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31.
Kris Van Looy Jonathan D. Tonkin Mathieu Floury Catherine Leigh Janne Soininen Stefano Larsen Jani Heino N. LeRoy Poff Michael Delong Sonja C. Jhnig Thibault Datry Núria Bonada Juliette Rosebery Aurlien Jamoneau Steve J. Ormerod Kevin J. Collier Christian Wolter 《河流研究与利用》2019,35(2):107-120
Resilience in river ecosystems requires that organisms must persist in the face of highly dynamic hydrological and geomorphological variations. Disturbance events such as floods and droughts are postulated to shape life history traits that support resilience, but river management and conservation would benefit from greater understanding of the emergent effects in communities of river organisms. We unify current knowledge of taxonomic‐, phylogenetic‐, and trait‐based aspects of river communities that might aid the identification and quantification of resilience mechanisms. Temporal variations in river productivity, physical connectivity, and environmental heterogeneity resulting from floods and droughts are highlighted as key characteristics that promote resilience in these dynamic ecosystems. Three community‐wide mechanisms that underlie resilience are (a) partitioning (competition/facilitation) of dynamically varying resources, (b) dispersal, recolonization, and recruitment promoted by connectivity, and (c) functional redundancy in communities promoted by resource heterogeneity and refugia. Along with taxonomic and phylogenetic identity, biological traits related to feeding specialization, dispersal ability, and habitat specialization mediate organism responses to disturbance. Measures of these factors might also enable assessment of the relative contributions of different mechanisms to community resilience. Interactions between abiotic drivers and biotic aspects of resource use, dispersal, and persistence have clear implications for river conservation and management. To support these management needs, we propose a set of taxonomic, phylogenetic, and life‐history trait metrics that might be used to measure resilience mechanisms. By identifying such indicators, our proposed framework can enable targeted management strategies to adapt river ecosystems to global change. 相似文献
32.
Alessia Trimigno Bekzod Khakimov Francesco Savorani Leonardo Tenori Vaiva Hendrixson Alminas ivilis Marija Glibetic Mirjana Gurinovic Saara Pentikinen Janne Sallinen Sara Garduno Diaz Francesca Pasqui Santosh Khokhar Claudio Luchinat Alessandra Bordoni Francesco Capozzi Sren Balling Engelsen 《Molecular nutrition & food research》2019,63(1)
33.
A previous study showed that classical building-related symptoms (BRS) were related to indoor dust and microbial toxicity via boar sperm motility assay, a sensitive method for measuring mitochondrial toxicity. In this cross-sectional study, we analyzed whether teachers’ most common work-related non-literature-known BRS (nBRS) were also associated with dust or microbial toxicity. Teachers from 15 schools in Finland completed a questionnaire evaluating 20 nBRS including general, eye, respiratory, hearing, sleep, and mental symptoms. Boar sperm motility assay was used to measure the toxicity of extracts from wiped dust and microbial fallout samples collected from teachers’ classrooms. 231 teachers answered a questionnaire and their classroom toxicity data were recorded. A negative binomial mixed model showed that teachers’ work-related nBRS were 2.9-fold (95% CI: 1.2-7.3) higher in classrooms with highly toxic dust samples compared to classrooms with non-toxic dust samples (p = 0.024). The RR of work-related nBRS was 1.8 (95% CI: 1.1-2.9) for toxic microbial samples (p = 0.022). Teachers’ BRS appeared to be broader than reported in the literature, and the work-related nBRS were associated with toxic dusts and microbes in classrooms. 相似文献
34.
35.
Sanz-Casado Elías De Filippo Daniela Benavent Rafael Aleixandre Røeggen Vidar Pölönen Janne 《Scientometrics》2021,126(11):9031-9049
Scientometrics - This article analyses the impact and visibility of scholarly journals in the humanities that are publishing in the national languages in Finland, Norway and Spain. Three types of... 相似文献
36.
Karjalainen J Riekkinen O Töyräs J Kröger H Jurvelin J 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2008,55(10):2191-2197
In osteoporosis, total bone mass decreases and the thickness of the cortical layer diminishes in the shafts of the long bones. In this study, a simple ultrasonic in vivo method for determining the thickness of the cortical bone layer was applied, and the suitability of two different signal analysis techniques, i.e., envelope and cepstral methods, for measuring cortical thickness was compared. The values of cortical thickness, as determined with both techniques, showed high linear correlations (r ges 0.95) with the thickness values obtained from in vitro measurements with a caliper or in vivo measurements by peripheral quantitative CT (pQCT). No systematic errors that could be related to the cortical thickness were found. The in vivo accuracy of the measurements was 6.6% and 7.0% for the envelope and cepstral methods, respectively. Further, the in vivo precision for the envelope and cepstral methods was 0.26 mm and 0.28 mm, respectively. Although the results are similar for both of the techniques, the simplicity of the envelope method makes it more attractive for clinical applications. In conclusion, a simple ultrasound measurement provides an accurate estimate of the cortical bone thickness. The techniques investigated may have clinical potential for osteoporosis screening and therefore warrant more extensive clinical investigations with healthy and osteoporotic individuals. 相似文献
37.
Rufus Vinod Randa Mahran Erica Routila Janne Leivo Kim Pettersson Kamlesh Gidwani 《International journal of molecular sciences》2021,22(19)
Extracellular vesicles (EVs) are found in all biological fluids, providing potential for the identification of disease biomarkers such as colorectal cancer (CRC). EVs are heavily glycosylated with specific glycoconjugates such as tetraspanins, integrins, and mucins, reflecting the characteristics of the original cell offering valuable targets for detection of CRC. We report here on europium-nanoparticle (EuNP)-based assay to detect and characterize different surface glycoconjugates of EVs without extensive purification steps from five different CRC and the HEK 293 cell lines. The promising EVs candidates from cell culture were clinically evaluated on small panel of serum samples including early-stage (n = 11) and late-stage (n = 11) CRC patients, benign condition (n = 11), and healthy control (n = 10). The majority of CRC cell lines expressed tetraspanin sub-population and glycovariants of integrins and conventional tumor markers. The subpopulation of CD151 having CD63 expression (CD151CD63) was significantly (p = 0.001) elevated in early-stage CRC (8 out of 11) without detecting any benign and late-stage samples, while conventional CEA detected mostly late-stage CRC (p = 0.045) and with only four early-stage cases. The other glycovariant assays such as CEACon-A, CA125WGA, CA 19.9Ma696, and CA 19.9Con-A further provided some complementation to the CD151CD63 assay. These results indicate the potential application of CD151CD63 assay for early detection of CRC patients in human serum. 相似文献
38.
We introduce an imaging technique based on second-harmonic generation with cylindrical vector beams that is extremely sensitive to three-dimensional orientation and nanoscale morphology of metal nano-objects. Our experiments and second-harmonic field calculations based on frequency-domain boundary element method are in very good agreement. The technique provides contrast for structural features that cannot be resolved by linear techniques or conventional states of polarization and shows great potential for simple and cost-effective far-field optical imaging in plasmonics. 相似文献
39.
In the past few years extensive discussions on bioenergy has been both positive and negative. In Europe, the image of bioenergy appears to be low with lack of broad public support. Previous studies show that younger people are unsure about many issues surrounding renewable energy. The aim of this study was to investigate the knowledge and perceptions of bioenergy among pupils in North Karelia, Finland. Data drawn from 495 ninth grade students indicate that the majority of them lack in-depth knowledge about different renewable energy sources, including bioenergy. Only a small percentage has a ‘high’ level of knowledge about bioenergy and the majority indicates critical perceptions of it. Statistically significant gender differences are not apparent. Girls appear to be more knowledgeable than boys. Results also show a clear ‘urban’ and ‘rural’ difference in perceptions of bioenergy. Perceptions of urban respondents being more positive than that of their rural counterparts. Developing collaboration between future bioenergy policies and bioenergy education for younger citizens is necessary for their engagement in critical debates on bioenergy. 相似文献
40.
Coating of micrometer-sized particles of salbutamol sulphate or sodium chloride with the amino acid l-leucine in the gas phase is described. A novel method to synthesize core particles and coat them with l-leucine simultaneously was carried out in an aerosol flow reactor. The coating was prepared via temperature-induced heterogeneous nucleation of l-leucine vapor on the 0.6-1.0 µm core particles, and subsequent growth of l-leucine crystals by physical vapor deposition. The core salbutamol particles were amorphous, whereas the NaCl core particles were crystalline. The l-leucine sublimation that took place at 140-195 °C depended on the identity of the core material due to (i) molecular interaction and (ii) phase mixing. The former was dominant with salbutamol/l-leucine particles and the latter was dominant with NaCl/l-leucine particles. During the vapor deposition, l-leucine formed a discontinuous coating layer of leafy-looking crystallites, with sizes from a few nanometers to hundreds of nanometers, pointing out from the core particle surface. The l-leucine deposition properties depended on the core morphology: l-leucine crystallites were distributed more evenly on salbutamol core surfaces than on salt core surfaces, where the crystallites were localized mainly on edges. The stability of coated salbutamol particles was retained during storage under humid conditions. 相似文献