342 research outputs found

    Carbazole-based Diradicals for Dynamic Covalent Chemistry

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    Dynamic covalent chemistry (DCC) is focused on the creation of structural scaffolds based on chemical components that interact through strong but reversible bonds. In fact, dynamic covalent bonds receive lot of attention because of their unique feature to become reversible under mild conditions.1 conjugated diradical compounds has emerged as essential building blocks in DCC.2 In this work, we will review our most recent works on the formation of stimuli-responsive cyclophanes by self-assembly of carbazole-based diradicals. To this end, we use a combined experimental and theoretical approach that links vibrational spectroscopy with DFT calculations. In this sense, it is interesting to note that we have recently demonstrated the potential of a para-substituted carbazole with terminal dicyanomethylene (DCM) groups to act as building blocks in DCC.3 This quinoid carbazole monomer transforms to a macrocycle cyclophane upon soft external stimuli (temperature, pressure, light), showing strong chromic features. In addition, we have also recently explored how the different DCM substitution position affects the interesting chromoactive properties of carbazole compounds.4 Finally, we are currently exploring the effect of the elongation of the carbazole backbone on the formation of stimuli-responsive cyclophanes.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Multiresponsive chromic soft materials: formation of strongly coupled σ-dimers from IndoloCarbazole-based biradicaloids

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    Dynamic covalent chemistry is focused on the creation of structural scaffolds based on chemical components that interact through strong but reversible bonds. In fact, dynamic covalent bonds receive lot of attention because of their unique feature to become reversible under mild conditions.1 π-conjugated biradical compounds has emerged as essential building blocks in DCC (dynamic covalent chemistry).2 We have recently demonstrated the potential of a para-substituted carbazole with terminal dicyanomethylene groups to act as building blocks in DCC.3 In fact, this quinoid carbazole monomer transform to a macrocycle cyclophane upon soft external stimuli (temperature, pressure, light), showing strong chromic features. Here, we explore the effect of the elongation of the carbazole backbone on the formation of stimuli-responsive cyclophanes by self-assembly. To this end, we use a join experimental and theoretical approach that links vibrational spectroscopy (Raman and IR) with DFT calculationsUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Antenatal Fear of Childbirth as a Risk Factor for a Bad Childbirth Experience

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    Giving birth is one of the most impressive experiences in life. However, many pregnant women suffer from fear of childbirth (FOC) and experience labour in very different ways, depending on their personality, previous life experiences, pregnancy, and birth circumstances. The aim of this study was to analyse how fear of childbirth affects the childbirth experience and to assess the related consequences. For this, a descriptive cross-sectional study was carried out in a sample of 414 women between 1 July 2021 and 30 June 2022. The Birth Anticipation Scale (BAS) was used to measure fear of childbirth and the Childbirth Experience Questionnaire (CEQ-E) was applied to measure satisfaction with the childbirth experience. Fear of childbirth negatively and significantly predicted the childbirth experience. In addition, women who were more fearful of childbirth were found to have worse obstetric outcomes and a higher likelihood of having a caesarean delivery (p = 0.008 C. I 95%). Fear behaved as a risk factor for the birth experience, so the greater the fear, the higher the risk of having a worse birth experience (OR 1.1). Encouraging active listening and support strategies may increase pregnant women's confidence, thus decreasing their fear of the process and improving their childbirth experience

    Fitness vs Fatness as Determinants of Survival in Noninstitutionalized Older Adults: The EXERNET Multicenter Study

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    Background Physical fitness and body composition are important health indicators; nevertheless, their combined pattern interrelationships and their association with mortality are poorly investigated. Methods This longitudinal study is part of the Spanish EXERNET-Elder project. Person-months of follow-up were calculated from the interview date, performed between June 2008 and November 2009, until the date of death or censoring on March 2018 (whichever came first). In order to be included, participants had to fulfill the following criteria: (a) be older than 65 years, (b) live independently at home, (c) not suffer dementia and/or cancer, and (d) have a body mass index above 18.5. Body fat and weight were assessed by a bioelectrical impedance analyzer. Fitness was measured with the Senior Fitness and the one-leg static balance tests. The Spanish Death Index was consulted for the death’s identification. Cluster analysis was performed to identify Fat–Fit patterns and traditional cut-points and percentiles to create the Fat–Fit groups. Cox proportional hazards regression models were used to calculate the hazard ratios (HRs) of death in clustered Fat–Fit patterns and in traditional Fat–Fit groups. Results A total of 2299 older adults (76.8% of women) were included with a baseline mean age of 71.9 ± 5.2 years. A total of 196 deaths (8.7% of the sample) were identified during the 8 years of follow-up. Four clustered Fat–Fit patterns (Low fat–Fit, Medium fat–Fit, High fat–Unfit, and Low fat–Unfit) and 9 traditional Fat–Fit groups emerged. Using the Low fat–Fit pattern as the reference, significantly increased mortality was noted in High fat–Unfit (HR: 1.68, CI: 1.06–2.66) and Low fat–Unfit (HR: 2.01, CI: 1.28–3.16) groups. All the traditional Fit groups showed lower mortality risk when compared to the reference group (obese–unfit group). Conclusion Physical fitness is a determinant factor in terms of survival in community-dwelling older adults, independently of adiposity levels

    Associations between Daily Movement Distribution, Bone Structure, Falls, and Fractures in Older Adults: A Compositional Data Analysis Study

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    With aging, bone density is reduced, increasing the risk of suffering osteoporosis and fractures. Increasing physical activity (PA) may have preventive effects. However, until now, no studies have considered movement behaviors with compositional data or its association to bone mass and structure measured by peripheral computed tomography (pQCT). Thus, the aim of our study was to investigate these associations and to describe movement behavior distribution in older adults with previous falls and fractures and other related risk parameters, taking into account many nutritional and metabolic confounders. In the current study, 70 participants above 65 years old (51 females) from the city of Zaragoza were evaluated for the EXERNET-Elder 3.0 project. Bone mass and structure were assessed with pQCT, and PA patterns were objectively measured by accelerometry. Prevalence of fear of falling, risk of falling, and history of falls and fractures were asked through the questionnaire. Analyses were performed using a compositional data approach. Whole-movement distribution patterns were associated with cortical thickness. In regard to other movement behaviors, moderate-to-vigorous PA (MVPA) showed positive association with cortical thickness and total true bone mineral density (BMD) at 38% (all p < 0.05). In addition, less light PA (LPA) and MVPA were observed in those participants with previous fractures and fear of falling, whereas those at risk suggest that different exercise interventions should be designed in these populations in order to improve bone and prevent the risk of osteoporosis and subsequent fractures of falling and those with previous falls showed higher levels of PA. Our results showed positive associations between higher levels of MVPA and volumetric bone. The different movement patterns observed in the groups with a history of having suffered falls or fractures and other risk outcome

    Type II Supernova Spectral Diversity. I. Observations, Sample Characterization, and Spectral Line Evolution

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    We present 888 visual-wavelength spectra of 122 nearby type II supernovae (SNe II) obtained between 1986 and 2009, and ranging between 3 and 363 days post-explosion. In this first paper, we outline our observations and data reduction techniques, together with a characterization based on the spectral diversity of SNe II. A statistical analysis of the spectral matching technique is discussed as an alternative to nondetection constraints for estimating SN explosion epochs. The time evolution of spectral lines is presented and analyzed in terms of how this differs for SNe of different photometric, spectral, and environmental properties: velocities, pseudo-equivalent widths, decline rates, magnitudes, time durations, and environment metallicity. Our sample displays a large range in ejecta expansion velocities, from ∼9600 to ∼1500 km s-1 at 50 days post-explosion with a median Hα value of 7300 km s-1. This is most likely explained through differing explosion energies. Significant diversity is also observed in the absolute strength of spectral lines, characterized through their pseudo-equivalent widths. This implies significant diversity in both temperature evolution (linked to progenitor radius) and progenitor metallicity between different SNe II. Around 60% of our sample shows an extra absorption component on the blue side of the Hα P-Cygni profile ("Cachito" feature) between 7 and 120 days since explosion. Studying the nature of Cachito, we conclude that these features at early times (before ∼35 days) are associated with Si ii λ6355, while past the middle of the plateau phase they are related to high velocity (HV) features of hydrogen lines.Facultad de Ciencias Astronómicas y GeofísicasInstituto de Astrofísica de La Plat

    Contributions of mean and shape of blood pressure distribution to worldwide trends and variations in raised blood pressure: A pooled analysis of 1018 population-based measurement studies with 88.6 million participants

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    © The Author(s) 2018. Background: Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure. Methods: We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP) and prevalence of raised blood pressure by sex and 10-year age group from 20-29 years to 70-79 years in each study, taking into account complex survey design and survey sample weights, where relevant. We used a linear mixed effect model to quantify the association between (probittransformed) prevalence of raised blood pressure and age-group- and sex-specific mean blood pressure. We calculated the contributions of change in mean SBP and DBP, and of change in the prevalence-mean association, to the change in prevalence of raised blood pressure. Results: In 2005-16, at the same level of population mean SBP and DBP, men and women in South Asia and in Central Asia, the Middle East and North Africa would have the highest prevalence of raised blood pressure, and men and women in the highincome Asia Pacific and high-income Western regions would have the lowest. In most region-sex-age groups where the prevalence of raised blood pressure declined, one half or more of the decline was due to the decline in mean blood pressure. Where prevalence of raised blood pressure has increased, the change was entirely driven by increasing mean blood pressure, offset partly by the change in the prevalence-mean association. Conclusions: Change in mean blood pressure is the main driver of the worldwide change in the prevalence of raised blood pressure, but change in the high-blood-pressure tail of the distribution has also contributed to the change in prevalence, especially in older age groups

    Ahora / Ara

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    La cinquena edició del microrelatari per l’eradicació de la violència contra les dones de l’Institut Universitari d’Estudis Feministes i de Gènere «Purificación Escribano» de la Universitat Jaume I vol ser una declaració d’esperança. Aquest és el moment en el qual les dones (i els homes) hem de fer un pas endavant i eliminar la violència sistèmica contra les dones. Ara és el moment de denunciar el masclisme i els micromasclismes començant a construir una societat més igualitària. Cadascun dels relats del llibre és una denúncia i una declaració que ens encamina cap a un món millor

    Precariedad, exclusión social y diversidad funcional (discapacidad): lógicas y efectos subjetivos del sufrimiento social contemporáneo (II). Innovación docente en Filosofía

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    El PIMCD "Precariedad, exclusión social y diversidad funcional (discapacidad): lógicas y efectos subjetivos del sufrimiento social contemporáneo (II). Innovación docente en Filosofía" se ocupa de conceptos generalmente eludidos por la tradición teórica (contando como núcleos aglutinantes los de la precariedad laboral, la exclusión social y diversidad funcional o discapacidad), cuyo análisis propicia nuevas prácticas en la enseñanza universitaria de filosofía, adoptando como meta principal el aprendizaje centrado en el estudiantado, el diseño de nuevas herramientas de enseñanza y el fomento de una universidad inclusiva. El proyecto cuenta con 26 docentes de la UCM y otros 28 docentes de otras 17 universidades españolas (UV, UNED, UGR, UNIZAR, UAH, UC3M, UCA, UNIOVI, ULL, EHU/UPV, UA, UAM, Deusto, IFS/CSIC, UCJC, URJC y Univ. Pontificia de Comillas), que permitirán dotar a las actividades programadas de un alcance idóneo para consolidar la adquisición de competencias argumentativas y dialécticas por parte de lxs estudiantes implicados en el marco de los seminarios previstos. Se integrarán en el PIMCD, aparte de PDI, al menos 26 estudiantes de máster y doctorado de la Facultad de Filosofía, a lxs que acompañarán durante el desarrollo del PIMCD 4 Alumni de la Facultad de Filosofía de la UCM, actualmente investigadores post-doc y profesorxs de IES, cuya experiencia será beneficiosa para su introducción en la investigación. Asimismo, el equipo cuenta con el apoyo de varixs profesorxs asociadxs, que en algunos casos son también profesores de IES. Varixs docentes externos a la UCM participantes en el PIMCD poseen una dilatada experiencia en la coordinación de proyectos de innovación de otras universidades, lo que redundará en beneficio de las actividades a desarrollar. La coordinadora y otrxs miembros del PIMCD pertenecen a la Red de Innovación Docente en Filosofia (RIEF), puesta en marcha desde la Universitat de València (http://rief.blogs.uv.es/encuentros-de-la-rief/), a la que mantendremos informada de las actividades realizadas en el proyecto. Asimismo, lxs 6 miembros del PAS permitirán difundir debidamente las actividades realizadas en el PIMCD entre lxs estudiantes Erasmus IN del curso 2019/20 en la Facultad de Filosofía, de la misma manera que orientar en las tareas de maquetación y edición que puedan ser necesarias de cara a la publicación de lxs resultados del PIMCD y en las tareas de pesquisa bibliográfica necesarias para el desarrollo de los objetivos propuestos. Han manifestado su interés en los resultados derivados del PIMCD editoriales especializadas en la difusión de investigaciones predoctorales como Ápeiron y CTK E-Books
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