Síntesi i estudi de ciclopèptids antibiòtics

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2018, Tutor: Francesc Rabanal AngladaThere is currently an important clinical worldwide challenge around the infections produced by multidrug-resistant bacteria. The discovery of effective antibiotics has diminished a lot in recent years, evidencing a great threat and an urgent need of new and safer antibiotics with broader spectrum to fight against these bacteria. A new field of study consists in reconsidering polymyxin, a cyclopeptide that presents excellent antimicrobial activity against Gram-negative bacteria. However, its use has been reduced over the years due to their neuro and nephrotoxicity, so that they are currently used only as a last resort antibiotic. As a consequence, one of the research areas consists in the synthesis of polymyxin analogs with the aim of improving its biological activity and reducing its toxicity. Regarding this work, three polymyxin analogs are firstly synthesized by solid phase peptide synthesis using Fmoc/tBu orthogonal protection strategy. Secondly, cyclization is carried out by the oxidation between two cysteine residues and finally, the analogs obtained are characterized by using RP-HPLC and ESI mass spectrometry. Moderately good yields and high purity are obtained for the analogs synthetized. Subsequently, the microbiological activity of the analogs is evaluated by determining their minimum inhibitory concentration (MIC) and, later, their hemolytic activity is studied as a toxicity tes

The perils of thresholding

The thresholding of time series of activity or intensity is frequently used to define and differentiate events. This is either implicit, for example due to resolution limits, or explicit, in order to filter certain small scale physics from the supposed true asymptotic events. Thresholding the birth-death process, however, introduces a scaling region into the event size distribution, which is characterised by an exponent that is unrelated to the actual asymptote and is rather an artefact of thresholding. As a result, numerical fits of simulation data produce a range of exponents, with the true asymptote visible only in the tail of the distribution. This tail is increasingly difficult to sample as the threshold is increased. In the present case, the exponents and the spurious nature of the scaling region can be determined analytically, thus demonstrating the way in which thresholding conceals the true asymptote. The analysis also suggests a procedure for detecting the influence of the threshold by means of a data collapse involving the threshold-imposed scale.Comment: 16 pages, 10 figure

Can the use of an auditory feedback device improve the gait pattern of paediatric patients with hemiparesis?

Postprint (published version

Did policies to abate atmospheric emissions from traffic have a positive effect in London?

AbstractA large number of policy initiatives are being taken at the European level, across the United Kingdom and in London to improve air quality and reduce population exposure to harmful pollutants from traffic emissions. Trends in roadside increments of nitrogen oxides (NOX), nitrogen dioxide (NO2), particulate matter (PM), black carbon (CBLK) and carbon dioxide (CO2) were examined at 65 London monitoring sites for two periods of time: 2005–2009 and 2010–2014. Between 2005 and 2009 there was an overall increase in NO2 reflecting the growing evidence of real world emissions from diesel vehicles. Conversely, NO2 decreased by 10%·year−1 from 2010 onwards along with PM2.5 (−28%·year−1) and black carbon (−11%·year−1). Downwards trends in air pollutants were not fully explained by changes in traffic counts therefore traffic exhaust emission abatement policies were proved to be successful in some locations. PM10 concentrations showed no significant overall change suggesting an increase in coarse particles which offset the decrease in tailpipe emissions; this was especially the case on roads in outer London where an increase in the number of Heavy Good Vehicles (HGVs) was seen. The majority of roads with increasing NOX experienced an increase in buses and coaches. Changes in CO2 from 2010 onwards did not match the downward predictions from reduced traffic flows and improved fleet efficiency. CO2 increased along with increasing HGVs and buses. Polices to manage air pollution provided differential benefits across London's road network. To investigate this, k-means clustering technique was applied to group roads which behaved similarly in terms of trends to evaluate the effectiveness of policies to mitigate traffic emissions. This is the first time that London's roadside monitoring sites have been considered as a population rather than summarized as a mean behaviour only, allowing greater insight into the differential changes in air pollution abatement policies

How Soviet communism changed the family

Communist ideology in the Soviet Union initially sought to weaken the family and strengthen the role of the state. But did it achieve this aim? Drawing on new research, Joan Costa-Font and Anna Nicińska find that in contrast to expectations, exposure to communism appears to have strengthened preferences for family support for both children and parents

Use of water-based carbonyl-functional polymers on a cross-linker-free highperformance leather finish

The present paper aims to study a new high-performance coating formulation while avoiding the use of cross-linkers. By using acrylic polymers with carbonyl functional groups, the negative environmental effects of the finishing process can be minimized. These new polymers can give very good physical properties without losing the inherent properties of flexibility and elasticity needed in upholstery leatherPostprint (published version

Ús de minicasos a les classes expositives de psicologia

L’assoliment de l’Espai Europeu d’Educació Superior implica nous rols per a professors i alumnes i la introducció de noves metodologies docents. En aquest article es presenta una experiència d’innovació en la docència de la Psicologia consistent en la incorporació de minicasos a les classes expositives de l’assignatura troncal i anual “Avaluació Psicològica” de segon curs de la llicenciatura de Psicologia. S’exposa el procediment i s’analitza l’opinió dels estudiants respecte a la utilitats dels minicasos per incrementar l’atenció, l’interès i la comprensió de l’assignaturaEl logro del Espacio Europeo de Educación Superior implica nuevos roles para los profesores y alumnos, y la introducción de nuevas metodologías docentes. En el presente artículo se presenta una experiencia de innovación en la docencia de la Psicología consistente en la incorporación de minicasos en las clases expositivas de la asignatura troncal y anual “Evaluación Psicológica” de segundo curso de la licenciatura de Psicología. Se expone el procedimiento y se analiza la opinión de los estudiantes respecto a la utilización de los minicasos para incrementar la atención, el interés y la comprensión de la asignaturaThe achievement of the European Higher Education Area goals requires new roles of the professors and students, as well as the introduction of new educational methodologies. The aim of this article is to present an innovative approach to teaching psychology which consists of the application of minicases on the core subject of “Psychological Assessment”. The procedure and the student’s opinion about the utility of minicases to increase attention, interest and comprehension are discusse

Evaluation of live growing pigs of different genotypes and sexes using computed tomography

Conocer la composición corporal en animales vivos y la deposición de los diferentes tejidos durante su crecimiento es de vital importancia para, entre otras cosas, caracterizar el efecto de una genética, la condición sexual, el manejo e incluso analizar la eficiencia alimentaria y adecuar la dieta a cada estadio de crecimiento, ya que la composición en tejido graso y muscular del cuerpo de los animal está influenciada tanto por factores intrínsecos como extrínsecos. La aplicación de la tomografía computerizada (CT) en animales vivos permite analizar, de manera no invasiva, la evolución de la composición corporal de un mismo animal a lo largo del período de crecimiento. Esto permite modelizar el crecimiento y desarrollo de los diferentes tejidos del cuerpo sin necesidad alguna de sacrificar el animal. Esta tesis propone conocer la evolución de la composición corporal de cerdos de distintas genéticas (experimento 1) o sexos (experimento 2). El experimento 1 estaba formado por 90 animales de tres genéticas distintas (todas ellas comerciales y altamente utilizadas en el sector), y el experimento 2 estaba formado por 92 animales de cuatro condiciones sexuales distintas (hembras (FE), machos enteros (EM), machos castrados quirúrgicamente (CM) y machos inmunocastrados (IM)). Los animales se evaluaron con el CT a 30, 70, 100 i 120 kg de peso objetivo. Una submuestra de animales de cada genética y sexo (n=5/genética y n=4/sexo) se sacrificaron a los diferentes pesos objetivo y se disecaron total o parcialmente. El resto de animales (animales de seguimiento), se evaluaron con el CT a cada peso objetivo y, al llegar a 120 kg, se sacrificaron. A partir de los animales sacrificados y disecados, se obtuvieron ecuaciones de predicción, de la composición corporal y de las diferentes piezas, que se usaron en el resto de animales de seguimiento. Las predicciones se hicieron para cada genética independientemente (Chapter 4) o bien generalizadas para todas las genéticas y sexos (Chapter 6). Ambas ecuaciones fueron adecuadas para la predicción de la composición corporal (Chapter 8). En este sentido, presentar las predicciones individuales según la genética reduce el error (RMSE entre 0.011 y 0.886). No obstante, la ecuacion global permite generalizar las predicciones para un mayor número de animales, así pues, es preferible usarla cuando la población está mezclada o cuando el parámetro estimado no requiere un alto valor de precisión. Cuando esta precisión se requiere, como es el caso de compañías genéticas, es preferible utilizar las ecuaciones individuales, específicamente desarrolladas para cada genética. Los resultados muestran que los tejidos crecen de manera diferente según la genética s y el sexo (Chapter 5 y 7). El tejido que mostró el mayor coeficiente alométrico fue la grasa, indicando el índice de deposición más rápido de este tejido. De entre las distintas genéticas, LA fue quien mostró la deposición de grasa más rápida (Chapter 5), mientras que respecto a los sexos, los CM e IM fueron los que tuvieron un índice de deposición de grasa más elevado y más lento en los EM y FE (Chapter 7). El comportamiento de la deposición de magro fue inverso al de la grasa. Añadir que, los IM y CM tuvieron un comportamiento muy similar respecto a la velocidad de deposición de grasa y magro, a pesar que los IM se comportaron como los EM hasta que recibieron la segunda dosis de la vacuna de immunocastración. Finalmente, en las condiciones de realización de este trabajo se puede concluir que el CT puede ser muy útil para la industria cárnica, porque los parámetros de calidad y composición de la canal se pueden conocer a pesos muy tempranos. Como resultado, el uso de esta información puede aportar beneficios económicos para todos los integrantes de la cadena alimenticia.Knowledge of the composition of animal bodies and animal tissue growth is very important for the characterization of the effect of a genotype, the sexual condition, the management or to analyze the feed efficiency and adjust the diet to growth states, because fat and lean composition are dependent on intrinsic and extrinsic factors. The application of computed tomography (CT) to living animals allows analyzing non-invasively the evolution of the body composition of a single animal through its growing period. Subsequently, growth and development of the different body tissues can be modeled, without the necessity to slaughter the animal. The PhD Thesis at hand investigates the evolution of the composition of pig bodies from different genetic types (experiment 1) and sexual conditions (experiment 2). Experiment 1 was performed on 90 pigs of three genetic types (all of them were commercial and very used in the swine industry), while experiment 2 was performed on 92 animals with four different sexual conditions (females, entire males, castrated males and immunocastrated males). The animals were scanned by CT at 30, 70, 100 and 120 kg live weigh. One subsample for each genetic type and sexual condition (n=5/genetic type and n=4/sexual condition) were slaughtered at the different target weights and were fully or partially dissected. The rest of the animals (animals of the study) were evaluated with the CT at each target weight and, once they reached 120 kg, they were slaughtered. Knowledge gained from slaughtered and dissected animals was used to formulate prediction equations for body and pieces composition. They were then applied to the animals of the study. Predictions were performed independently for each genetic type (Chapter 4) or generalized for all the genetic types and sexual conditions of this work (Chapter 6). Both equations produce good results for the prediction of body composition (Chapter 8). Presenting the individual predictions depending on the genetic type reduces the error (RMSE between 0.011 and 0.886). However, the global equation allows generalizing the predictions for a bigger number of animals, thus, it has preference if the population is mixed or if high level of accuracy is not required. If high accuracy is needed, for instance for genetic companies, individual equations specifically developed for each genetic type are prefered. Results show that tissues grow different depending on the genetic type and sexual condition (Chapter 5 and 7). Tissue that shows the highest allometric coefficient was the fat, corresponding to the fastest deposition. From the different genotypes, LA was the one that shows the fastest deposition of fat (Chapter 5). With respect to the sexual condition, CM and IM exert the highest deposition value for the fat, with EM and FE showing the lowest (Chapter 7). Lean tissue behaves in the opposite way as fat. The IM and CM had a very similar behavior with respect to the deposition speed of fat and lean, even IM behave as EM until the study animals received the second dose of the immunocastration vaccine. In conclusion, CT can be very useful for the meat industry due to its ability to predict quality parameters, as well as carcass composition, at early growth stage. This technique can thus bring economic benefits for all the livestock and food chain industry

The institutional origins of vaccines distrust: evidence from former-Soviet countries

How is vaccines scepticism related to the exposure to Soviet communism? Using individual level evidence on vaccine trust with regards to its efficiency and safety in 122 countries that differ in their exposure to communism, we document that past exposure to Soviet communism is associated with lower trust in vaccination. We show that exposure to socio-political regimes can negatively affect trust in vaccines, which is explained by weak trust in both government and medical advice from doctors as well as in people from the neighbourhood. These results suggest that roots of vaccine scepticism lie in a wider distrust in public and state institutions resulting from the exposure to Soviet communism