Molecular systems with transition metals : design and properties

[Resumen] El presente trabajo se centra en la síntesis de diferentes carbenos de paladio y plata. Se escogieron como ligandos de partida dos sales de imidazolio: una con un sustituyente metilo (a) y otra con un sustituyente n-butilo (b) que se prepararon agitando a 100ºC una mezcla de los imidazoles correspondientes con dibromometano en tolueno anhidro. Una vez sintetizados ambos ligandos, se hicieron reaccionar con Pd(OAc)2 en DMSO anhidro y atmósfera de argón, empleando técnicas Schlenk y línea de vacío convencional, con el fin deobtener los correspondientes carbenos de paladio (1a y 1b). Se estudió también la reactividad del carbeno de paladio 1b frente a AgNO3, observando que los ligandos bromuro se intercambiaban por ligandos nitrato (3b). Se utilizaron de nuevo ambos ligandos para hacerlos reaccionar con Ag2O en ausencia de luz obteniendo los correspondientes carbenos de plata. Todos los compuestos (excepto el 3b) han sido caracterizados mediante espectroscopia de RMN de 1H y 13C-{1H} y espectrometría de masas; a mayores, el compuesto 2b ha sido caracterizado también mediante medidas de conductividad.[Resumo] O seguinte traballo céntrase na síntese de varios carbenos de paladio e prata. Escolléronse coma ligandos de partida dúas sales de imidazolio: unha cun substituínte metilo (a) e outra cun substituínte n-butilo (b) que foron preparadas axitando a 100ºC unha mestura dos correspondentes imidazois e dibromometano en tolueno anhidro. Unha vez obtidos estes ligandos, fixéronse reaccionar con Pd(OAc)2 en DMSO anhidro e atmosfera de argon, empregando técnicas Schlenk e liña de vacío convencional para obter os carbenos de paladio (1a e 1b). Tamén se estudiou a reactividade do carbeno de paladio 1b con AgNO3, producíndose unha reación de substitución na que os ligandos bromuro e os ligandos nitrato se intercambiaron. Os ligandos de partida fixéronse reaccionar con Ag2O en ausencia de luz para obter os correspondentes carbenos de prata. Tódolos compostos obtidos (a excepción do 3b) foron caracterizados mediante espectroscopia de RMN de 1H y 13C-{1H} e espectrometría de masas. O composto 2b tamén foi caracterizado mediante medidas de condutividade.[Abstract] This project focuses on the synthesis of some palladium and silver carbenes. Two imidazolium salts were chosen as starting ligands: one with methyl substituents (a) and the other one with n-butyl (b). Those ligands were prepared by stirring a mixture of the corresponding imidazols and dibromomethane at 100ºC in anhydrous toluene. Once prepared the ligands, the first step was the synthesis of the palladium carbenes (1a and 1b) by stirring those ligands with Pd(OAc)2 in anhydrous DMSO; that reactions were carried out by using standard Schlenk techniques under an atmosphere of dry argon. Finally, reaction between the palladium carbene and AgNO3 gave the complex 3b after the substitution of the two bromide by nitrate ligands. Silver carbenes were also prepared by stirring the starting imidazolium salts with Ag2O in the dark. All compounds obtained (except 3b) were characterized by 1H, 13C-{1H} and mass spectrometry. The silver carbene 2b was also characterized by conductivity.Traballo fin de grao (UDC.CIE). Química. Curso 2014/201

Structure and Trophic Niches in Mobile Epifauna Assemblages Associated With Seaweeds and Habitats of Syngnathid Fishes in Cíes Archipelago (Atlantic Islands Marine National Park, North West Iberia)

[Abstract] Syngnathids are vulnerable fishes closely associated with seaweeds and seagrass, which provide shelter and food resources. Even though most syngnathids commonly feed on small crustaceans, the feeding regimes may differ depending on the species and prey availability. This is the first monitoring study to explain syngnathid abundances and dietary regimes within macroalgal beds in Cíes Archipelago (Atlantic Islands Marine National Park, North West Iberian Peninsula). We sampled the epifaunal assemblages in seaweed communities dominated by the canopy-forming macroalgae Gongolaria baccata and Codium spp. seasonally during 2 years. The epifaunal structure was mostly represented by harpacticoid copepods, amphipods (especially gammarids) and gastropods. Epifauna exhibited low plant-host specificity and a higher dominance of amphipods on the more structurally complex macroalgae G. baccata. The epifaunal assemblages and syngnathid specimens were assessed for trophic structure using stable isotopes (δ13C and δ15N). The three syngnathids (Hippocampus guttulatus, Syngnathus acus, and Entelurus aequoreus) inhabiting Cíes Archipelago were sympatric. They occupied highly similar trophic positions (TPs), but differed in niche size, in such a way that the snake pipefish E. aequoreus would likely feed on smaller prey. The assessment of the feeding regime in the dominant great pipefish S. acus revealed that amphipods mostly contributed to bulk diet, followed by isopods, carideans, and copepods, whereas mysidaceans were not highly consumed. Seasonal changes in both epifaunal structure and syngnathids abundance confirmed that syngnathids are seasonal residents in Cíes Archipelago, migrating to other areas in autumn when the seaweed cover is drastically reduced and the epifaunal structure modified. This study showed the importance of Gongolaria assemblages in Cíes Archipelago, providing rich dietary sources and potentially contributing to higher abundances and diversity of syngnathids. Ongoing cover reduction in Gongolaria assemblages in certain regions (e.g., Mediterranean) should be considered a potential ecological concern for syngnathids and accompanying fauna, requiring further investigations.This study was financially supported by the Spanish Government with project Hippoparques (Ref. 1541S/2015, Organismo Autónomo de Parques Nacionales de España, Ministerio para la Transición Ecológica y Reto Demográfico, MITECO, Spain

Análisis de una estrategia con opciones. Short Strip Strangle sobre Gas Natural

[Resumen]: Este trabajo pretende ampliar los conocimientos básicos sobre opciones financieras, centrándose en una estrategia, la Short Strip Strangle, analizándola de manera teórica y práctica sobre las acciones de Gas Natural. Se estudian en profundidad las diferentes clases de opciones financieras, sus características, posiciones y, concretamente, el cálculo de la prima (precio de la opción) y su sensibilidad respecto a las variables que la componen. El Short Strip Strangle combina tres opciones, dos de ellas de venta y una de compra, y todas con idéntica posición, situación y fecha de vencimiento, siendo adecuada para activos que no sufran elevadas variaciones en su precio. En cuanto a la parte práctica, se ha realizado una simulación en hoja de cálculo para obtener los resultados y medidas estadísticas de la estrategia a lo largo de un horizonte temporal. Se han analizado las sensibilidades de las variables que afectan al precio de la estrategia con el fin de elaborar un contraste de hipótesis. Además, se ha realizado también en la hoja de cálculo un modelo de valoración que tiene como objetivo realizar un análisis de los datos obtenidos. Cabe destacar que habría sido viable la implantación de dicha estrategia para Gas Natural, ya que se lograría la máxima ganancia en la mayor parte del horizonte temporal. Esto se ha debido a la escasa fluctuación que ha sufrido el precio del activo. Para finalizar, se puede concluir diciendo que la realización del trabajo ha facilitado el manejo de la hoja de cálculo, ha servido también para adquirir conocimientos financieros específicos, mejorar la expresión escrita, aprender el manejo de bibliografía especializada, adquirir un vocabulario específico de inglés financiero y para relacionar cuestiones teóricas con un entorno práctico y real, interpretando datos relevantes y desarrollando la capacidad de emitir juicios de valor y conclusiones con fundamentos.[Abstract]: This paper aims to expand basic knowledge about financial options by focusing on a strategy, the Short Strip Strangle, applying it to the stocks of Gas Natural in a theoretical and practical way. The different types of financial options, their characteristics, positions, and the calculation of the premium (price of the option) and its sensitivity to the variables that compose it, are studied. The Short Strip Strangle combines three options (two put and one call), all with identical position, situation and expiration date, being suitable for assets that do not undergo high variations in their price. As for the practical part, a simulation has been carried out in a spreadsheet to obtain the results and statistical measures of the strategy throughout the time horizon. The sensitivities of the variables that alter the price of the strategy have been analysed to elaborate a hypothesis test. In addition, it has also been made in the spreadsheet a valuation model that helps in performing an analysis of the obtained data. It should be noted that it would have been viable the implementation of this strategy for Gas Natural since the maximum profit would be achieved in most part of the time horizon. This has been due to the limited fluctuation that the price of the asset has experienced. To conclude, we can say that the execution of the paper has facilitated the use of the spreadsheet, it has also been useful for acquiring specific financial knowledge, improving written expression, learning the utilization of specialised bibliography, acquiring a specific vocabulary of financial English and connecting theoretical issues with a practical and real environment, interpreting relevant data and developing the ability to make value judgments and reasoned conclusions.Traballo fin de grao (UDC.ECO). ADE. Curso 2016/201

Analysis of polycyclic aromatic hydrocarbons in atmospheric particulate samples by microwaveassisted extraction and liquid chromatography

A methodology based on microwave-assisted extraction (MAE) and LC with fluorescence detection (FLD) was investigated for the efficient determination of 15 polycyclic aromatic hydrocarbons (PAHs) regarded as priority pollutants by the US Environmental Protection Agency and dibenzo(a,l)pyrene in atmospheric particulate samples. PAHs were successfully extracted from real outdoor particulate matter (PM) samples with recoveries ranging from 81.4±8.8 to 112.0±1.1%, for all the compounds except for naphthalene (62.3±18.0%) and anthracene (67.3±5.7%), under the optimum MAE conditions (30.0 mL of ACN for 20 min at 110ºC). No clean-up steps were necessary prior to LC analysis. LOQs ranging from 0.0054 ng/m3 for benzo( a)anthracene to 0.089 ng/m3 for naphthalene were reached. The validated MAE methodology was applied to the determination of PAHs from a set of real world PM samples collected in Oporto (north of Portugal). The sum of particulate-bound PAHs in outdoor PM ranged from 2.5 and 28 ng/m3.http://recipp.ipp.pt/handle/10400.22/289

Análisis de una estrategia con opciones. Short Strip Strangle sobre Gas Natural

[Resumen]: Este trabajo pretende ampliar los conocimientos básicos sobre opciones financieras, centrándose en una estrategia, la Short Strip Strangle, analizándola de manera teórica y práctica sobre las acciones de Gas Natural. Se estudian en profundidad las diferentes clases de opciones financieras, sus características, posiciones y, concretamente, el cálculo de la prima (precio de la opción) y su sensibilidad respecto a las variables que la componen. El Short Strip Strangle combina tres opciones, dos de ellas de venta y una de compra, y todas con idéntica posición, situación y fecha de vencimiento, siendo adecuada para activos que no sufran elevadas variaciones en su precio. En cuanto a la parte práctica, se ha realizado una simulación en hoja de cálculo para obtener los resultados y medidas estadísticas de la estrategia a lo largo de un horizonte temporal. Se han analizado las sensibilidades de las variables que afectan al precio de la estrategia con el fin de elaborar un contraste de hipótesis. Además, se ha realizado también en la hoja de cálculo un modelo de valoración que tiene como objetivo realizar un análisis de los datos obtenidos. Cabe destacar que habría sido viable la implantación de dicha estrategia para Gas Natural, ya que se lograría la máxima ganancia en la mayor parte del horizonte temporal. Esto se ha debido a la escasa fluctuación que ha sufrido el precio del activo. Para finalizar, se puede concluir diciendo que la realización del trabajo ha facilitado el manejo de la hoja de cálculo, ha servido también para adquirir conocimientos financieros específicos, mejorar la expresión escrita, aprender el manejo de bibliografía especializada, adquirir un vocabulario específico de inglés financiero y para relacionar cuestiones teóricas con un entorno práctico y real, interpretando datos relevantes y desarrollando la capacidad de emitir juicios de valor y conclusiones con fundamentos.[Abstract]: This paper aims to expand basic knowledge about financial options by focusing on a strategy, the Short Strip Strangle, applying it to the stocks of Gas Natural in a theoretical and practical way. The different types of financial options, their characteristics, positions, and the calculation of the premium (price of the option) and its sensitivity to the variables that compose it, are studied. The Short Strip Strangle combines three options (two put and one call), all with identical position, situation and expiration date, being suitable for assets that do not undergo high variations in their price. As for the practical part, a simulation has been carried out in a spreadsheet to obtain the results and statistical measures of the strategy throughout the time horizon. The sensitivities of the variables that alter the price of the strategy have been analysed to elaborate a hypothesis test. In addition, it has also been made in the spreadsheet a valuation model that helps in performing an analysis of the obtained data. It should be noted that it would have been viable the implementation of this strategy for Gas Natural since the maximum profit would be achieved in most part of the time horizon. This has been due to the limited fluctuation that the price of the asset has experienced. To conclude, we can say that the execution of the paper has facilitated the use of the spreadsheet, it has also been useful for acquiring specific financial knowledge, improving written expression, learning the utilization of specialised bibliography, acquiring a specific vocabulary of financial English and connecting theoretical issues with a practical and real environment, interpreting relevant data and developing the ability to make value judgments and reasoned conclusions.Traballo fin de grao (UDC.ECO). ADE. Curso 2016/201

Levels and Sources of Atmospheric Particle-Bound Mercury in Atmospheric Particulate Matter (PM₁₀) at Several Sites of an Atlantic Coastal European Region

[Abstract] Atmospheric particle-bound mercury (PHg) quantification, at a pg m⁻³ level, has been assessed in particulate matter samples (PM₁₀) at several sites (industrial, urban and sub-urban sites) of Atlantic coastal European region during 13 months by using a direct thermo-desorption method. Analytical method validation was assessed using 1648a and ERM CZ120 reference materials. The limits of detection and quantification were 0.25 pg m⁻³ and 0.43 pg m⁻³, respectively. Repeatability of the method was generally below 12.6%. PHg concentrations varied between 1.5–30.8, 1.5–75.3 and 2.27–33.7 pg m⁻³ at urban, sub-urban and industrial sites, respectively. PHg concentration varied from 7.2 pg m⁻³ (urban site) to 16.3 pg m⁻³ (suburban site) during winter season, while PHg concentrations varied from 9.9 pg m⁻³ (urban site) to 19.3 pg m⁻³ (suburban site) during the summer. Other trace elements, major ions, black carbon (BC) and UV-absorbing particulate matter (UV PM) was also assessed at several sites. Average concentrations for trace metals (Al, As, Bi, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Si, Sr, V and Zn) ranged from 0.08 ng m⁻³ (Bi) at suburban site to 1.11 µg m⁻³ (Fe) at industrial site. Average concentrations for major ions (including Na⁺, K⁺, Ca²⁺, NH₄⁺, Mg²⁺, Cl⁻, NO₃⁻ and SO₄²⁻) ranged from 200 ng m⁻³ (K⁺) to 5332 ng m⁻³ (SO₄²⁻) at urban site, 166 ng m⁻³ (Mg²⁺) to 4425 ng m⁻³ (SO₄²⁻) at suburban site and 592 ng m⁻³ (K⁺) to 5853 ng m⁻³ (Cl⁻) at industrial site. Results of univariate analysis and principal component analysis (PCA) suggested crustal, marine and anthropogenic sources of PHg in PM₁₀ at several sites studied. Toxicity prediction of PHg, by using hazard quotient, suggested no non-carcinogenic risk for adults.This work was supported by Xunta de Galicia (Programa de Consolidación y Estructuración de Unidades de Investigación Competitivas ref: ED431C 2017/28-2017-2020) FEDER-MINECO (UNLC15-DE-3097, financed together (80/20%) with Xunta de Galicia and Ministerio de Ciencia, Innovación y Universidades (Programa Estatal de I+D+i Orientada a los Retos de la Sociedad ref: RTI2018-101116-B-I00 (MCIU/AEI/FEDER, UE). We are grateful to Alicia Cantarero-Roldán (SAI-University of A Coruña) for ICP-MS technical support. M. Fernández-Amado appreciates the Ministerio de Ciencia, Innovación y Universidades support (PTA2017-13607-I). The authors would like to thank P. Esperón (PTA2013-8375-I) for her support.Xunta de Galicia; ED431C 2017/28-2017-202

Treatment of tobacco dependence in a smoker who has had lung cancer in the past

La relación entre fumar y el cáncer de pulmón está bien establecida. La principal causa conocida del cáncer de pulmón es el consumo de tabaco, que es el responsable del 90% de los casos de cáncer de pulmón. En el presente artículo presentamos el caso de un fumador que ha tenido un cáncer de pulmón en el pasado (superviviente de doce años de un adenocarcinoma de pulmón), que demanda tratamiento para dejar de fumar por el miedo a padecer otro cáncer de pulmón y a morir por las enfermedades relacionadas con el consumo de tabaco. Se le aplicó el tratamiento psicológico cognitivo-conductual “Programa Para Dejar de Fumar”. Se describe la evaluación, tratamiento y seguimientos realizados durante doce meses. El resultado del tratamiento muestra que es posible dejar de fumar y mantenerse abstinente a lo largo de un año. También manifiesta claros beneficios del abandono del tabaco a nivel físico, psicológico y en su aumento de la calidad de vida relacionada con la saludThe relationship between smoking and lung cancer is well established. The leading known cause of lung cancer is the consumption of tobacco, which is responsible for 90% of lung cancer cases. In this article we present the case of a smoker who has had lung cancer in the past (survivor of lung adenocarcinoma a total of twelve years), who requires treatment to stop smoking, motivated by the fear of suffering from lung cancer again and dying from diseases related to the consumption of tobacco. He was given the cognitive-behavioral psychological treatment “Smoking Cessation Program.” It describes the assessment, treatment and subsequent follow-ups over twelve months. The result of this treatment shows that it is possible to quit smoking and remain abstinent from it during a year. This case highlights the physical and psychological benefits of quitting smoking, as well as the increase of healthrelated quality of lifeS

Evolution of Gaseous and Particulate Pollutants in the Air: What Changed after Five Lockdown Weeks at a Southwest Atlantic European Region (Northwest of Spain) Due to the SARS-CoV-2 Pandemic?

[Abstract] Due to the exponential growth of the SARS-CoV-2 pandemic in Spain (2020), the Spanish Government adopted lockdown measures as mitigating strategies to reduce the spread of the pandemic from 14 March. In this paper, we report the results of the change in air quality at two Atlantic Coastal European cities (Northwest Spain) during five lockdown weeks. The temporal evolution of gaseous (nitrogen oxides, comprising NOₓ, NO, and NO₂; sulfur dioxide, SO₂; carbon monoxide, CO; and ozone, O₃) and particulate matter (PM₁₀; PM₂․₅; and equivalent black carbon, eBC) pollutants were recorded before (7 February to 13 March 2020) and during the first five lockdown weeks (14 March to 20 April 2020) at seven air quality monitoring stations (urban background, traffic, and industrial) in the cities of A Coruña and Vigo. The influences of the backward trajectories and meteorological parameters on air pollutant concentrations were considered during the studied period. The temporal trends indicate that the concentrations of almost all species steadily decreased during the lockdown period with statistical significance, with respect to the pre-lockdown period. In this context, great reductions were observed for pollutants related mainly to fossil fuel combustion, road traffic, and shipping emissions (−38 to −78% for NO, −22 to −69% for NO₂, −26 to −75% for NOₓ, −3 to −77% for SO₂, −21% for CO, −25 to −49% for PM₁₀, −10 to −38% for PM₂․₅, and −29 to −51% for eBC). Conversely, O₃ concentrations increased from +5 to +16%. Finally, pollutant concentration data for 14 March to 20 April of 2020 were compared with those of the previous two years. The results show that the overall air pollutants levels were higher during 2018–2019 than during the lockdown period.This work was supported by Ministerio de Ciencia, Innovación y Universidades (MCIU), Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER) (Programa Estatal de I+D+i Orientada a los Retos de la Sociedad, ref: RTI 2018-101116-B-I00), Xunta de Galicia (Programa de Consolidación y Estructuración de Unidades de Investigación Competitivas ref: ED431C 2017/28-2017-2020) and FEDER-MINECO (UNLC15-DE-3097, financed together (80/20%) with Xunta de Galicia). Joel Sánchez-Piñero acknowledges the Xunta de Galicia and the European Union (European Social Fund-ESF) for a predoctoral grant (ED481A-2018/164). María Fernández-Amado acknowledges the Ministerio de Ciencia, Innovación y Universidades (PTA2017-13607-I)

Estudio del perfil de egresadas de la titulación de Ingeniería de Minas por la Universidad de Vigo. Promociones 1997-2013

[RESUMEN] El ámbito laboral de la minería está tradicionalmente ligado al género masculino, justificándose esta realidad, durante siglos, por la dureza de las condiciones de trabajo y la peligrosidad inherente a las labores mineras. Esta situación se constató tradicionalmente en las minas de nuestro país, y aún hoy en día perdura en el ámbito de la operación minera, apreciándose sin embargo una presencia cada vez mayor de las mujeres en puestos técnicos. Con el fin de refrendar esta evolución con datos, se presenta en este trabajo el estudio del perfil laboral de las egresadas de las primeras 17 promociones de la titula ción de Ingeniería de Minas, implantada en la Universidad de Vigo en el curso 1992/1993. Este estudio se aborda como un objetivo clave en la ETSI de Minas de Vigo, ya que permite conocer el grado y el ámbito de inserción de sus egresadas en el mundo laboral, contribuyendo así a la mejora continua de los planes de estudio de sus dos grados implantados actualmente en la ETSI de Minas de Vigo (Grado en Ingeniería de la Energía y Grado en Ingeniería de los Recursos Mineros y Energéticos), herencia directa de la titulación de Ingeniería de Minas en proceso de extinción