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791.
Carole Keppler Timm Rosburg Patrick Lemoine Marlon Pflüger Niklaus Gyr Ralph Mager 《Applied psychophysiology and biofeedback》2016,41(4):363-373
Functional somatic syndromes are mostly associated with pain and emotional distress. As one marker for the autonomic stress response, the distal skin temperature decreases during psychological stress. In patients with functional somatic syndromes, the distal skin temperature under baseline conditions (without stress induction) is usually lower than in healthy subjects, which could be due to the sustained presence of pain-related stress in such patients. The aim of our study was to investigate whether patients with functional somatic syndromes show altered skin temperatures also under everyday life conditions. 14 patients with functional somatic syndromes and 14 matched healthy control subjects were investigated under ambulatory conditions over six consecutive days. During this time, distal and proximal skin temperatures were continuously recorded and sleep-wake cycles were monitored by actimetry and sleep-wake diaries. Unexpectedly, the patients showed higher distal skin temperatures than control subjects in the afternoon. The objective temperature data did not match the patients’ subjective experience: ratings of thermal comfort did not vary between the two groups. Moreover, similar levels of daytime activity were recorded in the two samples, even though patients reported more tiredness and more body tension than controls. We interpret the observed dissociation between objective skin temperature measurements and subjective ratings of the bodily thermal comfort as support for the notion of an alexisomia account (reduced bodily awareness) for functional somatic syndromes. Moreover, findings indicate that subjective complaints of tiredness and tension do not necessarily result in physical avoidance behaviour. 相似文献
792.
Semicontinuous system for the production of recombinant mCherry protein in Chlamydomonas reinhardtii
Cesar Andres Diaz Arias Marcelo Chuei Matsudo Livia Seno Ferreira-Camargo João Vitor Dutra Molino Stephen Patrick Mayfield João Carlos Monteiro de Carvalho 《Biotechnology progress》2021,37(2):e3101
Biotechnology advances have allowed bacteria, yeasts, plants, mammalian and insect cells to function as heterologous protein expression systems. Recently, microalgae have gained attention as an innovative platform for recombinant protein production, due to low culture media cost, compared to traditional systems, as well as the fact that microalgae such as Chlamydomonas reinhardtii are considered safe (GRAS) by the Food and Drug Administration (FDA). Previous studies showed that recombinant protein production in traditional platforms by semicontinuous process increased biomass and bio product productivity, when compared to batch process. As there is a lack of studies on semicontinuous process for recombinant protein production in microalgae, the production of recombinant mCherry fluorescent protein was evaluated by semicontinuous cultivation of Chlamydomonas reinhardtii in bubble column photobioreactor. This semicontinuous cultivation process was evaluated in the following conditions: 20%, 40%, and 60% culture portion withdrawal. The highest culture withdrawal percentage (60%) provided the best results, as an up to 161% increase in mCherry productivity (454.5 RFU h−1 – Relative Fluorescence Unit h−1), in comparison to batch cultivation (174.0 RFU h−1) of the same strain. All cultivations were carried out for 13 days, at pH 7, temperature 25°C and, by semicontinuous process, two culture withdrawals were taken during the cultivations. Throughout the production cycles, it was possible to obtain biomass concentration up to 1.36 g L−1. 相似文献
793.
Becoming a psychiatrist in Europe: the title is recognized across the European Union,but what are the differences in training,salary and working hours?
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794.
Ian R. McFadden Agnieszka Sendek Morgane Brosse Peter M. Bach Marco Baity-Jesi Janine Bolliger Kurt Bollmann Eckehard G. Brockerhoff Giulia Donati Friederike Gebert Shyamolina Ghosh Hsi-Cheng Ho Imran Khaliq J. Jelle Lever Ivana Logar Helen Moor Daniel Odermatt Loïc Pellissier Luiz Jardim de Queiroz Christian Rixen Nele Schuwirth J. Ryan Shipley Cornelia W. Twining Yann Vitasse Christoph Vorburger Mark K. L. Wong Niklaus E. Zimmermann Ole Seehausen Martin M. Gossner Blake Matthews Catherine H. Graham Florian Altermatt Anita Narwani 《Ecology letters》2023,26(2):203-218
Human impacts such as habitat loss, climate change and biological invasions are radically altering biodiversity, with greater effects projected into the future. Evidence suggests human impacts may differ substantially between terrestrial and freshwater ecosystems, but the reasons for these differences are poorly understood. We propose an integrative approach to explain these differences by linking impacts to four fundamental processes that structure communities: dispersal, speciation, species-level selection and ecological drift. Our goal is to provide process-based insights into why human impacts, and responses to impacts, may differ across ecosystem types using a mechanistic, eco-evolutionary comparative framework. To enable these insights, we review and synthesise (i) how the four processes influence diversity and dynamics in terrestrial versus freshwater communities, specifically whether the relative importance of each process differs among ecosystems, and (ii) the pathways by which human impacts can produce divergent responses across ecosystems, due to differences in the strength of processes among ecosystems we identify. Finally, we highlight research gaps and next steps, and discuss how this approach can provide new insights for conservation. By focusing on the processes that shape diversity in communities, we aim to mechanistically link human impacts to ongoing and future changes in ecosystems. 相似文献
795.
Livia Zapponi Marta Del Bianco Luca Luiselli Andrea Catorci Marco A. Bologna 《Mammalian Biology》2013,78(3):157-163
The study of the effect of habitat fragmentation on species that inhabit residual patches requires the investigation of the relationship existing between species distribution and landscape components. To understand which components of landscape mosaics are more influential for species’ persistence, we compared the distribution of two arboreal rodents proved to be sensitive to habitat fragmentation, the hazel dormouse Muscardinus avellanarius and the red squirrel Sciurus vulgaris. Their occurrence in residual oak woods in central Italy was studied with nest-boxes and hair-tubes, developing a new method for hair analysis. Their distributions were analysed considering patch, matrix composition and configuration, and landscape vegetation variables. The two species showed a different degree of plasticity, with the squirrel being significantly more specialised at the landscape scale. The comparison of the two distribution patterns highlighted the influence of different ecological constraints and the existence of different strategies to cope with fragmentation. Patch size and patch attributes were generally weaker determinants of occurrence, compared to landscape metrics. The squirrel presence was significantly influenced by the presence of shared perimeter between hedgerows and woods and by the lack of isolation of the residual patches, suggesting the use of several fragments to compensate the low habitat quality. Conversely the hazel dormouse seemed to be more affected by the internal management of the woods, and in particular by the mean DBH. Our results highlight how the recognition of the extrinsic constraints and the influence of multi-scale habitat selection may help guiding land use management, to ensure species conservation in profoundly exploited landscapes. 相似文献
796.
Laure Gallien Rolland Douzet Steve Pratte Niklaus E. Zimmermann Wilfried Thuiller 《Global Ecology and Biogeography》2012,21(11):1126-1136
Aim Two core assumptions of species distribution models (SDMs) do not hold when modelling invasive species. Invasives are not in equilibrium with their environment and niche quantification and transferability in space and time are limited. Here, we test whether combining global‐ and regional‐scale data in a novel framework can overcome these limitations. Beyond simply improving regional niche modelling of non‐native species, the framework also makes use of the violation of regional equilibrium assumptions, and aims at estimating the stage of invasion, range filling and risk of spread in the near future for 27 invasive species in the French Alps. Innovation For each invader we built three sets of SDMs using a committee averaging method: one global model and two regional models (a conventional model and one using the global model output to weight pseudo‐absences). Model performances were compared using the area under the receiver operating characteristic curve, the true skill statistic, sensitivity and specificity scores. Then, we extracted the predictions for observed presences and compared them to global and regional models. This comparison made it possible to identify whether invasive species were observed within or outside of their regional and global niches. Main conclusions This study provides a novel methodological framework for improving the regional modelling of invasive species, where the use of a global model output to weight pseudo‐absences in a regional model significantly improved the predictive performance of regional SDMs. Additionally, the comparison of the global and regional model outputs revealed distinct patterns of niche estimates and range filling among the species. These differences allowed us to draw conclusions about the stage of invasion and the risk of spread in the near future, which both correspond to experts' expectations. This framework can be easily applied to a large number of species and is therefore useful for control of biological invasions and eradication planning. 相似文献
797.
Dominique Germain M. Biasotto Mario Tosi Tommaso Meo Axel Kahn Livia Poenaru 《Human genetics》1996,98(6):719-726
We used the fluorescence-assisted mismatch analysis (FAMA) method to screen rapidly the α-galactosidase A gene in patients
with Fabry disease in order to identify unknown mutations and help define genotype-phenotype correlations in this X-linked
lysosomal storage disorder. Chemical cleavage at mismatches on heteroduplex DNA end-labeled with strand-specific fluorescent
dyes, reliably detects sequence changes in DNA fragments of up to 1.5 kb and locates them precisely. Exhaustive scanning of
the α-galactosidase gene was accomplished on four polymerase chain reaction-generated amplicons, covering all seven exons,
the exon-intron boundaries, and 700 bp of 5′-flanking sequence. Mutations were identified in each of the 15 patients studied
from nine unrelated kindreds. Among the seven previously undescribed sequence changes, three are obviously pathogenic because
they lead to premature protein termination. The other four, a splice-site mutation and three missense mutations, were the
only changes found upon complete scanning of the gene and its promoter. In addition, FAMA also detects female heterozygous
carriers more dependably than direct sequencing, and thus provides a valuable diagnostic test. In Fabry disease, this molecular
criterion is especially important for genetic counseling since heterozygotes can be asymptomatic and their enzymatic values
within the normal range.
Received: 9 April 1996 / Revised: 8 July 1996 相似文献