66 research outputs found

    Small Cofactors May Assist Protein Emergence from RNA World: Clues from RNA-Protein Complexes

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    It is now widely accepted that at an early stage in the evolution of life an RNA world arose, in which RNAs both served as the genetic material and catalyzed diverse biochemical reactions. Then, proteins have gradually replaced RNAs because of their superior catalytic properties in catalysis over time. Therefore, it is important to investigate how primitive functional proteins emerged from RNA world, which can shed light on the evolutionary pathway of life from RNA world to the modern world. In this work, we proposed that the emergence of most primitive functional proteins are assisted by the early primitive nucleotide cofactors, while only a minority are induced directly by RNAs based on the analysis of RNA-protein complexes. Furthermore, the present findings have significant implication for exploring the composition of primitive RNA, i.e., adenine base as principal building blocks

    Sobolev spaces on non-Lipschitz subsets of Rn with application to boundary integral equations on fractal screens

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    We study properties of the classical fractional Sobolev spaces on non-Lipschitz subsets of Rn. We investigate the extent to which the properties of these spaces, and the relations between them, that hold in the well-studied case of a Lipschitz open set, generalise to non-Lipschitz cases. Our motivation is to develop the functional analytic framework in which to formulate and analyse integral equations on non-Lipschitz sets. In particular we consider an application to boundary integral equations for wave scattering by planar screens that are non-Lipschitz, including cases where the screen is fractal or has fractal boundary

    Mitochondria and the central nervous system: searching for a pathophysiological basis of psychiatric disorders

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    Exotic fish in exotic plantations: a multi-scale approach to understand amphibian occurrence in the mediterranean region

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    Globally, amphibian populations are threatened by a diverse range of factors including habitat destruction and alteration. Forestry practices have been linked with low diversity and abundance of amphibians. The effect of exotic Eucalyptus spp. plantations on amphibian communities has been studied in a number of biodiversity hotspots, but little is known of its impact in the Mediterranean region. Here, we identify the environmental factors influencing the presence of six species of amphibians (the Caudata Pleurodeles waltl, Salamandra salamandra, Lissotriton boscai, Triturus marmoratus and the anurans Pelobates cultripes and Hyla arborea/meridionalis) occupying 88 ponds. The study was conducted in a Mediterranean landscape dominated by eucalypt plantations alternated with traditional use (agricultural, montados and native forest) at three different scales: local (pond), intermediate (400 metres radius buffer) and broad (1000 metres radius buffer). Using the Akaike Information Criterion for small samples (AICc), we selected the top-ranked models for estimating the probability of occurrence of each species at each spatial scale separately and across all three spatial scales, using a combination of covariates from the different magnitudes. Models with a combination of covariates at the different spatial scales had a stronger support than those at individual scales. The presence of predatory fish in a pond had a strong effect on Caudata presence. Permanent ponds were selected by Hyla arborea/meridionalis over temporary ponds. Species occurrence was not increased by a higher density of streams, but the density of ponds impacted negatively on Lissotriton boscai. The proximity of ponds occupied by their conspecifics had a positive effect on the occurrence of Lissotriton boscai and Pleurodeles waltl. Eucalypt plantations had a negative effect on the occurrence of the newt Lissotriton boscai and anurans Hyla arborea/meridionalis, but had a positive effect on the presence of Salamandra salamandra, while no effect on any of the other species was detected. In conclusion, eucalypts had limited effects on the amphibian community at the intermediate and broad scales, but predatory fish had a major impact when considering all the scales combined. The over-riding importance of introduced fish as a negative impact suggests that forest managers should prevent new fish introductions and eradicate fish from already-occupied ponds whenever possible

    Global burden of cardiovascular diseases and risk factors, 1990–2019: update from the GBD 2019 study

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    Cardiovascular diseases (CVDs), principally ischemic heart disease (IHD) and stroke, are the leading cause of global mortality and a major contributor to disability. This paper reviews the magnitude of total CVD burden, including 13 underlying causes of cardiovascular death and 9 related risk factors, using estimates from the Global Burden of Disease (GBD) Study 2019. GBD, an ongoing multinational collaboration to provide comparable and consistent estimates of population health over time, used all available population-level data sources on incidence, prevalence, case fatality, mortality, and health risks to produce estimates for 204 countries and territories from 1990 to 2019. Prevalent cases of total CVD nearly doubled from 271 million (95% uncertainty interval [UI]: 257 to 285 million) in 1990 to 523 million (95% UI: 497 to 550 million) in 2019, and the number of CVD deaths steadily increased from 12.1 million (95% UI:11.4 to 12.6 million) in 1990, reaching 18.6 million (95% UI: 17.1 to 19.7 million) in 2019. The global trends for disability-adjusted life years (DALYs) and years of life lost also increased significantly, and years lived with disability doubled from 17.7 million (95% UI: 12.9 to 22.5 million) to 34.4 million (95% UI:24.9 to 43.6 million) over that period. The total number of DALYs due to IHD has risen steadily since 1990, reaching 182 million (95% UI: 170 to 194 million) DALYs, 9.14 million (95% UI: 8.40 to 9.74 million) deaths in the year 2019, and 197 million (95% UI: 178 to 220 million) prevalent cases of IHD in 2019. The total number of DALYs due to stroke has risen steadily since 1990, reaching 143 million (95% UI: 133 to 153 million) DALYs, 6.55 million (95% UI: 6.00 to 7.02 million) deaths in the year 2019, and 101 million (95% UI: 93.2 to 111 million) prevalent cases of stroke in 2019. Cardiovascular diseases remain the leading cause of disease burden in the world. CVD burden continues its decades-long rise for almost all countries outside high-income countries, and alarmingly, the age-standardized rate of CVD has begun to rise in some locations where it was previously declining in high-income countries. There is an urgent need to focus on implementing existing cost-effective policies and interventions if the world is to meet the targets for Sustainable Development Goal 3 and achieve a 30% reduction in premature mortality due to noncommunicable diseases

    Safety out of control: dopamine and defence

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    Vivendo no método canguru a tríade mãe-filho-família Viviendo en el método canguru la tríade madre-hijo-familia Living the mother-child-family triad in the kangaroo method

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    Este estudo tem como foco a vivência da família no método canguru (MC), com os objetivos de compreender o funcionamento da dinâmica familiar e apreender as transformações familiares pela permanência no método. Utilizou-se como Referencial Teórico o Interacionismo Simbólico e o Referencial Metodológico a Grounded Teory. Dos dados emergiram os fenômenos: tendo evolução e desfecho não esperados na gestação, fase em que os pais experienciam a evolução de uma gravidez e sofrem diante da sua interrupção prematura; deparando com a prematuridade do filho, momento em que os pais entram no mundo da prematuridade, constatando a necessidade de agir pela sua sobrevivência; e vivendo a decisão e a experiência junto do filho, período que revela a possibilidade, ou não, de permanecer no MC no hospital. A partir desses fenômenos foi possível chegar à categoria central pesando riscos e benefícios entre estar com o filho no canguru ou com a família.<br>Este estudio tiene como tema principal la vivencia de la familia en el Método Madre Canguro (MC), con objeto de comprender el funcionamiento de la dinámica familiar y aprehender las transformaciones familiares por la permanencia en el método. Se utilizó como Referencial Teórico el Interaccionismo Simbólico y como Referencial Metodológico, la Teoría Fundamentada en los Datos. De los datos surgieron los fenómenos: evolución y desenlace no esperados del embarazo, fase en la que los padres vivencian el embarazo y sufren por la gestación interrumpida; deparándose con la prematuridad del hijo, momento en el que los padres entran en el mundo de los nacimientos prematuros, constatando la necesidad de actuar por la sobrevida de su hijo; y viviendo la decisión y la experiencia delante del hijo, período que revela la posibilidad o no de permanecer en el MC en el hospital. A partir de estos fenómenos fue posible llegar a la categoría central: pesando riesgos y beneficios entre quedarse con el hijo en el método canguro o con la familia.<br>This study focuses on the experience of families in the Kangaroo Mother Method (KM) and aims to understand the functioning of the family dynamics and to apprehend the family transformations as a result of their experience in the method. The study used Symbolic Interactionism as a theoretical and Grounded Theory as a methodological reference framework. Data revealed the following phenomena: having an unexpected evolution and outcome of pregnancy, which is a phase in which the parents go through a pregnancy and suffer due to its premature interruption; coping with the prematurity of the child, in which the parents get into the world of prematurity and face the need to act for the child's survival; and living with the decision and the experience together with the child, which reveals the possibility of staying in hospital in the KM or not. These phenomena led to the central category: weighing the risks and benefits between staying with the child in the kangaroo method or with the family
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