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1.
  • Andersson, Jan, et al. (author)
  • Fisk- och skaldjursbestånd i hav och sötvatten 2015 : Resursöversikt
  • 2015
  • Reports (other academic/artistic)abstract
    • I rapporten kan du ta del av bedömningen som görs av situationen för bestånd som regleras inom ramen för EU:s gemensamma fiskeripolitik (GFP). Bedömningarna baseras på det forskningssamarbete och den rådgivning som sker inom det Internationella Havsforskningsrådet (ICES).De bestånd som förvaltas nationellt baseras på de biologiska underlagen och rådgivningen i huvudsak på den forskning och övervakning samt analys som bedrivs av Institutionen för akvatiska resurser (SLU Aqua) vid Sveriges lantbruksuniversitet (SLU) samt yrkesfiskets rapportering.Rapporten omfattar 40 fiskarter uppdelade i olika bestånd, samt sex skal-och blötdjursarter.Nytt för årets upplaga är en beskrivning av hur de provfisken som ligger till grund för analys och rådgivning utförs.Översikten är utarbetad av Sveriges lantbruksuniversitet (SLU), Institutionen för akvatiska resurser (SLU Aqua), på uppdrag av Havs- och vattenmyndigheten.
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2.
  • Menkveld, Albert J., et al. (author)
  • Nonstandard Errors
  • 2024
  • In: JOURNAL OF FINANCE. - : Wiley-Blackwell. - 0022-1082 .- 1540-6261. ; 79:3, s. 2339-2390
  • Journal article (peer-reviewed)abstract
    • In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty-nonstandard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for more reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants.
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3.
  • Schafmayer, Clemens, et al. (author)
  • Genome-wide association analysis of diverticular disease points towards neuromuscular, connective tissue and epithelial pathomechanisms
  • 2019
  • In: Gut. - : BMJ. - 0017-5749 .- 1468-3288. ; 68:5, s. 854-865
  • Journal article (peer-reviewed)abstract
    • Objective Diverticular disease is a common complex disorder characterised by mucosal outpouchings of the colonic wall that manifests through complications such as diverticulitis, perforation and bleeding. We report the to date largest genome-wide association study (GWAS) to identify genetic risk factors for diverticular disease. Design Discovery GWAS analysis was performed on UK Biobank imputed genotypes using 31 964 cases and 419 135 controls of European descent. Associations were replicated in a European sample of 3893 cases and 2829 diverticula-free controls and evaluated for risk contribution to diverticulitis and uncomplicated diverticulosis. Transcripts at top 20 replicating loci were analysed by real-time quatitative PCR in preparations of the mucosal, submucosal and muscular layer of colon. The localisation of expressed protein at selected loci was investigated by immunohistochemistry. Results We discovered 48 risk loci, of which 12 are novel, with genome-wide significance and consistent OR in the replication sample. Nominal replication (p< 0.05) was observed for 27 loci, and additional 8 in meta-analysis with a population-based cohort. The most significant novel risk variant rs9960286 is located near CTAGE1 with a p value of 2.3x10-10 and 0.002 (OR allelic = 1.14 (95% CI 1.05 to 1.24)) in the replication analysis. Four loci showed stronger effects for diverticulitis, PHGR1 (OR 1.32, 95% CI 1.12 to 1.56), FAM155A-2 (OR 1.21, 95% CI 1.04 to 1.42), CALCB (OR 1.17, 95% CI 1.03 to 1.33) and S100A10 (OR 1.17, 95% CI 1.03 to 1.33). Conclusion I n silico analyses point to diverticulosis primarily as a disorder of intestinal neuromuscular function and of impaired connective fibre support, while an additional diverticulitis risk might be conferred by epithelial dysfunction.
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4.
  • Afzelius, Mikael, et al. (author)
  • Demonstration of Atomic Frequency Comb Memory for Light with Spin-Wave Storage
  • 2010
  • In: Physical Review Letters. - 1079-7114. ; 104:4
  • Journal article (peer-reviewed)abstract
    • We present a light-storage experiment in a praseodymium-doped crystal where the light is mapped onto an inhomogeneously broadened optical transition shaped into an atomic frequency comb. After absorption of the light, the optical excitation is converted into a spin-wave excitation by a control pulse. A second control pulse reads the memory (on-demand) by reconverting the spin-wave excitation to an optical one, where the comb structure causes a photon-echo-type rephasing of the dipole moments and directional retrieval of the light. This combination of photon-echo and spin-wave storage allows us to store submicrosecond (450 ns) pulses for up to 20 mu s. The scheme has a high potential for storing multiple temporal modes in the single-photon regime, which is an important resource for future long-distance quantum communication based on quantum repeaters.
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5.
  • Alqedra, Mohammed K., et al. (author)
  • Optical coherence properties of Kramers' rare-earth ions at the nanoscale for quantum applications
  • 2023
  • In: Physical Review B. - 2469-9950. ; 108:7
  • Journal article (peer-reviewed)abstract
    • Rare Earth (RE) ion doped nanomaterials are promising candidates for a range of quantum technology applications. Among RE ions, the so-called Kramers' ions possess spin transitions in the GHz range at low magnetic fields, which allows for high-bandwidth multimode quantum storage, fast qubit operations as well as interfacing with superconducting circuits. They also present relevant optical transitions in the infrared. In particular, Er3+ has an optical transition in the telecom band, while Nd3+ presents a high-emission-rate transition close to 890 nm. In this paper, we measure spectroscopic properties that are of relevance to using these materials in quantum technology applications. We find the inhomogeneous linewidth to be 10.7 GHz for Er3+ and 8.2 GHz for Nd3+, and the excited state lifetime T1 to be 13.68 ms for Er3+ and 540μs for Nd3+. We study the dependence of homogeneous linewidth on temperature for both samples, with the narrowest linewidth being 379 kHz (T2=839 ns) for Er3+ measured at 3 K, and 62 kHz (T2=5.14μs) for Nd3+ measured at 1.6 K. Further, we investigate time-dependent homogeneous linewidth broadening due to spectral diffusion and the dependence of the homogeneous linewidth on magnetic field to get additional clarity of mechanisms that can influence the coherence time. In light of our results, we discuss two applications: single qubit-state readout and a Fourier-limited single photon source.
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6.
  • Amari, Atia, et al. (author)
  • Towards an efficient atomic frequency comb quantum memory
  • 2010
  • In: Journal of Luminescence. - : Elsevier BV. - 0022-2313. ; 130:9, s. 1579-1585
  • Conference paper (peer-reviewed)abstract
    • We present an efficient photon-echo experiment based on atomic frequency combs [Phys. Rev. A 79 (2009) 052329]. Echoes containing an energy of up to 35% of that of the input pulse are observed in a Pr3+ -doped Y2SiO5 crystal. This material allows for the precise spectral holeburning needed to make a sharp and highly absorbing comb structure. We compare our results with a simple theoretical model with satisfactory agreement. Our results show that atomic frequency combs has the potential for high-efficiency storage of single photons as required in future long-distance communication based on quantum repeaters. (c) 2010 Elsevier B.V. All rights reserved.
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7.
  • Andersson-Engels, Stefan, et al. (author)
  • Deep-tissue optical imaging and photoactivation activities at biophotonics@tyndall
  • 2016
  • In: Frontiers in Optics, FiO 2016. - 2162-2701. - 9781943580194
  • Conference paper (peer-reviewed)abstract
    • Activities for deep tissue imaging and photoactivation will be presented. Wihin Biophotonics@Tyndall projects based on upconverting nanoparticles and ultrasound optical tomography will be pursued. Data from collaborative research will be given.
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8.
  • Auer-Grumbach, Michaela, et al. (author)
  • Rare Variants in MME, Encoding Metalloprotease Neprilysin, Are Linked to Late-Onset Autosomal-Dominant Axonal Polyneuropathies
  • 2016
  • In: American Journal of Human Genetics. - : Elsevier BV. - 0002-9297 .- 1537-6605. ; 99:3, s. 607-623
  • Journal article (peer-reviewed)abstract
    • Axonal polyneuropathies are a frequent cause of progressive disability in the elderly. Common etiologies comprise diabetes mellitus, paraproteinaemia, and inflammatory disorders, but often the underlying causes remain elusive. Late-onset axonal Charcot-Marie-Tooth neuropathy (CMT2) is an autosomal-dominantly inherited condition that manifests in the second half of life and is genetically largely unexplained. We assumed age-dependent penetrance of mutations in a so far unknown gene causing late-onset CMT2. We screened 51 index case subjects with late-onset CMT2 for mutations by whole-exome (WES) and Sanger sequencing and subsequently queried WES repositories for further case subjects carrying mutations in the identified candidate gene. We studied nerve pathology and tissue levels and function of the abnormal protein in order to explore consequences of the mutations. Altogether, we observed heterozygous rare loss-of-function and missense mutations in MME encoding the metalloprotease neprilysin in 19 index case subjects diagnosed with axonal polyneuropathies or neurodegenerative conditions involving the peripheral nervous system. MME mutations segregated in an autosomal-dominant fashion with age-related incomplete penetrance and some affected individuals were isolated case subjects. We also found that MME mutations resulted in strongly decreased tissue availability of neprilysin and impaired enzymatic activity. Although neprilysin is known to degrade beta-amyloid, we observed no increased amyloid deposition or increased incidence of dementia in individuals with MME mutations. Detection of MME mutations is expected to increase the diagnostic yield in late-onset polyneuropathies, and it will be tempting to explore whether substances that can elevate neprilysin activity could be a rational option for treatment.
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9.
  • Ballantyne, Kaye N., et al. (author)
  • Toward Male Individualization with Rapidly Mutating Y-Chromosomal Short Tandem Repeats
  • 2014
  • In: Human Mutation. - : John Wiley & Sons. - 1059-7794 .- 1098-1004. ; 35:8, s. 1021-1032
  • Journal article (peer-reviewed)abstract
    • Relevant for various areas of human genetics, Y-chromosomal short tandem repeats (Y-STRs) are commonly used for testing close paternal relationships among individuals and populations, and for male lineage identification. However, even the widely used 17-loci Yfiler set cannot resolve individuals and populations completely. Here, 52 centers generated quality-controlled data of 13 rapidly mutating (RM) Y-STRs in 14,644 related and unrelated males from 111 worldwide populations. Strikingly, greater than99% of the 12,272 unrelated males were completely individualized. Haplotype diversity was extremely high (global: 0.9999985, regional: 0.99836-0.9999988). Haplotype sharing between populations was almost absent except for six (0.05%) of the 12,156 haplotypes. Haplotype sharing within populations was generally rare (0.8% nonunique haplotypes), significantly lower in urban (0.9%) than rural (2.1%) and highest in endogamous groups (14.3%). Analysis of molecular variance revealed 99.98% of variation within populations, 0.018% among populations within groups, and 0.002% among groups. Of the 2,372 newly and 156 previously typed male relative pairs, 29% were differentiated including 27% of the 2,378 father-son pairs. Relative to Yfiler, haplotype diversity was increased in 86% of the populations tested and overall male relative differentiation was raised by 23.5%. Our study demonstrates the value of RMY-STRs in identifying and separating unrelated and related males and provides a reference database.
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10.
  • Bartholomew, John G., et al. (author)
  • High-resolution spectroscopic techniques for studying rare-earth ions in nanoparticles
  • 2023
  • In: Journal of Luminescence. - : Elsevier BV. - 0022-2313. ; 257
  • Journal article (peer-reviewed)abstract
    • Rare-earth doped nanoparticles can exhibit narrow optical and spin linewidths at low temperatures. These outstanding properties for nanomaterials make them attractive for quantum technologies based on optically addressable spins such as quantum memories and computers. Although accurate linewidth measurements have been reported using, for example, spectral hole burning or photon echo techniques, so far they have been mostly restricted to large ensembles of particles. Being able to extend linewidths measurements to few and single particles is particularly important in view of their integration in nanophotonic devices. In this paper, we present techniques for determining inhomogeneous and homogeneous linewidths of small ensembles of rare-earth ions in doped nanoparticles with high signal-to-noise ratios for convenient integration times. Using these techniques we have observed property variations for particles from the same synthesis, a first step towards their optimization for applications in quantum technologies.
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11.
  • Bengtsson, Alexander, et al. (author)
  • Characterization and modeling of acousto-optic signal strengths in highly scattering media
  • 2019
  • In: Biomedical Optics Express. - 2156-7085. ; 10:11, s. 5565-5584
  • Journal article (peer-reviewed)abstract
    • Ultrasound optical tomography (UOT) is an imaging technique based on the acousto-optic effect that can perform optical imaging with ultrasound resolution inside turbid media, and is thus interesting for biomedical applications, e.g. for assessing tissue blood oxygenation. In this paper, we present near background free measurements of UOT signal strengths using slow light filter signal detection. We carefully analyze each part of our experimental setup and match measured signal strengths with calculations based on diffusion theory. This agreement between experiment and theory allows us to assert the deep tissue imaging potential of similar to 5 cm for UOT of real human tissues predicted by previous theoretical studies [Biomed. Opt. Express 8, 4523 (2017)] with greater confidence, and indicate that future theoretical analysis of optimized UOT systems can be expected to be reliable. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
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12.
  • Bondza, Saskia, et al. (author)
  • A simple experimental method for measuring the thermal sensitivity of single-mode fibers
  • 2020
  • In: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 91:10
  • Journal article (peer-reviewed)abstract
    • We present a simple technique to experimentally determine the optical-path length change with temperature for optical single-mode fibers. Standard single-mode fibers act as natural low-finesse cavities, with the Fresnel reflection of the straight cleaved surfaces being ∼3%, for the laser light coupled to them. By measuring the intensity variations due to interference of light reflected from the fiber front and end surfaces, while ramping the ambient temperature, the thermal sensitivity of the optical-path length of the fiber can be derived. Light was generated by a narrow linewidth, low drift laser. With our fairly short test fibers, we found that it was possible to reach a relative precision of the temperature sensitivity, compared to a reference fiber, on the 0.4%-2% scale and an absolute precision of 2%-5%, with the potential to improve both by an order of magnitude. The results for single-acrylate, dual-acrylate, and copper- and aluminum-coated fibers are presented. Values are compared with analytic models and results from a finite element method simulation. With the aid of these measurements, a simple fiber-interferometer, which is insensitive to thermal drifts, could be constructed.
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13.
  • Brockmann, Sarah J., et al. (author)
  • CHCHD10 mutations p.R15L and p.G66V cause motoneuron disease by haploinsufficiency
  • 2018
  • In: Human Molecular Genetics. - : Oxford University Press. - 0964-6906 .- 1460-2083. ; 27:4, s. 706-715
  • Journal article (peer-reviewed)abstract
    • Mutations in the mitochondrially located protein CHCHD10 cause motoneuron disease by an unknown mechanism. In this study, we investigate the mutations p. R15L and p. G66V in comparison to wild-type CHCHD10 and the non-pathogenic variant p. P34S in vitro, in patient cells as well as in the vertebrate in vivo model zebrafish. We demonstrate a reduction of CHCHD10 protein levels in p. R15L and p. G66V mutant patient cells to approximately 50%. Quantitative real-time PCR revealed that expression of CHCHD10 p. R15L, but not of CHCHD10 p. G66V, is already abrogated at the mRNA level. Altered secondary structure and rapid protein degradation are observed with regard to the CHCHD10 p. G66V mutant. In contrast, no significant differences in expression, degradation rate or secondary structure of non-pathogenic CHCHD10 p. P34S are detected when compared with wild-type protein. Knockdown of CHCHD10 expression in zebrafish to about 50% causes motoneuron pathology, abnormal myofibrillar structure and motility deficits in vivo. Thus, our data show that the CHCHD10 mutations p. R15L and p. G66V cause motoneuron disease primarily based on haploinsufficiency of CHCHD10.
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14.
  • Bruno, Raphael Romano, et al. (author)
  • Management and outcomes in critically ill nonagenarian versus octogenarian patients
  • 2021
  • In: BMC Geriatrics. - : BMC. - 1471-2318. ; 21:1
  • Journal article (peer-reviewed)abstract
    • Background: Intensive care unit (ICU) patients age 90 years or older represent a growing subgroup and place a huge financial burden on health care resources despite the benefit being unclear. This leads to ethical problems. The present investigation assessed the differences in outcome between nonagenarian and octogenarian ICU patients. Methods: We included 7900 acutely admitted older critically ill patients from two large, multinational studies. The primary outcome was 30-day-mortality, and the secondary outcome was ICU-mortality. Baseline characteristics consisted of frailty assessed by the Clinical Frailty Scale (CFS), ICU-management, and outcomes were compared between octogenarian (80-89.9 years) and nonagenarian (>= 90 years) patients. We used multilevel logistic regression to evaluate differences between octogenarians and nonagenarians. Results: The nonagenarians were 10% of the entire cohort. They experienced a higher percentage of frailty (58% vs 42%; p < 0.001), but lower SOFA scores at admission (6 +/- 5 vs. 7 +/- 6; p < 0.001). ICU-management strategies were different. Octogenarians required higher rates of organ support and nonagenarians received higher rates of life-sustaining treatment limitations (40% vs. 33%; p < 0.001). ICU mortality was comparable (27% vs. 27%; p = 0.973) but a higher 30-day-mortality (45% vs. 40%; p = 0.029) was seen in the nonagenarians. After multivariable adjustment nonagenarians had no significantly increased risk for 30-day-mortality (aOR 1.25 (95% CI 0.90-1.74; p = 0.19)). Conclusion: After adjustment for confounders, nonagenarians demonstrated no higher 30-day mortality than octogenarian patients. In this study, being age 90 years or more is no particular risk factor for an adverse outcome. This should be considered- together with illness severity and pre-existing functional capacity - to effectively guide triage decisions.
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15.
  • Chaitanya, Lakshmi, et al. (author)
  • Collaborative EDNAP exercise on the IrisPlex system for DNA based prediction of human eye colour
  • 2014
  • In: Forensic Science International. - : Elsevier. - 1872-4973 .- 1878-0326. ; 11, s. 241-251
  • Journal article (peer-reviewed)abstract
    • The IrisPlex system is a DNA-based test system for the prediction of human eye colour from biological samples and consists of a single forensically validated multiplex genotyping assay together with a statistical prediction model that is based on genotypes and phenotypes from thousands of individuals. IrisPlex predicts blue and brown human eye colour with, on average, >94% precision accuracy using six of the currently most eye colour informative single nucleotide polymorphisms (HERC2 rs12913832, OCA2 rs1800407, SLC24A4 rs12896399, SLC45A2 (MATP) rs16891982, TYR rs1393350, and IRF4 rs12203592) according to a previous study, while the accuracy in predicting non-blue and non-brown eye colours is considerably lower. In an effort to vigorously assess the IrisPlex system at the international level, testing was performed by 21 laboratories in the context of a collaborative exercise divided into three tasks and organised by the European DNA Profiling (EDNAP) Group of the International Society of Forensic Genetics (ISFG). Task 1 involved the assessment of 10 blood and saliva samples provided on FTA cards by the organising laboratory together with eye colour phenotypes; 99.4% of the genotypes were correctly reported and 99% of the eye colour phenotypes were correctly predicted. Task 2 involved the assessment of 5 DNA samples extracted by the host laboratory from simulated casework samples, artificially degraded, and provided to the participants in varying DNA concentrations. For this task, 98.7% of the genotypes were correctly determined and 96.2% of eye colour phenotypes were correctly inferred. For Tasks 1 and 2 together, 99.2% (1875) of the 1890 genotypes were correctly generated and of the 15 (0.8%) incorrect genotype calls, only 2 (0.1%) resulted in incorrect eye colour phenotypes. The voluntary Task 3 involved participants choosing their own test subjects for IrisPlex genotyping and eye colour phenotype inference, while eye photographs were provided to the organising laboratory and judged; 96% of the eye colour phenotypes were inferred correctly across 100 samples and 19 laboratories. The high success rates in genotyping and eye colour phenotyping clearly demonstrate the reproducibility and the robustness of the IrisPlex assay as well as the accuracy of the IrisPlex model to predict blue and brown eye colour from DNA. Additionally, this study demonstrates the ease with which the IrisPlex system is implementable and applicable across forensic laboratories around the world with varying pre-existing experiences.
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16.
  • Fronczek, Jakub, et al. (author)
  • Relationship between the Clinical Frailty Scale and short-term mortality in patients ≥ 80 years old acutely admitted to the ICU : a prospective cohort study
  • 2021
  • In: Critical Care. - : BioMed Central (BMC). - 1364-8535 .- 1466-609X. ; 25:1
  • Journal article (peer-reviewed)abstract
    • BACKGROUND: The Clinical Frailty Scale (CFS) is frequently used to measure frailty in critically ill adults. There is wide variation in the approach to analysing the relationship between the CFS score and mortality after admission to the ICU. This study aimed to evaluate the influence of modelling approach on the association between the CFS score and short-term mortality and quantify the prognostic value of frailty in this context.METHODS: We analysed data from two multicentre prospective cohort studies which enrolled intensive care unit patients ≥ 80 years old in 26 countries. The primary outcome was mortality within 30-days from admission to the ICU. Logistic regression models for both ICU and 30-day mortality included the CFS score as either a categorical, continuous or dichotomous variable and were adjusted for patient's age, sex, reason for admission to the ICU, and admission Sequential Organ Failure Assessment score.RESULTS: The median age in the sample of 7487 consecutive patients was 84 years (IQR 81-87). The highest fraction of new prognostic information from frailty in the context of 30-day mortality was observed when the CFS score was treated as either a categorical variable using all original levels of frailty or a nonlinear continuous variable and was equal to 9% using these modelling approaches (p < 0.001). The relationship between the CFS score and mortality was nonlinear (p < 0.01).CONCLUSION: Knowledge about a patient's frailty status adds a substantial amount of new prognostic information at the moment of admission to the ICU. Arbitrary simplification of the CFS score into fewer groups than originally intended leads to a loss of information and should be avoided. Trial registration NCT03134807 (VIP1), NCT03370692 (VIP2).
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17.
  • Fronczek, Jakub, et al. (author)
  • Short-term mortality or patients >= 80 years old admitted to European intensive care units: an international observational study
  • 2022
  • In: British Journal of Anaesthesia. - : ELSEVIER SCI LTD. - 0007-0912 .- 1471-6771. ; 129:1, s. 58-66
  • Journal article (peer-reviewed)abstract
    • Background: Limited evidence suggests variation in mortality of older critically ill adults across Europe. We aimed to investigate regional differences in mortality among very old ICU patients. Methods: Multilevel analysis of two international prospective cohort studies. We included patients >= 80 yr old from 322 ICUs located in 16 European countries. The primary outcome was mortality within 30 days from admission to the ICU. Results are presented as n (%) with 95% confidence intervals and odds ratios (ORs). Results: Of 8457 patients, 2944 (36.9% [35.9-38.0%]) died within 30 days. Crude mortality rates varied widely between participating countries (from 10.1% [6.4-15.6%] to 45.1% [41.1-49.2%] in the ICU and from 21.3% [16.3-28.9%] to 55.3% [51.1-59.5%] within 30 days). After adjustment for confounding variables, the variation in 30-day mortality between countries was substantially smaller than between ICUs (median OR 1.14 vs 1.58). Healthcare expenditure per capita (OR=0.84 per $1000 [0.75-0.94]) and social health insurance framework (OR=1.43 [1.01-2.01]) were associated with ICU mortality, but the direction and magnitude of these relationships was uncertain in 30-day follow-up. Volume of admissions was associated with lower mortality both in the ICU (OR=0.81 per 1000 annual ICU admissions [0.71-0.94]) and in 30-day follow-up (OR=0.86 [0.76-0.97]). Conclusion: The apparent variation in short-term mortality rates of older adults hospitalised in ICUs across Europe can be largely attributed to differences in the clinical profile of patients admitted. The volume-outcome relationship identified in this population requires further investigation.
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18.
  • Goldner, Ph., et al. (author)
  • Long coherence lifetime and electromagnetically induced transparency in a highly-spin-concentrated solid
  • 2009
  • In: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 79:3
  • Journal article (peer-reviewed)abstract
    • We have studied a rare-earth-doped crystal, Pr3+:La-2(WO4)(3), which exhibits a high magnetic-moment density. Although the latter favors rare-earth dephasing, a nuclear-spin coherence lifetime of 250 mu s has been observed, as well as electromagnetically induced transparency (EIT). This suggests that a broad range of materials could be considered for quantum information applications such as quantum memories for light, where solids are especially attractive. Absorption and dispersion curves are independently in very good agreement with EIT theory. Fano-like profiles have also been observed.
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19.
  • González-Castaño, Miriam, et al. (author)
  • 3D-printed structured catalysts for CO 2 methanation reaction: Advancing of gyroid-based geometries
  • 2022
  • In: Energy Conversion and Management. - : Elsevier BV. - 0196-8904. ; 258
  • Research review (peer-reviewed)abstract
    • This work investigates the CO2 methanation rate of structured catalysts by tuning the geometry of 3D-printed metal Fluid Guiding Elements (FGEs) structures based on periodically variable pseudo-gyroid geometries. The enhanced performance showed by the structured catalytic systems is mostly associated with the capability of the FGEs substrate geometries for efficient heat usages. Thus, variations on the channels diameter resulted in ca. 25% greater CO2 conversions values at intermediate temperature ranges. The highest void fraction evidenced in the best performing catalyst (3D-1) favored the radial heat transfer and resulted in significantly enhanced catalytic activity, achieving close to equilibrium (75%) conversions at 400 °C and 120 mL/min. For the 3D-1 catalyst, a mathematical model based on an experimental design was developed thus enabling the estimation of its behavior as a function of temperature, spatial velocity, hydrogen to carbon dioxide (H2/CO2) ratio, and inlet CO2 concentration. Its optimal operating conditions were established under 3 different scenarios: 1) no restrictions, 2) minimum H2:CO2 ratios, and 3) minimum temperatures and H2/CO2 ratio. For instance, for the lattest scenario, the best CO2 methanation conditions require operating at 431 °C, 200 mL/min, H2/CO2 = 3 M ratio, and inlet CO2 concentration = 10 %.
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20.
  • Guillot-Noel, O., et al. (author)
  • Hyperfine structure and hyperfine coherent properties of praseodymium in single-crystalline La-2(WO4)(3) by hole-burning and photon-echo techniques
  • 2009
  • In: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121. ; 79:15
  • Journal article (peer-reviewed)abstract
    • We studied the hyperfine structure and hyperfine coherent properties of the H-3(4)(0)-> D-1(2)(0) transition of Pr3+ ions in a tungstate single crystal La-2(WO4)(3) by hole-burning and photon-echo techniques. This work is motivated by the search of an efficient three level Lambda system in this new compound with which we could build up a quantum memory. By nonconventional hole-burning experiments, the ordering of the hyperfine splittings in the H-3(4)(0) ground state and in the D-1(2)(0) excited state is obtained. The hyperfine splittings are thus ordered: 24.6 and 14.9 MHz for the H-3(4)(0) level and 5.0 and 7.3 MHz for the D-1(2)(0) level. The relative and absolute transition strengths of individual hyperfine transitions are determined by comparing absorption strengths and by measuring the Rabi flopping frequency as the transition is coherently driven. Free induction and Raman echo decays give inhomogeneous and homogeneous hyperfine linewidths of 57 +/- 2 and 1.25 +/- 0.1 kHz, respectively.
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21.
  • Gunther, Jacqueline, et al. (author)
  • Deep tissue imaging with acousto-optical tomography and spectral hole burning with slow light effect : A theoretical study
  • 2018
  • In: Journal of Biomedical Optics. - 1083-3668. ; 23:7
  • Journal article (peer-reviewed)abstract
    • Biological tissue is a highly scattering medium that prevents deep imaging of light. For medical applications, optical imaging offers a molecular sensitivity that would be beneficial for diagnosing and monitoring of diseases. Acousto-optical tomography has the molecular sensitivity of optical imaging with the resolution of ultrasound and has the potential for deep tissue imaging. Here, we present a theoretical study of a system that combines acousto-optical tomography and slow light spectral filters created using spectral hole burning methods. Using Monte Carlo simulations, a model to obtain the contrast-to-noise ratio (CNR) deep in biological tissue was developed. The simulations show a CNR > 1 for imaging depths of ∼5 cm in a reflection mode setup, as well as, imaging through ∼12 cm in transmission mode setups. These results are promising and form the basis for future experimental studies.
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22.
  • Gunther, Jacqueline, et al. (author)
  • Theoretical study of combined acousto-optical tomography and slow light filters
  • 2018
  • In: Optical Tomography and Spectroscopy, OTS 2018. - 9781557528209 ; Part F90-OTS 2018
  • Conference paper (peer-reviewed)abstract
    • Monte Carlo simulations were used to determine the contrast-to-noise ratio of acoustooptical tomographic imaging with slow light filters versus possible imaging depth. Both reflection and transmission setups were considered. The theoretical model showed that imaging through 12 cm of breast tissue could be plausible.
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23.
  • Hagström, Åsa, et al. (author)
  • Subcellular localization of the fatty acyl reductase involved in pheromone biosynthesis in the tobacco budworm, Heliothis virescens (Noctuidae: Lepidoptera)
  • 2013
  • In: Insect Biochemistry and Molecular Biology. - : Elsevier BV. - 1879-0240 .- 0965-1748. ; 43:6, s. 510-521
  • Journal article (peer-reviewed)abstract
    • Sex pheromone components are produced in specialized glands of female moths via well-characterized biosynthetic pathways, where a Fatty Acyl Reductase (FAR) is often essential for producing the specific ratio of the different pheromone components. The subcellular localization and membrane topology of FARs is important for understanding how pheromones are synthesized and exported to the exterior for release. We investigated the subcellular localization of HvFAR from the noctuid moth Heliothis virescens by producing recombinant fusion proteins with green fluorescent protein (GFP) in yeast. A C-terminally tagged construct was localized to the endoplasmic reticulum (ER) and retained full reductive activity on a broad range of saturated and unsaturated fatty acyl precursors. In contrast, an N-terminally-tagged construct was poorly expressed in the cytoplasm and was not enzymatically active, indicating that HvFAR requires a free N-terminal for both proper targeting and catalytic activity. A series of truncations of the N-and C-termini of HvFAR was conducted based on in silico-predicted hydrophobic domains and transmembrane regions. The N-terminally truncated protein was found in the cytoplasm and did not retain activity, emphasizing the importance of the N-terminal for FAR function. In addition, the orientation in the membrane of the C-terminus-tagged HvFAR-GFP construct was analyzed using a fluorescence protease protection (FPP) assay, implying that the C-terminal of HvFAR is orientated towards the cytoplasm. These results, together with previous data on the localization of desaturases, confirm the importance of the ER as a subcellular site of pheromone production.
  •  
24.
  • Hastings-Simon, S R, et al. (author)
  • Spectral hole-burning spectroscopy in Nd3+: YVO4
  • 2008
  • In: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121. ; 77:12
  • Journal article (peer-reviewed)abstract
    • We present spectral hole-burning measurements on the 879 nm, I-4(9/2) -> F-4(3/2) transition in Nd3+ : YVO4. We observe antiholes in the spectrum along with long lived spectral holes, which demonstrates optical pumping between the ground state Zeeman levels. The spectral holes are narrow (homogeneous linewidth of 63 kHz) at 2.1 K with a 300 mT applied magnetic field. We also perform preliminary spectral tailoring in this material by creating a 40 MHz wide transmission window in the inhomogeneous absorption. These results show the potential of the Zeeman levels in Nd doped materials to be used for spectral tailoring for quantum and classical information processing.
  •  
25.
  • Horvath, Sebastian P., et al. (author)
  • Noise-free on-demand atomic frequency comb quantum memory
  • 2021
  • In: Physical Review Research. - 2643-1564. ; 3:2
  • Journal article (peer-reviewed)abstract
    • We present an extension of the atomic frequency comb protocol that utilizes the Stark effect to perform noise-free, on-demand, control. An experimental realization of this protocol was implemented in the Pr3+:Y2SiO5 solid-state system, and a recall efficiency of 38% for a 0.8 μs storage time was achieved. Experiments were performed with both bright pulses as well as weak-coherent states, the latter achieving a signal-to-noise ratio of 570±120 using input pulses with an average photon number of ∼0.1. The principal limitation for a longer storage time was found to be the minimum peak width attainable for Pr3+:Y2SiO5. We employ an adaptation of an established atomic frequency comb model to investigate an on-demand, wide-bandwidth, memory based on Eu3+:Y2SiO5. From this, we determine that a storage time as long as 100 μs may be practical even without recourse to spin-wave storage.
  •  
26.
  •  
27.
  • Jin, Hua, et al. (author)
  • Ionically interacting nanoclay and nanofibrillated cellulose lead to tough bulk nanocomposites in compression by forced self-assembly
  • 2013
  • In: Journal of Materials Chemistry B. - : Royal Society of Chemistry (RSC). - 2050-750X .- 2050-7518. ; 1:6, s. 835-840
  • Journal article (peer-reviewed)abstract
    • Several approaches have recently been shown for self-assembled biomimetic composite films, aiming at combinations of high toughness, strength, and stiffness. However, it remains challenging to achieve high toughness using simple processes especially for bulk materials. We demonstrate that ionically interacting cationic native nanofibrillated cellulose (C-NFC) and anionic nanoclay, i.e. montmorillonite (MTM), allow local self-assemblies by a simple centrifugation process to achieve 3D bulk materials. The composite with MTM/C-NFC of 63/37 w/w has a high compressive strain to failure of 37% with distinct plastic deformation behaviour, a high work to fracture of 23.1 MJ m(-3), and a relatively high compression strength of 76 MPa. Unlike the conventionally used sequential deposition methods to achieve well-defined layers for the oppositely charged units as limited to films, the present one-step method allows quick formation of bulk materials and leads to local self-assemblies, however, having a considerable amount of nanovoids and defects between them. We suggest that the nanovoids and defects promote the plastic deformation and toughness. Considering the simple preparation method and bio-based origin of NFC, we expect that the present tough bulk nanocomposites in compression have potential in applications for sustainable and environmentally friendly materials in construction and transportation.
  •  
28.
  •  
29.
  • Johansson, Mats, 1958-, et al. (author)
  • Positive end-expiratory pressure affects regional redistribution of ventilation differently in prone and supine sheep
  • 2004
  • In: Critical Care Medicine. - 0090-3493 .- 1530-0293. ; 32:10, s. 2039-2044
  • Journal article (peer-reviewed)abstract
    • Objective: To examine interactions between positive end-expiratory pressure (PEEP) and posture on regional distribution of ventilation and to compare measurements of regional ventilation with two aerosols: a wet fluorescent microsphere aerosol (FMS, median mass aerodynamic diameter 1.1 μm) and a dry 99mTc-labeled carbon particle aerosol (Technegas, TG, median mass aerodynamic diameter ≈0.1 μm). Design: Experimental study. Setting. Academic laboratory. Subjects: Anesthetized and mechanically ventilated sheep (n = 16). Interventions: Four conditions were studied: prone or supine posture with of without 10 cm H2O PEEP. Measurements and Main results: Comparisons of FMS and TG were made in five animals. The median correlation coefficient of the two ventilation tracers was .95 (range, .91-.96). The mean ventilation per unit weight of dry lung for horizontal planes was almost identical whether measured with TG or FMS. The distribution of ventilation was assessed by analyzing deposition of aerosol in about 1,000 lung regions per animal. Distribution of ventilation down the vertical axis was linear in prone (the slope indicated a dorsal-to-ventral three-fold difference in ventilation) but unimodal in supine animals with the mode in the center of the lung. Redistribution of ventilation with 10 PEEP differed between posture, shifting the mode in supine toward dependent lung regions while eliminating the dorsal-to-ventral gradient in prone. The regional heterogeneity in ventilation was greater in supine sheep at both levels of PEEP, and this was due mostly to greater isogravitational heterogeneity in supine than in prone position. Conclusions: The wet fluorescent microsphere aerosol was as reliable as Technegas for high-resolution measurements of regional ventilation. The markedly different effects of 10 PEEP in supine and prone sheep may have important implications for gas exchange both in noninjured and injured lungs.
  •  
30.
  • Julsgaard, Brian, et al. (author)
  • Understanding laser stabilization using spectral hole burning
  • 2007
  • In: Optics Express. - 1094-4087. ; 15:18, s. 11444-11465
  • Journal article (peer-reviewed)abstract
    • There have recently been several studies of the performance of laser frequency stabilization using spectral holes in solids, instead of an external cavity, as a frequency reference. Here an analytical theory for Pound-Drever-Hall laser frequency stabilization using spectral hole-burning is developed. The interaction between the atomic medium and the phase modulated light is described using a linearized model of the Maxwell-Bloch equations. The interplay between the carrier and modulation sidebands reveals significant differences from the case of locking to a cavity. These include a different optimum modulation index, an optimum sample absorption, and the possibility to lock the laser in an inherent linear frequency drift mode. Spectral holes in solids can be permanent or transient. For the materials normally used, the dynamics and time scales of transient holes often depend on population relaxation processes between ground state hyperfine levels. These relaxation rates can be very different for different solid state materials. We demonstrate, using radio-frequency pumping, that the hyperfine population dynamics may be controlled and tailored to give optimum frequency stabilization performance. In this way also materials with initially non-optimum performance can be used for stabilization. The theoretical predictions regarding the inherent linear frequency drift is compared to experimental data from a dye laser stabilized to a spectral hole in a Pr3+: Y2SiO5 crystal. (C) 2007 Optical Society of America.
  •  
31.
  • Jung, Christian, et al. (author)
  • A comparison of very old patients admitted to intensive care unit after acute versus elective surgery or intervention
  • 2019
  • In: Journal of critical care. - : W B SAUNDERS CO-ELSEVIER INC. - 0883-9441 .- 1557-8615. ; 52, s. 141-148
  • Journal article (peer-reviewed)abstract
    • Background: We aimed to evaluate differences in outcome between patients admitted to intensive care unit (ICU) after elective versus acute surgery in a multinational cohort of very old patients (80 years; VIP). Predictors of mortality, with special emphasis on frailty, were assessed.Methods: In total, 5063 VIPs were induded in this analysis, 922 were admitted after elective surgery or intervention, 4141 acutely, with 402 after acute surgery. Differences were calculated using Mann-Whitney-U test and Wilcoxon test. Univariate and multivariable logistic regression were used to assess associations with mortality.Results: Compared patients admitted after acute surgery, patients admitted after elective surgery suffered less often from frailty as defined as CFS (28% vs 46%; p < 0.001), evidenced lower SOFA scores (4 +/- 5 vs 7 +/- 7; p < 0.001). Presence of frailty (CFS >4) was associated with significantly increased mortality both in elective surgery patients (7% vs 12%; p = 0.01), in acute surgery (7% vs 12%; p = 0.02).Conclusions: VIPs admitted to ICU after elective surgery evidenced favorable outcome over patients after acute surgery even after correction for relevant confounders. Frailty might be used to guide clinicians in risk stratification in both patients admitted after elective and acute surgery. 
  •  
32.
  • Karlsson, Jenny, et al. (author)
  • High-resolution transient and permanent spectral hole burning in Ce3+ : Y2SiO5 at liquid helium temperatures
  • 2016
  • In: Physical Review B. - 1098-0121. ; 93:22
  • Journal article (peer-reviewed)abstract
    • We perform hole burning with a low-drift stabilized laser within the zero phonon line of the 4f-5d transition in Ce3+:Y2SiO5 at 2 K. The narrowest spectral holes appear for small applied magnetic fields and are 6±4 MHz wide (FWHM). This puts an upper bound on the homogeneous linewidth of the transition to 3±2 MHz, which is close to lifetime limited. The spin level relaxation time is measured to 72±21 ms with a magnetic field of 10 mT. A slow permanent hole burning mechanism is observed. If the excitation frequency is not changed the fluorescence intensity is reduced by more than 50% after a couple of minutes of continuous excitation. The spectral hole created by the permanent hole burning has a width in the tens of MHz range, which indicates that a trapping mechanism occurs via the 5d state.
  •  
33.
  • Kattge, Jens, et al. (author)
  • TRY plant trait database - enhanced coverage and open access
  • 2020
  • In: Global Change Biology. - : Wiley-Blackwell. - 1354-1013 .- 1365-2486. ; 26:1, s. 119-188
  • Journal article (peer-reviewed)abstract
    • Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.
  •  
34.
  • Kinos, Adam, et al. (author)
  • Designing gate operations for single-ion quantum computing in rare-earth-ion-doped crystals
  • 2021
  • In: Physical Review A. - 2469-9926. ; 104:5
  • Journal article (peer-reviewed)abstract
    • Quantum computers based on rare-earth-ion-doped crystals show promising properties in terms of scalability and connectivity if single ions can be used as qubits. Through simulations, we investigate gate operations on such qubits. We discuss how gate and system parameters affect gate errors, the required frequency bandwidth per qubit, and the risk for instantaneous spectral diffusion (ISD). Furthermore, we examine how uncertainties in the system parameters affect the gate errors, and how precisely the system needs to be known. We find gate errors for arbitrary single-qubit gates of 2.1×10-4 when ISD is not considered and 3.4×10-4 when we take heed to minimize it. Additionally, we construct two-qubit gates with errors ranging from 5×10-4→3×10-3 over a broad range of dipole-dipole interaction strengths.
  •  
35.
  • Kinos, Adam, et al. (author)
  • High-connectivity quantum processor nodes using single-ion qubits in rare-earth-ion-doped crystals
  • 2022
  • In: Physical Review A. - 2469-9926. ; 105:3
  • Journal article (peer-reviewed)abstract
    • We present two protocols for constructing quantum processor nodes in randomly doped rare-earth-ion crystals and analyze their properties. By varying the doping concentration and the accessible laser tunability, the processor nodes can contain anywhere from only a few tens to almost 1000 qubits. Furthermore, the average number of qubits each qubit can interact with, denoted by the connectivity, can be partly tailored to lie between just a few and roughly 100. We also study how a limited tunability of the laser affects the results and conclude that a tuning range of 100 GHz limits the results to roughly 100 qubits with around 50 connections per qubit on average. In order to construct an even larger processor, the vision is that several of these quantum processor nodes should be connected to each other in a multinode architecture via, e.g., optical interfaces or flying qubits in the form of light. Our results are encouraging for establishing the rare-earth-ion-based systems as a quantum computing platform with strong potential and can serve to focus the efforts within the field.
  •  
36.
  • Kinos, Adam, et al. (author)
  • Microscopic treatment of instantaneous spectral diffusion and its effect on quantum gate fidelities in rare-earth-ion-doped crystals
  • 2022
  • In: Physical Review A. - 2469-9926. ; 105:3
  • Journal article (peer-reviewed)abstract
    • The effect of instantaneous spectral diffusion (ISD) on gate operations in rare-earth-ion-doped crystals is an important question to answer for the future of rare-earth quantum computing. Here we present a microscopic modeling that highlights the stochastic nature of the phenomenon and use it to investigate ISD errors on single-qubit gate operations. Furthermore, we present a method to estimate the total error from many different error sources by only studying subsystems containing one error source at a time. This allows us to estimate the total ISD error from all nonqubit dopants in the vicinity of a qubit. We conclude that optical pumping techniques must be used to empty the frequency regions around the qubit transitions from absorption (transmission windows) in order to suppress the ISD errors. Despite using such windows, there remains a roughly 0.3% risk that a qubit has an ISD error larger than the error from other sources. In those cases, the qubit can be discarded and its frequency channel can be reused by another qubit. However, in most cases the ISD errors are significantly smaller than other errors, thus opening up the possibility to perform noisy intermediate-scale quantum (NISQ) algorithms despite ISD being present.
  •  
37.
  • Kochumalayil, Joby Kochumalayil, et al. (author)
  • Nacre-Mimetic Clay/Xyloglucan Bionanocomposites : A Chemical Modification Route for Hygromechanical Performance at High Humidity
  • 2013
  • In: Biomacromolecules. - : American Chemical Society (ACS). - 1525-7797 .- 1526-4602. ; 14:11, s. 3842-3849
  • Journal article (peer-reviewed)abstract
    • Nacre-mimetic bionanocomposites of high montmorillonite (MTM) clay content, prepared from hydra. colloidal suspensions, suffer from reduced strength and stiffness at high relative humidity. We address this problem by chemical modification of xyloglucan in (XG)/MTM nacremimetic nanocomposites, by subjecting the XG to regioselective periodate oxidation of side chains to enable it to form covalent cross-links to hydroxyl groups in neighboring XG chains or to the MTM surface. The resulting materials are analyzed by FTIR spectroscopy, thermogravimetric analysis, carbohydrate analysis, calorimetry, X-ray diffraction, scanning electron microscopy, tensile tests, and oxygen barrier properties. We compare the resulting mechanical properties at low and high relative humidity. The periodate oxidation leads to a strong increase in modulus and strength of the materials. A modulus of 30 GPa for cross-linked composite at 50% relative humidity compared with 13.7 GPa for neat XG/MTM demonstrates that periodate oxidation of the XG side chains leads to crucially improved stress transfer at the XG/MTM interface, possibly through covalent bond formation. This enhanced interfacial adhesion and internal cross-linking of the matrix moreover preserves the mechanical properties at high humidity condition and leads to a Young's modulus of 21 GPa at 90%RH.
  •  
38.
  • Liu, Andong, et al. (author)
  • Clay Nanopaper with Tough Cellulose Nanofiber Matrix for Fire Retardancy and Gas Barrier Functions
  • 2011
  • In: Biomacromolecules. - : American Chemical Society. - 1525-7797 .- 1526-4602. ; 12:3, s. 633-641
  • Journal article (peer-reviewed)abstract
    • Nacre-mimicking hybrids of high inorganic content (> 50 wt %) tend to show low strain-to-failure. Therefore, we prepared clay nanopaper hybrid composite montmorillonite platelets in a continuous matrix of nanofibrillated cellulose (NFC) with the aim of harnessing the intrinsic toughness of fibrillar networks. Hydrocolloid mixtures were used in a filtration approach akin to paper processing. The resulting multilayered structure of the nanopaper was studied by FE-SEM, FTIR, and XRD. Uniaxial stress strain curves measured in tension and thermal analysis were carried out by DMTA and TGA. In addition, fire retardance and oxygen permeability characteristics were measured. The continuous NFC matrix is a new concept and provides unusual ductility to the nanocomposite, allowing inorganic contents as high as 90% by weight. Clay nanopaper extends the property range of cellulose nanopaper and is of interest in self-extinguishing composites and in oxygen barrier layers.
  •  
39.
  • Ludwig, Sebastian, et al. (author)
  • Transcatheter Mitral Valve Replacement versus Medical Therapy for Secondary Mitral Regurgitation: A Propensity Score-Matched Comparison.
  • 2023
  • In: Circulation. Cardiovascular interventions. - 1941-7632. ; 16:6
  • Journal article (peer-reviewed)abstract
    • Background: Transcatheter mitral valve replacement (TMVR) is an emerging therapeutic alternative for patients with secondary mitral regurgitation (MR). Outcomes of TMVR versus guideline-directed medical therapy (GDMT) have not been investigated for this population. This study aimed to compare clinical outcomes of patients with secondary MR undergoing TMVR versus GDMT alone. Methods: The CHOICE-MI registry included patients with MR undergoing TMVR using dedicated devices. Patients with MR etiologies other than secondary MR were excluded. Patients treated with GDMT alone were derived from the control arm of the COAPT trial. We compared outcomes between the TMVR and GDMT groups, using propensity score (PS)-matching to adjust for baseline differences. Results: After PS-matching, 97 patient pairs undergoing TMVR (72.9±8.7 years, 60.8% male, transapical access 91.8%) versus GDMT (73.1±11.0 years, 59.8% male) were compared. At 1 and 2 years, residual MR was ≤1+ in all patients of the TMVR group compared to 6.9% and 7.7%, respectively, in those receiving GDMT alone (both p<0.001). The 2-year rate of HF hospitalization was significantly lower in the TMVR group (32.8% vs. 54.4%, HR 0.59, 95% CI 0.35-0.99; p=0.04). Among survivors, a higher proportion of patients were in NYHA functional class I or II in the TMVR group at 1 year (78.2% vs. 59.7%, p=0.03) and at 2 years (77.8% vs. 53.2%, p=0.09). Two-year mortality was similar in the two groups (TMVR vs. GDMT, 36.8% vs. 40.8%, HR 1.01, 95% CI 0.62-1.64; p=0.98). Conclusions: In this observational comparison, over 2-year follow-up, TMVR using mostly transapical devices in patients with secondary MR was associated with significant reduction of MR, symptomatic improvement, less frequent hospitalizations for HF and similar mortality compared with GDMT.
  •  
40.
  • Martikainen, Lahja, et al. (author)
  • Deoxyguanosine Phosphate Mediated Sacrificial Bonds Promote Synergistic Mechanical Properties in Nacre-Mimetic Nanocomposites
  • 2013
  • In: Biomacromolecules. - : American Chemical Society (ACS). - 1525-7797 .- 1526-4602. ; 14:8, s. 2531-2535
  • Journal article (peer-reviewed)abstract
    • We show that functionalizing polymer-coated colloidal nanoplatelets with guanosine groups allows synergistic increase of mechanical properties in nacre-mimetic lamellar self-assemblies. Anionic montmorillonite (MTM) was first coated using cationic poly(diallyldimethylammonium chloride) (PDADMAC) to prepare core-shell colloidal platelets, and subsequently the remaining chloride counterions allowed exchange to functional anionic 2'-deoxyguanosine 5'-monophosphate (dGMP) counterions, containing hydrogen bonding donors and acceptors. The compositions were studied using elemental analysis, scanning and transmission electron microscopy, wide-angle X-ray scattering, and tensile testing. The lamellar spacing between the clays increases from 1.85 to 2.14 nm upon addition of the dGMP. Adding dGMP increases the elastic modulus, tensile strength, and strain 33.0%, 40.9%, and 5.6%, respectively, to 13.5 GPa, 67 MPa, and 1.24%, at 50% relative humidity. This leads to an improved toughness seen as a ca. 50% increase of the work-to-failure. This is noteworthy, as previously it has been observed that connecting the core-shell nanoclay platelets covalently or ionically leads to increase of the stiffness but to reduced strain. We suggest that the dynamic supramolecular bonds allow slippage and sacrificial bonds between the self-assembling nanoplatelets, thus promoting toughness, still providing dynamic interactions between the platelets.
  •  
41.
  • Papousek, Ilona, et al. (author)
  • Serotonin Transporter Genotype (5-HTTLPR) and Electrocortical Responses Indicating the Sensitivity to Negative Emotional Cues
  • 2013
  • In: Emotion. - : AMER PSYCHOLOGICAL ASSOC. - 1528-3542 .- 1931-1516. ; 13:6, s. 1173-1181
  • Journal article (peer-reviewed)abstract
    • Growing literature indicates that emotional reactivity and regulation are strongly linked to genetic modulation of serotonergic neurotransmission. However, until now, most studies have focused on the relationship between genotypic markers, in particular the serotonin transporter-linked polymorphic region (5-HTTLPR), and neural structures using MRI. The current study aimed to bridge the gap between the relevant MRI literature on the effects of the 5-HTTLPR genotype and the research tradition focusing on transient lateralized changes of electrocortical activity in the prefrontal cortex using electroencephalography (EEG). Lateral shifts of EEG alpha asymmetry in response to an aversive film consisting of scenes of real injury and death were assessed in healthy participants (n = 165). To evaluate the specificity of the 5-HTTLPR effect, participants were also tested for the COMT Val158Met polymorphism which is linked to dopamine inactivation. While viewing the film, individuals homozygous for the 5-HTTLPR short allele displayed a clear lateral shift of dorsolateral frontal activity to the right, which was virtually absent in participants carrying the long allele. The heightened electrocortical response to the aversive stimulation and its direction indicates a greater propensity of s/s homozygotes to experience withdrawal oriented affect in response to negative emotion cues in the environment. Moreover, together with previous research the findings support the notion of a link between the serotonergic system and self-regulation related to avoidance motivation, and a link between the dopaminergic system and self-regulation related to approach motivation.
  •  
42.
  • Rippe, Lars, et al. (author)
  • Experimental quantum-state tomography of a solid-state qubit
  • 2008
  • In: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 77:2, s. 5-022307
  • Journal article (peer-reviewed)abstract
    • Quantum-state tomography is used to characterize the state of an ensemble based qubit implemented through two hyperfine levels in Pr3+ ions, doped into a Y2SiO5 crystal. We experimentally verify that single-qubit rotation errors due to inhomogeneities of the ensemble can be suppressed using the Roos-Molmer dark-state scheme [Roos and Molmer, Phys. Rev. A 69, 022321 (2004)] Fidelities above > 90%, presumably limited by excited state decoherence, were achieved. Although not explicitly taken care of in the Roos-Molmer scheme, it appears that also decoherence due to inhomogeneous broadening on the hyperfine transition is largely suppressed.
  •  
43.
  • Rolander, Arvid, et al. (author)
  • Quantum error correction in the noisy intermediate-scale quantum regime for sequential quantum computing
  • 2022
  • In: Physical Review A. - 2469-9926. ; 105:6
  • Journal article (peer-reviewed)abstract
    • We use density-matrix simulations to study the performance of three distance three quantum error correction (QEC) codes in the context of the rare-earth (RE) ion-doped crystal platform for quantum computing. We analyze pseudothresholds for these codes when parallel operations are not available, and examine the behavior both with and without resting errors. In RE systems, resting errors can be mitigated by extending the system's ground-state coherence time. For the codes we study, we find that if the ground-state coherence time is roughly 100 times larger than the excited-state coherence time, resting errors become small enough to be negligible compared to other error sources. This leads us to the conclusion that beneficial QEC could be achieved in the RE system with the expected gate fidelities available in the noisy intermediate-scale quantum regime. However, for codes using more qubits and operations, a factor of more than 100 would be required. Furthermore, we investigate how often QEC should be performed in a circuit. We find that for early experiments in RE systems, the minimal 5,1,3 would be most suitable as it has a high threshold error and uses few qubits. However, when more qubits are available the 9,1,3 surface code might be a better option due to its higher circuit performance. Our findings are important for steering experiments to an efficient path for realizing beneficial quantum error correcting codes in early RE systems where resources are limited.
  •  
44.
  • Sabooni, Mahmood, et al. (author)
  • Storage and Recall of Weak Coherent Optical Pulses with an Efficiency of 25%
  • 2010
  • In: Physical Review Letters. - 1079-7114. ; 105:6
  • Journal article (peer-reviewed)abstract
    • We demonstrate experimentally an efficient coherent rephasing scheme for the storage and recall of weak coherent light pulses in an inhomogeneously broadened optical transition in a Pr3+: YSO crystal at 2.1 K. Precise optical pumping using a frequency stable (approximate to 1 kHz linewidth) laser is employed to create a highly controllable atomic frequency comb structure. We report single photon level storage and retrieval efficiencies of 25%, based on coherent photon-echo-type reemission in the forward direction. The high efficiency is mainly a product of our highly controllable and precise ensemble-shaping technique. The coherence property of the quantum memory is proved through interference between a super-Gaussian pulse and the emitted echo.
  •  
45.
  • Serrano, Diana, et al. (author)
  • Impact of the ion-ion energy transfer on quantum computing schemes in rare-earth doped solids
  • 2014
  • In: Journal of Luminescence. - : Elsevier BV. - 0022-2313. ; 151, s. 93-99
  • Journal article (peer-reviewed)abstract
    • We analyze the Ce3+-Pr3+:Y2SiO5 emission spectra obtained under selective excitation of the two Ce3+ sites in Y2SiO5 and we show clear evidence of direct energy transfer from Ce3+ to Pr3+. Energy transfer microparameters were calculated from the experimental spectral overlap between the Ce3+ emission and the Pr3+ and Eu3+ absorptions from which, the transfer mechanisms Ce3+-> Pr3+ are concluded to be more efficient than the transfer mechanisms Ce3+-> Eu3+. The energy transfer processes demonstrated here are potentially detrimental for an efficient qubit readout, using Ce3+ as readout ion, as they lead to a quenching of the Ce3+ luminescence and can give rise to the unwanted change of Pr3+ and Eu3+ qubit states. The quantum computing readout scheme is based on permanent electric dipole interactions scaling as R-3, where R is the distance between the Ce3+ and the qubit ion. The non-radiative energy transfer processes also depend on the ion-ion distances, however as R-6. A discussion about the microscopic dopant distributions leading to an efficient single-ion readout quantum computing scheme is here presented. The likely existence of energy transfer paths between the qubits or, as in this case, between the readout ion and the qubit ions, has not been taken into account so far by the rare-earth based quantum computing approaches. The results of this study suggest the need to consider them in order to design realistic and efficient quantum computing schemes for rare-earth doped solids. (C) 2014 Elsevier B.V. All rights reserved.
  •  
46.
  • Serrano, Diana, et al. (author)
  • Satellite line mapping in Eu3+-Ce3+ and Pr3+-Ce3+ codoped Y2SiO5
  • 2016
  • In: Journal of Luminescence. - : Elsevier BV. - 0022-2313. ; 170, s. 102-107
  • Journal article (peer-reviewed)abstract
    • In this work we perform a high-resolution spectroscopic investigation of Eu3+-Ce3+ and Pr3+-Ce3+ codoped Y2SiO5 crystals. Satellite line spectra were recorded at low temperatures around the Eu3+:F-7(0) -> D-5(0) and the Pr3+:H-3(4) -> D-1(2) transitions. It is observed that the incorporation of Ce3+ as a codopant notably changes the Eu3+ and Pr3+ satellite line patterns. Satellite lines measured in singly doped Eu3+:Y2SiO5 were found at the same spectral positions in Eu3+-Ce3+ codoped crystals. These coincident lines were concluded to be due to pairs of Eu3+ ions. Extra satellite lines appeared in the codoped crystals, which were assigned to Ce3+ related structures such as Ce3+-Eu3+ pairs. The analysis of the Pr3+ satellite line spectra presents further challenges. Satellite lines associated to Pr3+ pairs show weaker intensity, presumably due to the efficient quenching of the Pr3+ D-1(2) emission through cross-relaxation paths (D-1(2) -> (1)G(4); H-3(4) -> F-3(4)). The investigation of the Eu3+ and Pr3+ satellite line patterns in Y2SiO5 is particularly interesting for their exploitation in rare-earth based quantum computation schemes. (C) 2015 Elsevier B.V. All rights reserved.
  •  
47.
  • Shi, Juanzi, et al. (author)
  • Photoluminescence Polarization of MAPbBr3 Perovskite Nanostructures. Can the Dielectric Contrast Effect Explain It?
  • 2022
  • In: ACS Photonics. - : American Chemical Society (ACS). - 2330-4022. ; 9:12, s. 3888-3898
  • Journal article (peer-reviewed)abstract
    • The dielectric contrast effect is usually evoked to explain anisotropy of optical properties of elongated nanoobjects, for example, semiconductor nanowires. We applied two-dimensional polarization imaging microscopy to measure the polarization of photoluminescence (PL) excitation and PL intensity of nanoaggregates of in-situ formed MAPbBr3perovskite nanoparticles in a stretched polymeric matrix. Scanning electron microscopy images of these objects were also acquired to characterize their sizes and shapes. We find that individual perovskite aggregates with sizes of 100-300 nm often possess a PL excitation polarization degree as high as 0.5-0.9, which is up to three times higher than the polarization degree of absorption predicted by the dielectric contrast effect. Small aggregates of nanoparticles possess an emission polarization degree substantially higher than that of excitation. Computer simulations of many possible scenarios show that the dielectric contrast alone cannot quantitatively explain the polarization properties of the studied objects. We propose energy transfer to localized emitting sites and the dependence of PL yield on excitation power density as possible factors strongly influencing the polarization properties of PL emission and PL excitation, respectively.
  •  
48.
  • Tehua Lu, Timothy, et al. (author)
  • An evaluation of the genetic-matched pair study design using genome-wide SNP data from the European population
  • 2009
  • In: European Journal of Human Genetics. - : Springer Science and Business Media LLC. - 1018-4813 .- 1476-5438. ; 17:7, s. 967-975
  • Journal article (peer-reviewed)abstract
    • Genetic matching potentially provides a means to alleviate the effects of incomplete Mendelian randomization in population-based gene-disease association studies. We therefore evaluated the genetic-matched pair study design on the basis of genome-wide SNP data (309 790 markers; Affymetrix GeneChip Human Mapping 500K Array) from 2457 individuals, sampled at 23 different recruitment sites across Europe. Using pair-wise identity-by-state (IBS) as a matching criterion, we tried to derive a subset of markers that would allow identification of the best overall matching (BOM) partner for a given individual, based on the IBS status for the subset alone. However, our results suggest that, by following this approach, the prediction accuracy is only notably improved by the first 20 markers selected, and increases proportionally to the marker number thereafter. Furthermore, in a considerable proportion of cases (76.0%), the BOM of a given individual, based on the complete marker set, came from a different recruitment site than the individual itself. A second marker set, specifically selected for ancestry sensitivity using singular value decomposition, performed even more poorly and was no more capable of predicting the BOM than randomly chosen subsets. This leads us to conclude that, at least in Europe, the utility of the genetic-matched pair study design depends critically on the availability of comprehensive genotype information for both cases and controls. European Journal of Human Genetics (2009) 17, 967-975; doi:10.1038/ejhg.2008.266; published online 21 January 2009
  •  
49.
  • Tillmar, Andreas, et al. (author)
  • DNA Commission of the International Society for Forensic Genetics ( ISFG): Guidelines on the use of X-STRs in kinship analysis
  • 2017
  • In: Forensic Science International. - : ELSEVIER IRELAND LTD. - 1872-4973 .- 1878-0326. ; 29, s. 269-275
  • Journal article (peer-reviewed)abstract
    • Forensic genetic laboratories perform an increasing amount of genetic analyses of the X chromosome, in particular to solve complex cases of kinship analysis. For some biological relationships X-chromosomal markers can be more informative than autosomal markers, and there are a large number of markers, methods and databases that have been described for forensic use. Due to their particular mode of inheritance, and their physical location on a single chromosome, some specific considerations are required when estimating the weight of evidence for X-chromosomal marker DNA data. The DNA Commission of the International Society for Forensic Genetics (ISFG) hereby presents guidelines and recommendations for the use of X-chromosomal markers in kinship analysis with a special focus on the biostatistical evaluation. Linkage and linkage disequilibrium (association of alleles) are of special importance for such evaluations and these concepts and the implications for likelihood calculations are described in more detail. Furthermore it is important to use appropriate computer software that accounts for linkage and linkage disequilibrium among loci, as well as for mutations. Even though some software exist, there is still a need for further improvement of dedicated software. (C) 2017 Elsevier B.V. All rights reserved.
  •  
50.
  • Walther, Andreas, et al. (author)
  • Analysis of the potential for non-invasive imaging of oxygenation at heart depth, using ultrasound optical tomography (UOT) or photo-acoustic tomography (PAT)
  • 2017
  • In: Biomedical Optics Express. - 2156-7085. ; 8:10, s. 4523-4536
  • Journal article (peer-reviewed)abstract
    • Despite the important medical implications, it is currently an open task to find optical non-invasive techniques that can image deep organs in humans. Addressing this, photo-acoustic tomography (PAT) has received a great deal of attention in the past decade, owing to favorable properties like high contrast and high spatial resolution. However, even with optimal components PAT cannot penetrate beyond a few centimeters, which still presents an important limitation of the technique. Here, we calculate the absorption contrast levels for PAT and for ultrasound optical tomography (UOT) and compare them to their relevant noise sources as a function of imaging depth. The results indicate that a new development in optical filters, based on rare-earth-ion crystals, can push the UOT technique significantly ahead of PAT. Such filters allow the contrastto- noise ratio for UOT to be up to three orders of magnitude better than for PAT at depths of a few cm into the tissue. It also translates into a significant increase of the image depth of UOT compared to PAT, enabling deep organs to be imaged in humans in real time. Furthermore, such spectral holeburning filters are not sensitive to speckle decorrelation from the tissue and can operate at nearly any angle of incident light, allowing good light collection. We theoretically demonstrate the improved performance in the medically important case of non-invasive optical imaging of the oxygenation level of the frontal part of the human myocardial tissue. Our results indicate that further studies on UOT are of interest and that the technique may have large impact on future directions of biomedical optics.
  •  
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