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1.
  • Schael, S, et al. (author)
  • Precision electroweak measurements on the Z resonance
  • 2006
  • In: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
  • Research review (peer-reviewed)abstract
    • We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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  • 2019
  • Journal article (peer-reviewed)
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  • Thomas, H. J. D., et al. (author)
  • Global plant trait relationships extend to the climatic extremes of the tundra biome
  • 2020
  • In: Nature Communications. - : Nature Publishing Group. - 2041-1723. ; 11:1
  • Journal article (peer-reviewed)abstract
    • The majority of variation in six traits critical to the growth, survival and reproduction of plant species is thought to be organised along just two dimensions, corresponding to strategies of plant size and resource acquisition. However, it is unknown whether global plant trait relationships extend to climatic extremes, and if these interspecific relationships are confounded by trait variation within species. We test whether trait relationships extend to the cold extremes of life on Earth using the largest database of tundra plant traits yet compiled. We show that tundra plants demonstrate remarkably similar resource economic traits, but not size traits, compared to global distributions, and exhibit the same two dimensions of trait variation. Three quarters of trait variation occurs among species, mirroring global estimates of interspecific trait variation. Plant trait relationships are thus generalizable to the edge of global trait-space, informing prediction of plant community change in a warming world.
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  • Thomas, H. J.D., et al. (author)
  • Traditional plant functional groups explain variation in economic but not size-related traits across the tundra biome
  • 2019
  • In: Global Ecology and Biogeography. - : Wiley. - 1466-822X .- 1466-8238. ; 28:2, s. 78-95
  • Journal article (peer-reviewed)abstract
    • © 2018 The Authors Global Ecology and Biogeography Published by John Wiley & Sons Ltd Aim: Plant functional groups are widely used in community ecology and earth system modelling to describe trait variation within and across plant communities. However, this approach rests on the assumption that functional groups explain a large proportion of trait variation among species. We test whether four commonly used plant functional groups represent variation in six ecologically important plant traits. Location: Tundra biome. Time period: Data collected between 1964 and 2016. Major taxa studied: 295 tundra vascular plant species. Methods: We compiled a database of six plant traits (plant height, leaf area, specific leaf area, leaf dry matter content, leaf nitrogen, seed mass) for tundra species. We examined the variation in species-level trait expression explained by four traditional functional groups (evergreen shrubs, deciduous shrubs, graminoids, forbs), and whether variation explained was dependent upon the traits included in analysis. We further compared the explanatory power and species composition of functional groups to alternative classifications generated using post hoc clustering of species-level traits. Results: Traditional functional groups explained significant differences in trait expression, particularly amongst traits associated with resource economics, which were consistent across sites and at the biome scale. However, functional groups explained 19% of overall trait variation and poorly represented differences in traits associated with plant size. Post hoc classification of species did not correspond well with traditional functional groups, and explained twice as much variation in species-level trait expression. Main conclusions: Traditional functional groups only coarsely represent variation in well-measured traits within tundra plant communities, and better explain resource economic traits than size-related traits. We recommend caution when using functional group approaches to predict tundra ecosystem change, or ecosystem functions relating to plant size, such as albedo or carbon storage. We argue that alternative classifications or direct use of specific plant traits could provide new insight into ecological prediction and modelling.
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  • Björkman, Anne, 1981, et al. (author)
  • Plant functional trait change across a warming tundra biome
  • 2018
  • In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 562:7725, s. 57-62
  • Journal article (peer-reviewed)abstract
    • The tundra is warming more rapidly than any other biome on Earth, and the potential ramifications are far-reaching because of global feedback effects between vegetation and climate. A better understanding of how environmental factors shape plant structure and function is crucial for predicting the consequences of environmental change for ecosystem functioning. Here we explore the biome-wide relationships between temperature, moisture and seven key plant functional traits both across space and over three decades of warming at 117 tundra locations. Spatial temperature–trait relationships were generally strong but soil moisture had a marked influence on the strength and direction of these relationships, highlighting the potentially important influence of changes in water availability on future trait shifts in tundra plant communities. Community height increased with warming across all sites over the past three decades, but other traits lagged far behind predicted rates of change. Our findings highlight the challenge of using space-for-time substitution to predict the functional consequences of future warming and suggest that functions that are tied closely to plant height will experience the most rapid change. They also reveal the strength with which environmental factors shape biotic communities at the coldest extremes of the planet and will help to improve projections of functional changes in tundra ecosystems with climate warming.
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  • Barrio, Isabel C., et al. (author)
  • Background invertebrate herbivory on dwarf birch (Betula glandulosa-nana complex) increases with temperature and precipitation across the tundra biome
  • 2017
  • In: Polar Biology. - : Springer. - 0722-4060 .- 1432-2056. ; 40:11, s. 2265-2278
  • Journal article (peer-reviewed)abstract
    • Chronic, low intensity herbivory by invertebrates, termed background herbivory, has been understudied in tundra, yet its impacts are likely to increase in a warmer Arctic. The magnitude of these changes is however hard to predict as we know little about the drivers of current levels of invertebrate herbivory in tundra. We assessed the intensity of invertebrate herbivory on a common tundra plant, the dwarf birch (Betula glandulosa-nana complex), and investigated its relationship to latitude and climate across the tundra biome. Leaf damage by defoliating, mining and gall-forming invertebrates was measured in samples collected from 192 sites at 56 locations. Our results indicate that invertebrate herbivory is nearly ubiquitous across the tundra biome but occurs at low intensity. On average, invertebrates damaged 11.2% of the leaves and removed 1.4% of total leaf area. The damage was mainly caused by external leaf feeders, and most damaged leaves were only slightly affected (12% leaf area lost). Foliar damage was consistently positively correlated with mid-summer (July) temperature and, to a lesser extent, precipitation in the year of data collection, irrespective of latitude. Our models predict that, on average, foliar losses to invertebrates on dwarf birch are likely to increase by 6-7% over the current levels with a 1 degrees C increase in summer temperatures. Our results show that invertebrate herbivory on dwarf birch is small in magnitude but given its prevalence and dependence on climatic variables, background invertebrate herbivory should be included in predictions of climate change impacts on tundra ecosystems.
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  • Björkman, Anne, 1981, et al. (author)
  • Tundra Trait Team: A database of plant traits spanning the tundra biome
  • 2018
  • In: Global Ecology and Biogeography. - : Wiley. - 1466-822X .- 1466-8238. ; 27:12, s. 1402-1411
  • Journal article (peer-reviewed)abstract
    • © 2018 The Authors Global Ecology and Biogeography Published by John Wiley & Sons Ltd Motivation: The Tundra Trait Team (TTT) database includes field-based measurements of key traits related to plant form and function at multiple sites across the tundra biome. This dataset can be used to address theoretical questions about plant strategy and trade-offs, trait–environment relationships and environmental filtering, and trait variation across spatial scales, to validate satellite data, and to inform Earth system model parameters. Main types of variable contained: The database contains 91,970 measurements of 18 plant traits. The most frequently measured traits (>1,000 observations each) include plant height, leaf area, specific leaf area, leaf fresh and dry mass, leaf dry matter content, leaf nitrogen, carbon and phosphorus content, leaf C:N and N:P, seed mass, and stem specific density. Spatial location and grain: Measurements were collected in tundra habitats in both the Northern and Southern Hemispheres, including Arctic sites in Alaska, Canada, Greenland, Fennoscandia and Siberia, alpine sites in the European Alps, Colorado Rockies, Caucasus, Ural Mountains, Pyrenees, Australian Alps, and Central Otago Mountains (New Zealand), and sub-Antarctic Marion Island. More than 99% of observations are georeferenced. Time period and grain: All data were collected between 1964 and 2018. A small number of sites have repeated trait measurements at two or more time periods. Major taxa and level of measurement: Trait measurements were made on 978 terrestrial vascular plant species growing in tundra habitats. Most observations are on individuals (86%), while the remainder represent plot or site means or maximums per species. Software format: csv file and GitHub repository with data cleaning scripts in R; contribution to TRY plant trait database (www.try-db.org) to be included in the next version release.
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  • Lindén, Elin, et al. (author)
  • Circum-Arctic distribution of chemical anti-herbivore compounds suggests biome-wide trade-off in defence strategies in Arctic shrubs
  • 2022
  • In: Ecography. - : John Wiley & Sons. - 0906-7590 .- 1600-0587. ; :11
  • Journal article (peer-reviewed)abstract
    • Spatial variation in plant chemical defence towards herbivores can help us understand variation in herbivore top–down control of shrubs in the Arctic and possibly also shrub responses to global warming. Less defended, non-resinous shrubs could be more influenced by herbivores than more defended, resinous shrubs. However, sparse field measurements limit our current understanding of how much of the circum-Arctic variation in defence compounds is explained by taxa or defence functional groups (resinous/non-resinous). We measured circum-Arctic chemical defence and leaf digestibility in resinous (Betula glandulosa, B. nana ssp. exilis) and non-resinous (B. nana ssp. nana, B. pumila) shrub birches to see how they vary among and within taxa and functional groups. Using liquid chromatography–mass spectrometry (LC–MS) metabolomic analyses and in vitro leaf digestibility via incubation in cattle rumen fluid, we analysed defence composition and leaf digestibility in 128 samples from 44 tundra locations.We found biogeographical patterns in anti-herbivore defence where mean leaf triterpene concentrations and twig resin gland density were greater in resinous taxa and mean concentrations of condensing tannins were greater in non-resinous taxa. This indicates a biome-wide trade-off between triterpene- or tannin-dominated defences. However, we also found variations in chemical defence composition and resin gland density both within and among functional groups (resinous/non-resinous) and taxa, suggesting these categorisations only partly predict chemical herbivore defence. Complex tannins were the only defence compounds negatively related to in vitro digestibility, identifying this previously neglected tannin group as having a potential key role in birch anti-herbivore defence.We conclude that circum-Arctic variation in birch anti-herbivore defence can be partly derived from biogeographical distributions of birch taxa, although our detailed mapping of plant defence provides more information on this variation and can be used for better predictions of herbivore effects on Arctic vegetation.
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  • Myers-Smith, Isla H., et al. (author)
  • Complexity revealed in the greening of the Arctic
  • 2020
  • In: Nature Climate Change. - : Springer Science and Business Media LLC. - 1758-678X .- 1758-6798. ; 10:2, s. 106-117
  • Journal article (peer-reviewed)abstract
    • As the Arctic warms, vegetation is responding, and satellite measures indicate widespread greening at high latitudes. This ‘greening of the Arctic’ is among the world’s most important large-scale ecological responses to global climate change. However, a consensus is emerging that the underlying causes and future dynamics of so-called Arctic greening and browning trends are more complex, variable and inherently scale-dependent than previously thought. Here we summarize the complexities of observing and interpreting high-latitude greening to identify priorities for future research. Incorporating satellite and proximal remote sensing with in-situ data, while accounting for uncertainties and scale issues, will advance the study of past, present and future Arctic vegetation change.
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  • Normand, AC, et al. (author)
  • Clinical Origin and Species Distribution of Fusarium spp. Isolates Identified by Molecular Sequencing and Mass Spectrometry: A European Multicenter Hospital Prospective Study
  • 2021
  • In: Journal of fungi (Basel, Switzerland). - : MDPI AG. - 2309-608X. ; 7:4
  • Journal article (peer-reviewed)abstract
    • Fusarium spp. are widespread environmental fungi as well as pathogens that can affect plants, animals and humans. Yet the epidemiology of human fusariosis is still cloudy due to the rapidly evolving taxonomy. The Mass Spectrometry Identification database (MSI) has been developed since 2017 in order to allow a fast, accurate and free-access identification of fungi by matrix-assisted laser desorption ionization—time of flight (MALDI-TOF) mass spectrometry. Taking advantage of the MSI database user network, we aim to study the species distribution of Fusarium spp. isolates in an international multicenter prospective study. This study also allowed the assessment of the abilities of miscellaneous techniques to identify Fusarium isolates at the species level. The identification was performed by PCR-sequencing and phylogenic-tree approach. Both methods are used as gold standard for the evaluation of mass spectrometry. Identification at the species complex was satisfactory for all the tested methods. However, identification at the species level was more challenging and only 32% of the isolates were correctly identified with the National Center for Biotechnology Information (NCBI) DNA database, 20% with the Bruker MS database and 43% with the two MSI databases. Improvement of the mass spectrometry database is still needed to enable precise identification at the species level of any Fusarium isolates encountered either in human pathology or in the environment.
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  • Brusich, S, et al. (author)
  • Croatian National Data and Comparison with European Practice: Data from the Cardiac Resynchronization Therapy Survey II Multicenter Registry
  • 2018
  • In: Cardiology research and practice. - : Hindawi Limited. - 2090-8016 .- 2090-0597. ; 2018, s. 3479846-
  • Journal article (peer-reviewed)abstract
    • Aims. The Cardiac Resynchronization Therapy (CRT) Survey II was conducted between October 2015 and December 2016 and included data from 11088 CRT implantations from 42 countries. The survey’s aim was to report on current European CRT practice. The aim of this study was to compare the Croatian national CRT practice with the European data. Methods. Five centres from Croatia recruited consecutive patients, in a 15-month period, who underwent CRT implantation, primary or an upgrade. Data were collected prospectively by using online database. Results. A total of 115 patients were included in Croatia, which is 33.2% of all CRT implants in Croatia during the study period (total n=346). Median age of the study population was 67 (61–73) years, and 21.2% were women. Primary heart failure (HF) aetiology was nonischemic in 61.1% of patients, and HF with wide QRS was the most common indication for the implantation (73.5%). 80% of patients had complete left bundle branch block, and over two-third had QRS ≥150 ms. Device-related adverse events were recorded in 4.3% of patients. When compared with European countries, Croatian patients were significantly younger (67 vs. 70 years, p=0.012), had similar rate of comorbidities with the exception of higher prevalence of hypertension. Croatian patients significantly more often received CRT-pacemaker when compared with European population (58.3 vs. 29.9%, OR 3.27, 95%CI 2.25–4.74, p<0.001). Conclusion. Our data indicate strict selection of patients among HF population and adherence to guidelines with exception of higher proportion of CRT-pacemaker implantation. This is likely to be influenced by healthcare organization and reimbursement issues in Croatia.
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  • Criado, M. G., et al. (author)
  • Plant traits poorly predict winner and loser shrub species in a warming tundra biome
  • 2023
  • In: Nature Communications. - 2041-1723. ; 14:1
  • Journal article (peer-reviewed)abstract
    • Climate change is leading to species redistributions. In the tundra biome, shrubs are generally expanding, but not all tundra shrub species will benefit from warming. Winner and loser species, and the characteristics that may determine success or failure, have not yet been fully identified. Here, we investigate whether past abundance changes, current range sizes and projected range shifts derived from species distribution models are related to plant trait values and intraspecific trait variation. We combined 17,921 trait records with observed past and modelled future distributions from 62 tundra shrub species across three continents. We found that species with greater variation in seed mass and specific leaf area had larger projected range shifts, and projected winner species had greater seed mass values. However, trait values and variation were not consistently related to current and projected ranges, nor to past abundance change. Overall, our findings indicate that abundance change and range shifts will not lead to directional modifications in shrub trait composition, since winner and loser species share relatively similar trait spaces. Functional trait data could guide predictions of species responses to environmental change. Here, the authors show that winner and loser shrub species in the warming tundra biome overlap in trait space and may therefore be difficult to predict based on commonly measured traits.
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  • Heindel, Jerrold J., et al. (author)
  • Obesity II : Establishing causal links between chemical exposures and obesity
  • 2022
  • In: Biochemical Pharmacology. - : Elsevier. - 0006-2952 .- 1356-1839 .- 1873-2968. ; 199
  • Research review (peer-reviewed)abstract
    • Obesity is a multifactorial disease with both genetic and environmental components. The prevailing view is that obesity results from an imbalance between energy intake and expenditure caused by overeating and insufficient exercise. We describe another environmental element that can alter the balance between energy intake and energy expenditure: obesogens. Obesogens are a subset of environmental chemicals that act as endocrine disruptors affecting metabolic endpoints. The obesogen hypothesis posits that exposure to endocrine disruptors and other chemicals can alter the development and function of the adipose tissue, liver, pancreas, gastrointestinal tract, and brain, thus changing the set point for control of metabolism. Obesogens can determine how much food is needed to maintain homeostasis and thereby increase the susceptibility to obesity. The most sensitive time for obesogen action is in utero and early childhood, in part via epigenetic programming that can be transmitted to future generations. This review explores the evidence supporting the obesogen hypothesis and highlights knowledge gaps that have prevented widespread acceptance as a contributor to the obesity pandemic. Critically, the obesogen hypothesis changes the narrative from curing obesity to preventing obesity.
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  • Iovev, S, et al. (author)
  • EUROPEAN CRT SURVEY II - BULGARIAN DATA
  • 2018
  • In: COMPTES RENDUS DE L ACADEMIE BULGARE DES SCIENCES. - 1310-1331. ; 71:6, s. 859-864
  • Journal article (other academic/artistic)
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  • Tajima, Toshiki, et al. (author)
  • Science of Extreme Light Infrastructure
  • 2010
  • In: LIGHT AT EXTREME INTENSITIES. - : AIP. - 9780735407718 ; , s. 11-35
  • Conference paper (peer-reviewed)abstract
    • The infrastructure of Extreme Light Infrastructure (ELI) provides an unprecedented opportunity for a broad range of frontier science. Its highest ever intensity of lasers, as well as high fluence, high power, and/or ultrafast optical characteristics carve out new territories of discovery, ranging from attosecond science to photonuclear science, laser acceleration and associated beams, and high field science (Four Pillars of ELI). Its applications span from medicine, biology, engineering, energy, chemistry, physics, and fundamental understanding of the Universe. The relativistic optics that intense lasers have begun exploring may be extended into a new regime of ultra-relativistic regime, where even protons fly relativistically in the optical fields. ELI provides the highest intensity to date such that photon fields begin to feel even the texture of vacuum. This is a singular appeal of ELI with its relatively modest infrastructure (compared to the contemporary largest scientific infrastructures), yet provides an exceptional avenue along which the 21(st) Century science and society need to answer the toughest questions. The intensity frontier simultaneously brings in the energy horizon (TeV and PeV) as well as temporal frontier (attoseconds and zeptoseconds). It also turns over optics of atoms and molecules into that of nuclei with the ability to produce monoenergetic collimated gamma-ray photons. As such, the ELI concept acutely demands an effort to encompass and integrate its Four Pillars.
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  • Blaak, E E, et al. (author)
  • Impact of postprandial glycaemia on health and prevention of disease.
  • 2012
  • In: Obesity Reviews. - 1467-7881. ; 13:10, s. 923-984
  • Journal article (peer-reviewed)abstract
    • Postprandial glucose, together with related hyperinsulinemia and lipidaemia, has been implicated in the development of chronic metabolic diseases like obesity, type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). In this review, available evidence is discussed on postprandial glucose in relation to body weight control, the development of oxidative stress, T2DM, and CVD and in maintaining optimal exercise and cognitive performance. There is mechanistic evidence linking postprandial glycaemia or glycaemic variability to the development of these conditions or in the impairment in cognitive and exercise perfomance. Nevertheless, postprandial glycaemia is interrelated with many other (risk) factors as well as to fasting glucose. In many studies, meal-related glycaemic response is not sufficiently characterized, or the methodology with respect to the description of food or meal composition, or the duration of the measurement of postprandial glycaemia is limited. It is evident that more randomized controlled dietary intervention trials using effective low vs. high glucose response diets are necessary in order to draw more definite conclusions on the role of postprandial glycaemia in relation to health and disease. Also of importance is the evaluation of the potential role of the time course of postprandial glycaemia.
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  • Chadwick, D., et al. (author)
  • Digital inclusion and participation of people with intellectual disabilities during COVID-19 : A rapid review and international bricolage
  • 2022
  • In: Journal of Policy and Practice in Intellectual Disabilities. - : Wiley. - 1741-1122 .- 1741-1130. ; 19:3, s. 242-256
  • Journal article (peer-reviewed)abstract
    • The COVID-19 pandemic has meant a rapid transfer of everyday activities to the online world. Information and communication technologies (ICTs) have become more embedded than ever in people's lives. This investigation addresses how this change has affected the lives of people with intellectual disabilities (ID). A two-step design was used. A rapid review was conducted on empirical studies published between January 2019 and June 2021. Search terms related to ID, ICT use and COVID-19. A qualitative international bricolage was also conducted corresponding to author nationalities. Data gathered from the review and bricolage were analysed separately using thematic analysis and relationally synthesised. Digital solutions to provide access to COVID-19 information and guidance seemed inadequate but were seldom empirically studied. Digital poverty, literacy and exclusion remain significant issues for people with ID internationally. People and their carers experienced reduced and removed service provision, loneliness and impoverished daily lives during the pandemic; amelioration of which was facilitated by digital solutions. One solution often used was videoconferencing. Prior experience of digital participation, adequate finances, connection, support and digital literacy mentoring for both people with ID and those providing services and support facilitated digital inclusion. Digital exclusion during COVID-19 was exacerbated by sociopolitical, structural, individual and support-related barriers. Although awareness of digital exclusion appears to have been raised, the extent to which this has led to action and change remains unclear. Despite digital exclusion and digital participation benefitting continuation of life, social and emotional well-being and autonomy, COVID-19 has not provided the impetus to eradicate digital poverty for people with ID. Governmental support, digital education, creativity and problem solving are required to enable people with ID the human right to be included in the digital world at this essential time and into the future.
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  • Grijseels, S., et al. (author)
  • Identification of the decumbenone biosynthetic gene cluster in penicillium decumbens and the importance for production of calbistrin
  • 2018
  • In: Fungal Biology and Biotechnology. - : Springer Science and Business Media LLC. - 2054-3085. ; 5:1, s. 1-17
  • Journal article (peer-reviewed)abstract
    • Background: Filamentous fungi are important producers of secondary metabolites, low molecular weight molecules that often have bioactive properties. Calbistrin A is a secondary metabolite with an interesting structure that was recently found to have bioactivity against leukemia cells. It consists of two polyketides linked by an ester bond: a bicy-clic decalin containing polyketide with structural similarities to lovastatin, and a linear 12 carbon dioic acid structure. Calbistrin A is known to be produced by several uniseriate black Aspergilli, Aspergillus versicolor-related species, and Penicillia. Penicillium decumbens produces calbistrin A and B as well as several putative intermediates of the calbistrin pathway, such as decumbenone A-B and versiol. Results: A comparative genomics study focused on the polyketide synthase (PKS) sets found in three full genome sequence calbistrin producing fungal species, P. decumbens, A. aculeatus and A. versicolor, resulted in the identification of a novel, putative 13-membered calbistrin producing gene cluster (calA to calM). Implementation of the CRISPR/ Cas9 technology in P. decumbens allowed the targeted deletion of genes encoding a polyketide synthase (calA), a major facilitator pump (calB) and a binuclear zinc cluster transcription factor (calC). Detailed metabolic profiling, using UHPLC-MS, of the ∆calA (PKS) and ∆calC ( TF) strains confirmed the suspected involvement in calbistrin productions as neither strains produced calbistrin nor any of the putative intermediates in the pathway. Similarly analysis of the excreted metabolites in the ∆calB (MFC-pump) strain showed that the encoded pump was required for efficient export of calbistrin A and B. Conclusion: Here we report the discovery of a gene cluster (calA-M) involved in the biosynthesis of the polyketide calbistrin in P. decumbens. Targeted gene deletions proved the involvement of CalA (polyketide synthase) in the biosynthesis of calbistrin, CalB (major facilitator pump) for the export of calbistrin A and B and CalC for the transcriptional regulation of the cal-cluster. This study lays the foundation for further characterization of the calbistrin biosynthetic pathway in multiple species and the development of an efficient calbistrin producing cell factory.
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  • Grijseels, S., et al. (author)
  • Physiological characterization of secondary metabolite producing Penicillium cell factories
  • 2017
  • In: Fungal Biology and Biotechnology. - : Springer Science and Business Media LLC. - 2054-3085. ; 4, s. 8-
  • Journal article (peer-reviewed)abstract
    • Background: Penicillium species are important producers of bioactive secondary metabolites. However, the immense diversity of the fungal kingdom is only scarcely represented in industrial bioprocesses and the upscaling of compound production remains a costly and labor intensive challenge. In order to facilitate the development of novel secondary metabolite producing processes, two routes are typically explored: optimization of the native producer or transferring the enzymatic pathway into a heterologous host. Recent genome sequencing of ten Penicillium species showed the vast amount of secondary metabolite gene clusters present in their genomes, and makes them accessible for rational strain improvement. In this study, we aimed to characterize the potential of these ten Penicillium species as native producing cell factories by testing their growth performance and secondary metabolite production in submerged cultivations.Results: Cultivation of the fungal species in controlled submerged bioreactors showed that the ten wild type Penicillium species had promising, highly reproducible growth characteristics in two different media. Analysis of the secondary metabolite production using liquid chromatography coupled with high resolution mass spectrometry proved that the species produced a broad range of secondary metabolites, at different stages of the fermentations. Metabolite profiling for identification of the known compounds resulted in identification of 34 metabolites; which included several with bioactive properties such as antibacterial, antifungal and anticancer activities. Additionally, several novel species metabolite relationships were found.Conclusions: This study demonstrates that the fermentation characteristics and the highly reproducible performance in bioreactors of ten recently genome sequenced Penicillium species should be considered as very encouraging for the application of native hosts for production via submerged fermentation. The results are particularly promising for the potential development of the ten analysed Penicillium species for production of novel bioactive compounds via submerged fermentations
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  • Herrera-Belaroussi, Aude, et al. (author)
  • Candidatus Frankia nodulisporulans sp. nov., an Alnus glutinosa-infective Frankia species unable to grow in pure culture and able to sporulate in-planta
  • 2020
  • In: Systematic and Applied Microbiology. - : Elsevier BV. - 0723-2020 .- 1618-0984. ; 43:6
  • Journal article (peer-reviewed)abstract
    • We describe a new Frankia species, for three non-isolated strains obtained from Alnus glutinosa in France and Sweden, respectively. These strains can nodulate several Alnus species (A. glutinosa, A. incana, A. alno-betula), they form hyphae, vesicles and sporangia in the root nodule cortex but have resisted all attempts at isolation in pure culture. Their genomes have been sequenced, they are significantly smaller than those of other Alnus-infective species (5 Mb instead of 7.5 Mb) and are very closely related to one another (ANI of 100%). The name Candidatus Frankia nodulisporulans is proposed.
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  • Koliopoulou, S, et al. (author)
  • Metal nano-floating gate memory devices fabricated at low temperature
  • 2006
  • In: Microelectronic Engineering. - : Elsevier BV. - 0167-9317 .- 1873-5568. ; 83:4-9, s. 1563-1566
  • Journal article (peer-reviewed)abstract
    • In this communication, we report on the realization of low-temperature processed Electrically Erasable Programmable Read-Only Memory (EEPROM) like device with embedded gold nanoparticles. The realization is based on the fabrication of a V-groove SiGe Metal Oxide Semiconductor Field Effect Transistor (MOSFET), the functionalization of a gate oxide followed by self-assembly of gold nanoparticles and finally, the deposition of an organic insulator by Langmuir-Blodgett (LB) technique. Such structures were processed at a temperature lower than 400 degrees C. The electrical characteristics of the final hybrid Metal Insulator Semiconductor FET (MISFET) memory cells were evaluated in terms of memory window and program/erase voltage pulses. A model describing the memory characteristics, based on the electronic properties of the gate stack materials, is presented.
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49.
  • Lazar, J., et al. (author)
  • Human-computer interaction and international public policymaking : A framework for understanding and taking future actions
  • 2015
  • In: Foundations and Trends in Human-Computer Interaction. - : Now Publishers Inc.. - 1551-3955 .- 1551-3963. ; 9:2, s. 69-149
  • Journal article (peer-reviewed)abstract
    • This monograph lays out a discussion framework for understanding the role of human-computer interaction (HCI) in public policymaking. We take an international view, discussing potential areas for research and application, and their potential for impact. Little has been written about the intersection of HCI and public policy; existing reports typically focus on one specific policy issue or incident. To date, there has been no overarching view of the areas of existing impact and potential impact. We have begun that analysis and argue here that such a global view is needed. Our aims are to provide a solid foundation for discussion, cooperation and collaborative interaction, and to outline future programs of activity. The five sections of this report provide relevant background along with a preliminary version of what we expect to be an evolving framework. Sections 1 and 2 provides an introduction to HCI and public policy. Section 3 discusses how HCI already informs public policy, with representative examples. Section 4 discusses how public policy influences HCI and provides representative public policy areas relevant to HCI, where HCI could have even more impact in the future: (i) laws, regulations, and guidelines for HCI research, (ii) HCI research assessments, (iii) research funding, (iv) laws for interface design - accessibility and language, (v) data privacy laws and regulations, (vi) intellectual property, and (vii) laws and regulations in specific sectors. There is a striking difference between where the HCI community has had impact (Section 3) and the many areas of potential involvement (Section 4). Section 5 a framework for action by the HCI community in public policy internationally. This monograph summarizes the observations and recommendations from a daylong workshop at the CHI 2013 conference in Paris, France. The workshop invited the community's perspectives regarding the intersection of governmental policies, international and domestic standards, recent HCI research discoveries, and emergent considerations and challenges. It also incorporates contributions made after the workshop by workshop participants and by individuals who were unable to participate in the workshop but whose work and interests were highly related and relevant.
  •  
50.
  • Normand, Philippe, et al. (author)
  • Genome characteristics of facultatively symbiotic Frankia sp. strains reflect host range and host plant biogeography.
  • 2007
  • In: Genome Research. - : Cold Spring Harbor Laboratory. - 1088-9051. ; 17:1, s. 7-15
  • Journal article (peer-reviewed)abstract
    • Soil bacteria that also form mutualistic symbioses in plants encounter two major levels of selection. One occurs during adaptation to and survival in soil, and the other occurs in concert with host plant speciation and adaptation. Actinobacteria from the genus Frankia are facultative symbionts that form N2-fixing root nodules on diverse and globally distributed angiosperms in the "actinorhizal" symbioses. Three closely related clades of Frankia sp. strains are recognized; members of each clade infect a subset of plants from among eight angiosperm families. We sequenced the genomes from three strains; their sizes varied from 5.43 Mbp for a narrow host range strain (Frankia sp. strain HFPCcI3) to 7.50 Mbp for a medium host range strain (Frankia alni strain ACN14a) to 9.04 Mbp for a broad host range strain (Frankia sp. strain EAN1pec.) This size divergence is the largest yet reported for such closely related soil bacteria (97.8%–98.9% identity of 16S rRNA genes). The extent of gene deletion, duplication, and acquisition is in concert with the biogeographic history of the symbioses and host plant speciation. Host plant isolation favored genome contraction, whereas host plant diversification favored genome expansion. The results support the idea that major genome expansions as well as reductions can occur in facultative symbiotic soil bacteria as they respond to new environments in the context of their symbioses.
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