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Prensa en clase
No full textEn este proyecto se pretende fomentar la lectura
de prensa continuada por parte de los alumnos a la vez que se establece
un vínculo entre las noticias publicadas y los contenidos de las asignaturas.
Concretamente, se va a llevar a cabo en las asignaturas Proyectos en
Química –4o curso del Grado en Química y de la doble Química y
Bioquímica - y Fundamentos de Ingeniería Ambiental/Fundamentals of
Environmental Engineering de 1er curso de Ciencias Ambientales y 3er
curso de la doble Biología y Ciencias Ambientales
Química Farmacéutica I. Anestésicos. Reacción de acetilación: Procedimiento sintético
No full textTemas de la Asignatura Química Farmacéutica I de 3º de Farmacia
Formación transversal sobre la industria de la moda para los alumnos de Química
No full textLa industria de la moda, o la industria textil en un concepto más amplio, supone un importante impacto ambiental derivado de transformación de materias primas y residuos producidos al final de la vida útil de los productos. Una de las disciplinas que pueden ayudar a optimizar los procesos y minimizar los residuos es la Química, que, con el conocimiento de reacciones, procesos industriales y alternativas, puede mitigar este impacto negativo.
Hasta el momento, los alumnos de Química no estudiaban la fuerte vinculación entre sector textil y Química. El proyecto que se presenta se basa en la metodología del aprendizaje integrado. Concretamente, pretende dotar al alumno de Química de la capacidad de desarrollar un proyecto interdisciplinar basado en la industria textil, especialmente en aquellos aspectos de dicha industria que convergen en el ámbito químico, como es el tema de fibras tanto artificiales como sintéticas, tintes y pigmentos, acabados, etc. Asimismo, también pretende ser una herramienta de concienciación ambiental y social, que se puede encuadrar en la Estrategia 2025 de la Universidad de Navarra. Dicha estrategia lleva por lema “Universidad y Sostenibilidad” y cuyo objetivo es contribuir a la resolución de los desafíos que la sociedad plantea mediante su trabajo investigador, docente y asistencial, en colaboración con otras personas e instituciones. En un sentido más amplio, el proyecto propuesto cuadra con la Agenda 2030 para el Desarrollo Sostenible, suscrita por la Asamblea General de las Naciones Unidas, y sus 17 Objetivos de Desarrollo Sostenible (ODS).
Basado en todo lo anterior, se plantea un proyecto multidisciplinar que vincula diferentes asignaturas del 4º curso del grado en Química a los contenidos de un curso de posgrado relacionado con la sostenibilidad en la industria de la moda. Supone la estrecha colaboración entre la Facultad de Ciencias, donde se imparte el grado en Química, y el Instituto Superior de Estudios en Moda -ISEM-, ambos centros pertenecientes a la Universidad de Navarra
Química Farmacéutica I. Tema 6. Farmacología del dolor
No full textTemas de la Asignatura Química Farmacéutica I de 3º de Farmacia
Hard materials free of WC and Co for tribological applications: WB4 ultrahard ceramics and TiC cermets.
No full textThis thesis addresses the problem of finding wear-resistant materials that could substitute WC-Co alloys in specific tribological applications. The main challenge lies in the versatility of these alloys to cover a broad range of physicochemical properties by merely varying the WC/Co ratio and the grain size of the ceramic phase. This is not possible when using other combinations of ceramic and metal since, in general, the interfacial strength is lower than that observed between tungsten carbide and cobalt. The need to find alternatives to the WC-Co system arises from the strategic value of these raw materials, currently controlled by the People's Republic of China. Furthermore, batteries developed for electric vehicle motors contain a significant amount of cobalt, exacerbating the supply risk of this metal in the European Union. This thesis proposes the development of two very different materials that could replace WC-Co alloys in two sectors of interest: materials used in shot blasting or water jet cutting and guiding systems in hot rolling equipment. For the former, tungsten tetraboride, a new metallic boride with hardness exceeding 40 GPa, has been considered, and for the latter, the development of cermets based on titanium carbide and iron is suggested. The first set of results in this thesis focuses on the development of ultrahard materials based on tungsten tetraboride that could substitute WC binderless carbides in applications requiring high erosive wear resistance (i.e., nozzles for water cutting or shot peening). This objective has been addressed applying hot isostatic pressing (HIP) technique to both as-received WB4-B and WB4-B-Ta powder mixtures. Overstoichiometric B/W ratios and Ta additions were selected for their effect on stabilizing the ultrahard WB4 phase, as described in the literature. This is a difficult task, since the stability of WB4 requires a boron activity much higher than that corresponding to a B/W ratio of 4. Porosity removal was more efficient in the alloy containing metallic tantalum, achieving near full density at temperatures 300 ºC lower than those reported so far for these materials. The WB4 phase is better stabilized by HIPing at 1350 ºC than at 1100 ºC. This is due to the formation of TaB2, which at 1100 ºC, likely occurs by direct reaction between metallic Ta and the surrounding WB4 particles. At 1350 ºC, diffusion is enhanced and the reaction between free B and Ta particles becomes more probable. The nanohardness of WB4 HIPed specimens reaches 43 GPa, that is, 43 % higher than the highest reported for binderless WC. Indentation toughness is similar to that reported for WC-1 wt. % Mo2C (5.6 and 6.6 MPa·m1/2 respectively). Contrary to that reported by other authors, it has been confirmed that metallic Ta additions enhance the decomposition of tungsten tetraboride into tungsten diboride and Ta-rich borides. According to XRD data and SEM analyses, this phenomenon is more pronounced when HIPing is made at lower temperatures, which is against thermodynamic calculations. This is probably related to kinetic effects, since direct reaction between free B regions and metallic Ta powders requires higher mobility than that observed after HIPing at 1100 ºC. The latest results were obtained by investigating the possibility of producing cermets based on WB4-B-TaB2 powders with Ni additions. It was confirmed that densification of WB4-B-TaB2 is notably activated by Ni additions, reducing by 250 ºC the temperature needed for porosity removal. This is likely due to the formation of a liquid phase above 1007 ºC, compatible with the formation of Ni4B3 and NiB borides on heating. These borides are mainly formed by direct reaction between free B and Ni powders, although some boron could also be available from the partial decomposition of WB4 into W2B5. As no metallic nickel remains after HIPing, the toughness of these composites is very low. On the other hand, strength and toughness of WB4-B-TaB2-Ni alloys are notably improved by TiAl3 and Zr additions. Although Ni containing borides are still present in these alloys, there are also Ni-Al rich phases free of boron which provide a significant toughening effect, as confirmed by indentation cracking. These B-free regions remain unbroken joining the crack lips, although it progresses forward through boride grains. Highest fracture strength values correspond to the combined addition of TiAl3 and Zr powders to WB4-B-TaB2-Ni mixtures (≈ 1 GPa). However, in these materials WB4 grains are fully decomposed into a combination of mixed borides. The challenge associated with manufacturing components from TiC-Fe alloys for steel wire guiding in hot rolling equipment lies in their difficulty to be sintered. In this thesis, fully dense TiC-Fe-Cr-Mo based cermets have been sintered from two different alloys: TiC-Fe-Cr3C2-Mo and TiC-Fe-Cr3C2-Mo2C. It has been investigated the effect of metallic molybdenum or molybdenum carbide additions as wetting activators during liquid phase sintering of TiC-Fe powder mixtures. The addition of molybdenum in these systems is carried out to increase the wetting properties by the formation of the so-called core-rim structures, typical of TiC based cermets. These structures are formed by Ti-rich cores (α’ phase) surrounded by shells (α’’ phase) comprised of complex cubic carbides. Chromium was added into the powder mixtures as carbide, since its oxidation resistance is higher than that of metallic Cr and it is brittle enough to distributed homogeneously with the other constituents of the alloy during the mixing and milling process. In addition, the effect of pressure in the furnace chamber on porosity removal and on the formation of surface compositional gradients has also been explored. Results show that densification of TiC-Fe-Cr-Mo cermets is strongly affected by the selection of starting powders and the vacuum condition used during the sintering cycle. Liquid phase sintering is enhanced by using a lower pressure during the heating ramp of the sintering cycle (i.e., 10-5 mbar vs. 10-2 mbar), confirming that carbothermal reduction of the most stable oxides present in these materials requires very low oxygen activity. The massive evaporation of the binder phase observed at 10-5 mbar is avoided by injecting Ar in the sintering chamber above 1300 ºC. However, cermets sintered in this condition present some residual porosity due to Ar entrapment. Cermets with Mo2C additions lead to higher densities than those based on metallic Mo. This is likely due to the finer particle size of the former which likely accelerate diffusion kinetics associated to the formation of “core-rim” structures. Carbon losses after sintering are also higher in compositions based on Mo2C additions, suggesting that these powders enhance carbothermal reduction of oxides present in the surface of starting powders. Significant migration of the binder phase towards the cermet surface is observed in TiC-Fe-Cr-Mo cermets when sintering is carried out at low vacuum levels (i. e., 10-2 mbar). Compositional gradients produced by this migration are likely related to oxidation occurring once the closed porosity state is reached. Best results are obtained with 10-5 mbar of pressure and injection of 1.2 bar of Ar at 1300 ºC (named HV-1 cycle) and with 10-2 mbar of pressure without Ar injection (named LV-2 cycle). These two cycles lead to materials with low porosity levels, low mass losses and homogeneous microstructures. These materials achieve significant hardening through air-quenching from 950 ºC, resulting in properties suitable for hot wear applications. Another key aspect of TiC-Fe-Cr-Mo based cermets is the carbon partitioning between the ceramic and the metallic phase during sintering, since the latter is susceptible to hardening by austenitizing and quenching. It has been found that relatively low differences in the carbon content of the FeCrMo binder phase induces significant microstructural changes both after sintering and after subsequent thermal treatment. Thus, the alloy with higher carbon content (that with metallic Mo) presents higher precipitation of Cr-rich M7C3 carbides at the (Ti1-x,Mox)yCz - metal interface and certain amount of retained austenite. In the alloy with lower carbon content (that with Mo2C), there is no retained austenite, and the precipitation of Cr-rich carbides is less abundant. By means of EDS-TEM analyses of the metallic matrix of TiC-Fe-Cr-Mo cermets after sintering, it was found to be alloyed with Cr and Mo. The contents of these elements are similar to those reported for hot work steels (i.e., AISI H11 or H13). However, these metallic matrices are very different as they do not contain Si, Mn or V. With the aim of studying the hardenability of these materials, thermal treatments have been carried out after sintering using a quenching dilatometer. Volumetric changes associated to phase transformations have been measured by austenitizing at 950 ºC for 20 min and subsequently cooling at different rates (from 100 ºC/s to 0.1 ºC/s). Carbon differences are observed to shift bainitic transformation, with its onset found at approximately 1 ºC/s. As expected, this transformation is shifted towards higher temperatures as the total carbon content of the alloy decreases. CCT diagrams built on the basis of dilatometric results confirm that bainitic transformation occurs at higher cooling rates than in standard hot work steels. Anyhow, the metallic matrices present in these TiC-Fe-Cr-Mo cermets are air-quenchable at approximately 1 ºC/s, inducing a hardness increase of 30 % with respect to that of as-sintered materials. Precipitation of M7C3 and M23C6 carbides is observed by means of SEM/TEM analyses and XRD measurements. These findings agree with thermodynamic calculations made by Thermocalc® software. Although it still unclear, preliminary results suggest that the precipitation of M23C6 carbides is related to the progression of the bainitic transformation
Exposición de ideas sobre proyectos en química a través de un formato de presentación creativo
No full textLa asignatura de Proyectos en Química, 4o curso
del grado de Química pretende formar al alumno en el análisis y la
comprensión de los aspectos fundamentales que recoge un proyecto
relacionado con la industria química. El objetivo global de este proyecto de
innovación docente es promover la exposición de ideas generales e innovadoras sobre proyectos relacionados con la industria química
mediante un formato creativo y dinámico de presentación: PechaKucha.
Este proyecto se fundamenta en el proyecto de innovación docente
concedido en el pasado curso 2012/2013, PID Ciencias 4/2012: "Nuevo
formato de exposición aplicado a proyectos en Química", que ha mostrado
una buena acogida por parte del alumnado y una valoración positiva por
parte del profesorado. En un sentido general, se pretende estimular la
capacidad creativa del alumno, tanto por la idea propuesta en sí, como por
el formato de exposición empleado, pues la creatividad puede ser el origen
del éxito del proyecto
Decreased expression of the NLRP6 inflammasome is associated with increased intestinal permeability and inflammation in obesity with type 2 diabetes
No full textBackground Obesity-associated dysfunctional intestinal permeability contributes to systemic chronic infammation leading
to the development of metabolic diseases. The infammasomes constitute essential components in the regulation of intestinal homeostasis. We aimed to determine the impact of the infammasomes in the regulation of gut barrier dysfunction and
metabolic infammation in the context of obesity and type 2 diabetes (T2D).
Methods Blood samples obtained from 80 volunteers (n=20 normal weight, n=21 OB without T2D, n=39 OB with T2D)
and a subgroup of jejunum samples were used in a case–control study. Circulating levels of intestinal damage markers and
expression levels of infammasomes as well as their main efectors (IL-1β and IL-18) and key infammation-related genes
were analyzed. The impact of infammation-related factors, diferent metabolites and Akkermansia muciniphila in the regulation of infammasomes and intestinal integrity genes was evaluated. The efect of blocking NLRP6 by using siRNA in
infammation was also studied.
Results Increased circulating levels (P<0.01) of the intestinal damage markers endotoxin, LBP, and zonulin in patients
with obesity decreased (P<0.05) after weight loss. Patients with obesity and T2D exhibited decreased (P<0.05) jejunum
gene expression levels of NLRP6 and its main efector IL18 together with increased (P<0.05) mRNA levels of infammatory markers. We further showed that while NLRP6 was primarily localized in goblet cells, NLRP3 was localized in the
intestinal epithelial cells. Additionally, decreased (P<0.05) mRNA levels of Nlrp1, Nlrp3 and Nlrp6 in the small intestinal
tract obtained from rats with diet-induced obesity were found. NLRP6 expression was regulated by taurine, parthenolide
and A. muciniphila in the human enterocyte cell line CCL-241. Finally, a signifcant decrease (P<0.01) in the expression
and release of MUC2 after the knockdown of NLRP6 was observed.
Conclusions The increased levels of intestinal damage markers together with the downregulation of NLRP6 and IL18 in the
jejunum in obesity-associated T2D suggest a defective infammasome sensing, driving to an impaired epithelial intestinal
barrier that may regulate the progression of multiple obesity-associated comorbidities
Elevated CO2 alleviates the exacerbation of evapotranspiration rates of grapevine (Vitis vinifera) under elevated temperature
Get PDFClimate change is increasing crop water consumption while reducing precipitations in most places where
grapevines are grown. This study aimed to quantify whole-plant water consumption of grapevines under climate
change factors to determine what are the biggest contributors to changes in evapotranspiration under climate
change conditions. Two experiments were carried out: i) Cabernet Sauvignon grafted onto 110 R grown in the
temperature gradient greenhouses (TGG) exposed to elevated CO2 (700 μmol mol− 1) and/or elevated temperature (+4 ◦C) and ii) Tempranillo vegetative cuttings grown in the controlled environment greenhouses (CEG)
exposed to ambient CO2 and standard temperatures (i.e CA24◦C) or elevated CO2 combined with elevated
temperature (i.e CE28◦C) under cyclic water deficit conditions. In the overall, the combination of elevated CO2
and elevated temperature did not increase pot evapotranspiration, and in the only case this happened, it was
mediated by a greater leaf area per plant. There was an interaction in which CO2 compensated for the increase in
evapotranspiration induced by elevated temperature. Plants under elevated CO2 and elevated temperature
(CETE) had lower stomatal conductance which resulted in similar transpiration rates to plants under ambient
CO2 and ambient temperature conditions (CATA) despites the 4 ◦C increase. Net assimilation was greater under
elevated CO2, and thus, instantaneous water use efficiency (WUE). Pot evapotranspiration was correlated to
parameters such as leaf area per plant, gas exchange transpiration rates, reference evapotranspiration and plant
available water content in the substrate. Pot lysimeters are a good compromise to study whole-plant water
consumption rates under controlled conditions. Climate change conditions will likely continue to threat the
sustainability of crops due to water shortages, however, our results point out that the interaction between
elevated temperature and CO2 should be considered. The sensitivity of plant responses to elevated CO2 could be
exploited as a key trait for the adaptation of crops to climate change
NetActivity enhances transcriptional signals by combining gene expression into robust gene set activity scores through interpretable autoencoders
No full textGrouping gene expression into gene set activity scores (GSAS) provides better biological insights than studying individual genes. However,
existing gene set projection methods cannot return representative, robust, and interpretable GSAS. We developed NetActivity, a machine learning
framework that generates GSAS based on a sparsely-connected autoencoder, where each neuron in the inner layer represents a gene set.
We proposed a three-tier training that yielded representative, robust, and interpretable GSAS. NetActivity model was trained with 1518 GO
biological processes terms and KEGG pathways and all GTEx samples. NetActivity generates GSAS robust to the initialization parameters and
representative of the original transcriptome, and assigned higher importance to more biologically relevant genes. Moreover, NetActivity returns
GSAS with a more consistent definition and higher interpretability than GSVA and hipathia, state-of-the-art gene set projection methods. Finally,
NetActivity enables combining bulk RNA-seq and microarray datasets in a meta-analysis of prostate cancer progression, highlighting gene sets
related to cell division, key for disease progression. When applied to metastatic prostate cancer, gene sets associated with cancer progression
were also altered due to drug resistance, while a classical enrichment analysis identified gene sets irrelevant to the phenotype. NetActivity is
publicly available in Bioconductor and GitHub
Cardiometabolic risk stratification using a novel obesity phenotyping system based on body adiposity and waist circumference
No full textBackground: The estimation of obesity-associated cardiometabolic risk does not usually take into account body
composition or the distribution of adiposity. The aim of the present study was to assess the clinical usefulness of a
novel obesity phenotyping system based on the combination of actual body fat percentage (BF%) and waist
circumference (WC) according to the cardiometabolic risk estimation.
Methods: A classification matrix combining BF% and WC as measures of both amount and distribution of
adiposity establishing nine body phenotypes (3 BF% x 3 WC) was developed. Individuals were grouped in five
different cardiometabolic risk phenotypes. We conducted a validation study in a large cohort of White subjects
from both genders representing a wide range of ages and adiposity (n = 12,754; 65 % females, aged 18–88
years).
Results: The five risk groups using the matrix combination of BF% and WC exhibited a robust linear distribution
regarding cardiometabolic risk, estimated by the Metabolic Syndrome Severity Score, showing a continuous
increase between groups with significant differences (P < 0.001) among them, as well as in other cardiometabolic risk factors. An additional 24 % of patients at very high risk was detected with the new classification system proposed (P < 0.001) as compared to an equivalent matrix using BMI and WC instead of BF% and
WC.
Conclusions: A more detailed phenotyping should be a priority in the diagnosis and management of patients with
obesity. Our classification system allows to gradually estimate the cardiometabolic risk according to BF% and
WC, thus representing a novel and useful tool for both research and clinical practice