebas permite, de forma complementaria, evaluar la calidad de los alimentos y los cambios en sus propiedades inducidos por la modificación de parámetros del procesado y/o cambios en la formulación de las materias primas. El empleo de las pruebas de análisis sensorial permite además al alumno PERCIBIR dichos cambios, de forma que se afianza su aprendizaj

Patterns of Sedentary Behavior and Mortality in U.S. Middle-Aged and Older Adults: A National Cohort Study

Background: Excessive sedentary time is ubiquitous in Western societies. Previous studies have relied on self-reporting to evaluate the total volume of sedentary time as a prognostic risk factor for mortality and have not examined whether the manner in which sedentary time is accrued (in short or long bouts) carries prognostic relevance. Objective: To examine the association between objectively measured sedentary behavior (its total volume and accrual in prolonged, uninterrupted bouts) and all-cause mortality. Design: Prospective cohort study. Setting: Contiguous United States. Participants: 7985 black and white adults aged 45 years or older. Measurements: Sedentary time was measured using a hip-mounted accelerometer. Prolonged, uninterrupted sedentariness was expressed as mean sedentary bout length. Hazard ratios (HRs) were calculated comparing quartiles 2 through 4 to quartile 1 for each exposure (quartile cut points: 689.7, 746.5, and 799.4 min/d for total sedentary time; 7.7, 9.6, and 12.4 min/bout for sedentary bout duration) in models that included moderate to vigorous physical activity. Results: Over a median follow-up of 4.0 years, 340 participants died. In multivariable-adjusted models, greater total sedentary time (HR, 1.22 [95% CI, 0.74 to 2.02]; HR, 1.61 [CI, 0.99 to 2.63]; and HR, 2.63 [CI, 1.60 to 4.30]; P for trend < 0.001) and longer sedentary bout duration (HR, 1.03 [CI, 0.67 to 1.60]; HR, 1.22 [CI, 0.80 to 1.85]; and HR, 1.96 [CI, 1.31 to 2.93]; P for trend < 0.001) were both associated with a higher risk for all-cause mortality. Evaluation of their joint association showed that participants classified as high for both sedentary characteristics (high sedentary time [≥12.5 h/d] and high bout duration [≥10 min/bout]) had the greatest risk for death. Limitation: Participants may not be representative of the general U.S. population. Conclusion: Both the total volume of sedentary time and its accrual in prolonged, uninterrupted bouts are associated with all-cause mortality, suggesting that physical activity guidelines should target reducing and interrupting sedentary time to reduce risk for death