Synthesis of 2-methyl- and 2-methylenecyclobutane amino acids

An efficient and easy formal [2+2] cycloaddition (Michael-Dieckmann-type reaction) on methyl 2-acetamidoacrylate with ketene diethyl acetal gave the cyclobutane core. Two kinds of 2-substituted cyclobutane amino acids have been obtained from this compound by means of stereocontrolled interconversion of functional groups: 1-amino-2-methylcyclobutane-1-carboxylic acids (2,4-methanovalines) and 1-amino-2-methylenecyclobutane-1-carboxylic acid. The latter amino acid can be regarded as a restricted -methyl-- vinylglycine. © 2005 Elsevier Ltd. All rights reserved

Implantación y análisis de un sistema de respuesta interactiva en el aula

En el curso académico 2011/12 se ha introducido como innovación educativa en la ETSI de Telecomunicación de la UPM un sistema de respuesta interactiva basado en mandos de radio frecuencia para el soporte a la participación de los alumnos en el aula. El presente documento pretende describir la experiencia de su implantación en tres asignaturas de diferente tipología. De acuerdo a los resultados obtenidos hasta el momento, los alumnos estacan la facilidad de uso del sistema y la mejora en cuanto a su participación en clase, estando interesados en su utilización en otras asignaturas. Por parte de los profesores, destaca que se dispone de información instantánea del proceso de aprendizaje individualizado del alumno, lo que permite incidir inmediatamente en aquellas cuestiones con peores resultados. Los principales inconvenientes se centran en su baja aportación a la asistencia a clase y a la retención y comprensión de conceptos

Vástagos cementados y no cementados en artroplastias totales de cadera por coxopatías mecánicas

En la controversia sobre la cementación o no del componente femoral se presenta el análisis clínico, radiológico y de supervivencia de los vástagos de una serie de 121 artoplastias totales de cadera (61 cementadas y 60 sin cementar). El estudio no evidencia diferencias significativas a los 5 años de seguimiento, aunque es destacable una mayor incidencia de dolor en el muslo entre los vástagos no cementados (35%) (p < 0,1) y una tasa de reabsorción ósea proximal más elevada (70%) que en los cementados (23%). Estos fenómenos son diseño dependientes. Un mayor número de cirugías de revisión por aflojamiento aséptico entre las prótesis cementadas nos hacen preferir la fijación sin cemento del componente femoral.We discuss the cemented or non-cement fixation of the femoral components in total hip arthroplasty on a serie of 121 femoral stem (61 cemented stem and 60 non-cemented stem). Survival analysis, clinical and radiographic data showed no significant differences between the two groups at 5 years follow-up. However the incidence of pain thigh phenomenon was higher for the non-cemented stem (35%) (p < 0.1). Stress schielding was evidently higher between the non-cemented implants (70%) too, as compared with cemented stem (23%). These findings are design-dependent. The cemented arthroplasties had a higher rate of revision procedures because of aseptic loosening (13%). In this way we prefer the non-cement fixation of the femoral implant

A course agnostic approach to predicting student success from VLE log data using recurrent neural networks

We describe a method of improving the accuracy of a learning analytics system through the application of a Recurrent Neural Network over all students in a University, regardless of course. Our target is to discover how well a student will do in a class given their interaction with a virtual learning environment. We show how this method performs well when we want to predict how well students will do, even if we do not have a model trained based on their specific course

Ongoing large randomized clinical trials on complex percutaneous coronary interventions:Intravascular imaging-guided trials

.tabletop{ vertical-align: top; } ABSTRACT Percutaneous coronary intervention of complex coronary artery disease remains challenging and is still associated with suboptimal cardiovascular outcomes. Over the years, different strategies and technologies have been developed to improve these results. Particularly, the development and evolution of intravascular imaging modalities to guide the procedure have improved lesion assessment and preparation, and stent optimization. However, whether these advantages are beneficial in this particular setting is still under discussion. In this article we intend to briefly summarize previous imaging-guided trials and give an outline on the ongoing large trials that are being conducted on imaging-guided interventions in complex coronary disease

Fracturas de húmero complicadas con lesión arterial

Presentamos una serie de 10 pacientes afectos de una fractura de húmero asociada a una lesión arterial, tratados entre Enero de 1990 y Octubre de 1993. Dentro de la serie distinguimos tres grupos, de acuerdo con la localización de la fractura (tercio proximal, diáfisis, región supracondílea). El análisis de los resultados sugiere que el peor pronóstico corresponde a las lesiones proximales y diafisarias por su etiología, daños asociados y menor posibilidad de circulación colateral de suplencia. El manejo de estas lesiones complejas exige un tratamiento quirúrgico interdisciplinario. Señalamos la utilidad de la fijación externa como método de osteosíntesis y el uso de un «shunt» provisional para perfundir el miembro durante la cirugía ósea. Se discute la indicación de arteriografía en los traumatismos agudos del miembro superior.A serie of 10 patients with a fracture of the humerus and associated arterial injury treated from January 1990 to October 1993 is reported. The serie was divided in 3 groups acording the proximal, mid shaft or supracondylar location of the fracture. Clinical results indicate a poor prognosis of proximal and mid shaft fractures related to their etiology, associated injuries and damage of the colateral vessels. The management of these complex injuries require an interdisciplinar approach. External fixation is an usefull stabilitation method for fractures associated with vascular damage. The utility of a temporary intraluminar vascular shunt to perfuse the limb at the bone surgery and preoperative arteriography are discussed

Post-transcriptional control in the regulation of polyhydroxyalkanoates synthesis

Funding Information: Funding: Work at ITQB NOVA was financially supported by the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie ID: 867437, and projects UIDB/04612/2020 and UIDP/04612/2020 (Molecular, Structural and Cellular Microbiology), funded by FEDER through COMPETE 2020—Programa Operacional Competitividade e Internacionalização (POCI) and by national funds through FCT—Fundação para a Ciência e a Tecnologia; Work at NOVA School of Science and Technology FCT I.P., was funded by national funds from FCT—Fundação para a Ciência e a Tecnologia, I.P., in the scope of the project UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences—UCIBIO and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy-i4HB. Funding Information: Work at ITQB NOVA was financially supported by the European Union?s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie ID: 867437, and projects UIDB/04612/2020 and UIDP/04612/2020 (Molecular, Structural and Cellular Microbiology), funded by FEDER through COMPETE 2020?Programa Operacional Competitividade e Internacionaliza??o (POCI) and by national funds through FCT?Funda??o para a Ci?ncia e a Tecnologia; Work at NOVA School of Science and Technology FCT I.P., was funded by national funds from FCT?Funda??o para a Ci?ncia e a Tecnologia, I.P., in the scope of the project UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences?UCIBIO and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy-i4HB. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.The large production of non-degradable petrol-based plastics has become a major global issue due to its environmental pollution. Biopolymers produced by microorganisms such as polyhy-droxyalkanoates (PHAs) are gaining potential as a sustainable alternative, but the high cost associated with their industrial production has been a limiting factor. Post-transcriptional regulation is a key step to control gene expression in changing environments and has been reported to play a major role in numerous cellular processes. However, limited reports are available concerning the regulation of PHA accumulation in bacteria, and many essential regulatory factors still need to be identified. Here, we review studies where the synthesis of PHA has been reported to be regulated at the post-transcriptional level, and we analyze the RNA-mediated networks involved. Finally, we discuss the forthcoming research on riboregulation, synthetic, and metabolic engineering which could lead to improved strategies for PHAs synthesis in industrial production, thereby reducing the costs currently associated with this procedure.publishersversionpublishe

Applications of 1H Nuclear Magnetic Resonance Spectroscopy in Clinical Microbiology

Proton nuclear magnetic resonance (1H NMR) is a spectroscopic technique usually used for structural determination of molecules. In recent years, this technique has been employed for easy and quick recognition of microorganisms, in antimicrobial susceptibility tests and even for the diagnosis of different infectious conditions. Though 1H NMR shows great potential for expanded applications in microbiological studies, to date applications of proton NMR to microbiological research are not totally standardized. In this chapter, we summarize the state of knowledge about 1H NMR and its current and potential applications in this field

Costos de la licencia de maternidad para apoyar la lactancia materna en Brasil, Ghana y México

Objective To develop a method to assess the cost of extending the duration of maternity leave for formally-employed women at the national level and apply it in Brazil, Ghana and Mexico. Methods We adapted a World Bank costing method into a five-step method to estimate the costs of extending the length of maternity leave mandates. Our method used the unit cost of maternity leave based on working women’s weekly wages; the number of additional weeks of maternity leave to be analysed for a given year; and the weighted population of women of reproductive and legal working age in a given country in that year. We weighted the population by the probability of having a baby that year among women in formal employment, according to individual characteristics. We applied nationally representative cross-sectional data from fertility, employment and population surveys to estimate the costs of maternity leave for mothers employed in the formal sector in Brazil, Ghana and Mexico for periods from 12 weeks up to 26 weeks, the WHO target for exclusive breastfeeding. Findings We estimated that 640 742 women in Brazil, 33 869 in Ghana and 288 655 in Mexico would require formal maternity leave annually. The median weekly cost of extending maternity leave for formally working women was purchasing power parity international dollars (PPP$) 195.07 per woman in Brazil, PPP$ 109.68 in Ghana and PPP$ 168.83 in Mexico. Conclusion Our costing method could facilitate evidence-based policy decisions across countries to improve maternity protection benefits and support breastfeeding