1. |
|
|
2. |
|
|
3. |
|
|
4. |
- Mozzachiodi, S., et al.
(author)
-
Aborting meiosis allows recombination in sterile diploid yeast hybrids
- 2021
-
In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 12:1
-
Journal article (peer-reviewed)abstract
- Hybrids are often considered evolutionary dead ends because they do not generate viable offspring. Here, the authors show that sterile yeast hybrids generate genetic diversity through meiotic-like recombination by aborting meiosis and return to asexual growth. Hybrids between diverged lineages contain novel genetic combinations but an impaired meiosis often makes them evolutionary dead ends. Here, we explore to what extent an aborted meiosis followed by a return-to-growth (RTG) promotes recombination across a panel of 20 Saccharomyces cerevisiae and S. paradoxus diploid hybrids with different genomic structures and levels of sterility. Genome analyses of 275 clones reveal that RTG promotes recombination and generates extensive regions of loss-of-heterozygosity in sterile hybrids with either a defective meiosis or a heavily rearranged karyotype, whereas RTG recombination is reduced by high sequence divergence between parental subgenomes. The RTG recombination preferentially arises in regions with low local heterozygosity and near meiotic recombination hotspots. The loss-of-heterozygosity has a profound impact on sexual and asexual fitness, and enables genetic mapping of phenotypic differences in sterile lineages where linkage analysis would fail. We propose that RTG gives sterile yeast hybrids access to a natural route for genome recombination and adaptation.
|
|
5. |
- Rees, R. M., et al.
(author)
-
Nitrous oxide emissions from European agriculture - an analysis of variability and drivers of emissions from field experiments
- 2013
-
In: Biogeosciences. - : Copernicus GmbH. - 1726-4170 .- 1726-4189. ; 10:4, s. 2671-2682
-
Journal article (peer-reviewed)abstract
- Nitrous oxide emissions from a network of agricultural experiments in Europe and Zimbabwe were used to explore the relative importance of site and management controls of emissions. At each site, a selection of management interventions were compared within replicated experimental designs in plot based experiments. Arable experiments were conducted at Beano in Italy, El Encin in Spain, Foulum in Denmark, Logården in Sweden, Maulde in Belgium, Paulinenaue in Germany, Harare in Zimbabwe and Tulloch in the UK. Grassland experiments were conducted at Crichton, Nafferton and Peaknaze in the UK, Gödöllö in Hungary, Rzecin in Poland, Zarnekow in Germany and Theix in France. Nitrous oxide emissions were measured at each site over a period of at least two years using static chambers. Emissions varied widely between sites and as a result of manipulation treatments. Average site emissions (throughout the study period) varied between 0.04 and 21.21 kg N2O-N ha−1 yr−1, with the largest fluxes and variability associated with the grassland sites. Total nitrogen addition was found to be the single most important determinant of emissions, accounting for 15% of the variance (using linear regression) in the data from the arable sites (p < 0.0001), and 77% in the grassland sites. The annual emissions from arable sites were significantly greater than those that would be predicted by IPCC default emission factors. Variability in N2O within sites that occurred as a result of manipulation treatments was greater than that resulting from site to site and year to year variation, highlighting the importance of management interventions in contributing to greenhouse gas mitigation.
|
|
6. |
|
|
7. |
- Harvey, B. P., et al.
(author)
-
Evolution of marine organisms under climate change at different levels of biological organisation
- 2014
-
In: Water. - : MDPI AG. - 2073-4441. ; 6:11, s. 3545-3574
-
Journal article (peer-reviewed)abstract
- Research to date has suggested that both individual marine species and ecologicalprocesses are expected to exhibit diverse responses to the environmental effects of climatechange. Evolutionary responses can occur on rapid (ecological) timescales, and yet studiestypically do not consider the role that adaptive evolution will play in modulating biologicalresponses to climate change. Investigations into such responses have typically been focusedat particular biological levels (e.g., cellular, population, community), often lackinginteractions among levels. Since all levels of biological organisation are sensitive to globalclimate change, there is a need to elucidate how different processes and hierarchicalinteractions will influence species fitness. Therefore, predicting the responses ofcommunities and populations to global change will require multidisciplinary efforts acrossmultiple levels of hierarchy, from the genetic and cellular to communities and ecosystems.Eventually, this may allow us to establish the role that acclimatisation and adaptation willplay in determining marine community structures in future scenarios.
|
|
8. |
|
|
9. |
- Dahl, F, et al.
(author)
-
Imaging single DNA molecules for high precision NIPT
- 2018
-
In: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 8:1, s. 4549-
-
Journal article (peer-reviewed)abstract
- Cell-free DNA analysis is becoming adopted for first line aneuploidy screening, however for most healthcare programs, cost and workflow complexity is limiting adoption of the test. We report a novel cost effective method, the Vanadis NIPT assay, designed for high precision digitally-enabled measurement of chromosomal aneuploidies in maternal plasma. Reducing NIPT assay complexity is achieved by using novel molecular probe technology that specifically label target chromosomes combined with a new readout format using a nanofilter to enrich single molecules for imaging and counting without DNA amplification, microarrays or sequencing. The primary objective of this study was to assess the Vanadis NIPT assay with respect to analytical precision and clinical feasibility. Analysis of reference DNA samples indicate that samples which are challenging to analyze with low fetal-fraction can be readily detected with a limit of detection determined at <2% fetal-fraction. In total of 286 clinical samples were analysed and 30 out of 30 pregnancies affected by trisomy 21 were classified correctly. This method has the potential to make cost effective NIPT more widely available with more women benefiting from superior detection and false positive rates.
|
|
10. |
- Edberg, Niklas J. T., et al.
(author)
-
Atmospheric erosion of Venus during stormy space weather
- 2011
-
In: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 116, s. A09308-
-
Journal article (peer-reviewed)abstract
- We study atmospheric escape from Venus during solar minimum conditions when 147 corotating interaction regions (CIRs) and interplanetary coronal mass ejections (ICMEs) combined impact on the planet. This is the largest study to date of the effects of stormy space weather on Venus and we show for the first time statistically that the atmosphere of Venus is significantly affected by CIRs and ICMEs. When such events impact on Venus, as observed by the ACE and Venus Express satellites, the escape rate of Venus's ionosphere is measured to increase by a factor of 1.9, on average, compared to quiet solar wind times. However, the increase in escape flux during impacts can occasionally be significantly larger by orders of magnitude. Taking into account the occurrence rate of such events we find that roughly half (51%) of the outflow occurs during stormy space weather. Furthermore, we particularly discuss the importance of the increased solar wind dynamic pressure as well as the polarity change of the interplanetary magnetic field (IMF) in terms of causing the increase escape rate. The IMF polarity change across a CIR/ICME could cause dayside magnetic reconnection processes to occur in the induced magnetosphere of Venus, which would add to the erosion through associated particle acceleration.
|
|
11. |
- Rees, R. M., et al.
(author)
-
Nitrous oxide emissions from European agriculture; an analysis of variability and drivers of emissions from field experiments
- 2012
-
In: Biogeosciences Discussions. - : Copernicus GmbH. - 1810-6277. ; 9:7, s. 9259-9288
-
Journal article (peer-reviewed)abstract
- Nitrous oxide emissions from a network of agricultural experiments in Europe and Zimbabwe were used to explore the relative importance of site and management controls of emissions. At each site, a selection of management interventions were compared 5 within replicated experimental designs in plot based experiments. Arable experiments were conducted at Beano in Italy, El Encin in Spain, Foulum in Denmark, Logården in Sweden, Maulde in Belgium, Paulinenaue in Germany, Harare in Zimbabwe and Tulloch in the UK. Grassland experiments were conducted at Crichton, Nafferton and Peaknaze in the UK, Gödöllö in Hungary, Rzecin in Poland, Zarnekow in Germany and 10 Theix in France. Nitrous oxide emissions were measured at each site over a period of at least two years using static chambers. Emissions varied widely between sites and as a result of manipulation treatments. Average site emissions (throughout the study period) varied between 0.04 and 21.21 kg N2O-N ha−1 yr−1, with the largest fluxes and variability associated with the grassland sites. Total nitrogen addition was found to be 15 the single most important determinant of emissions, accounting for 15% of the variance (using linear regression) in the data from the arable sites (p < 0.0001), and 77% in the grassland sites. The annual emissions from arable sites were significantly greater than those that would be predicted by IPCC default emission factors. Variability in N2O within sites that occurred as a result of manipulation treatments was greater than that 20 resulting from site to site and year to year variation, highlighting the importance of management interventions in contributing to greenhouse gas mitigation.
|
|
12. |
|
|
13. |
- Stenberg, Å M, et al.
(author)
-
Lack of distant migration after injection of a 125iodine labeled dextranomer based implant into the rabbit bladder
- 1997
-
In: Journal of Urology. - 0022-5347 .- 1527-3792. ; 158:5, s. 1937-1941
-
Journal article (peer-reviewed)abstract
- PURPOSE:In recent years endoscopic treatment of stress incontinence and vesicoureteral reflux has been introduced. Reports of possible particle migration of the injected material to distant organs in humans and experimental animals have led to a search for biological nonmigration products. An implant found to have a good clinical effect in these conditions is dextranomer in hyaluronan. We performed this study in rabbits to investigate the possible migration of dextranomer particles.MATERIALS AND METHODS:125Iodine labeled dextranomer particles were injected into the submucosal space of rabbit bladders, and samples of blood and various tissues were examined for radioactivity at scheduled intervals during a 28-day period. Furthermore, whole body autoradiography was performed 1 day, and 1 and 4 weeks after injection.RESULTS:Radioactivity was found in blood samples and in all tissues but it remained at the background activity level except in the thyroid, where uptake representing free 125iodine was detected. In the bladder 41 and 45% of the injected dose remained within the bladder wall 1 day and 4 weeks, respectively, after injection. The remainder of the dose probably disappeared from the bladder wall by leakage into the urine shortly after deposition, as indicated by the finding of 10-fold higher urine radioactivity levels at day 1 than at day 28 after injection.CONCLUSIONS:No distant migration of dextranomer particles occurs after submucosal injection of such an implant in the rabbit bladder wall.
|
|
14. |
|
|
15. |
|
|
16. |
|
|
17. |
- Backrud, M., et al.
(author)
-
Cluster observations and theoretical explanations of broadband waves in the auroral region
- 2005
-
In: Annales Geophysicae. - : Copernicus Publications. - 1432-0576. ; 23, s. 3739-3752
-
Journal article (peer-reviewed)abstract
- Broadband waves are common on auroral field lines. We use two different methods to study the polarization of the waves at 10 to 180 Hz observed by the Cluster spacecraft at altitudes of about 4 Earth radii in the nightside auroral region. Observations of electric and magnetic wave fields, together with electron and ion data, are used as input to the methods. We find that much of the wave emissions are consistent with linear waves in homogeneous plasma. Observed waves with a large electric field perpendicular to the geomagnetic field are more common (electrostatic ion cyclotron waves), while ion acoustic waves with a large parallel electric field appear in smaller regions without suprathermal (tens of eV) plasma. The regions void of suprathermal plasma are interpreted as parallel potential drops of a few hundred volts.
|
|
18. |
|
|
19. |
- Bergman, Sofia, et al.
(author)
-
Spacecraft potential effects on low-energy ion measurements to be made by probe B1 of Comet Interceptor
- 2024
-
In: RAS Techniques and Instruments. - : Oxford University Press (OUP). - 2752-8200. ; 3:1, s. 333-346
-
Journal article (peer-reviewed)abstract
- Spacecraft charging causes notorious issues for low-energy plasma measurements. The charged particles are accelerated towards or repelled from the spacecraft surface, affecting both their energy and travel direction. The latter results in a distortion of the effective field of view (FOV) of the instrument making the measurements. The Comet Interceptor mission, planned to be launched in 2029, will make a flyby of a long-period or interstellar comet that ideally is dynamically new. The mission comprises one main spacecraft A, developed by the European Space Agency (ESA), and two sub-probes B1 and B2, developed by the Japan Aerospace Exploration Agency and ESA, respectively. The low-energy plasma measurements made by Comet Interceptor will likely be affected by the spacecraft potential in the case of low relative flyby velocities. On probe B1, the Cometary Ion Mass Spectrometer (CIMS) of the Plasma Suite is an ion mass spectrometer, capable of measuring ions with energies down to 10 eV/q. In this work, we use the Spacecraft Plasma Interaction Software to study the influence of the spacecraft potential on the low-energy ion measurements to be made by CIMS in the inner cometary magnetosphere. The results show that the effective FOV of CIMS is distorted at low energies when the flyby velocity is low. The distortion level is highly geometry dependent, and the largest distortions are caused by the magnetometer boom. Furthermore, the results show that cold ions with bulk velocities in the range 1-10 km s-1, flowing both radially away from and inward towards the nucleus, are detectable by the instrument considering the nominal observation geometry.
|
|
20. |
|
|
21. |
|
|
22. |
- de Peppo, G.M., et al.
(author)
-
Human Embryonic Mesodermal Progenitors Highly Resemble Human Mesenchymal Stem Cells and Display High Potential for Tissue Engineering Applications
- 2010
-
In: Tissue Engineering. Part A. - : Mary Ann Liebert. - 1937-3341 .- 1937-335X. ; 16:7, s. 2161-2182
-
Journal article (peer-reviewed)abstract
- Adult stem cells, such as human mesenchymal stem cells (hMSCs), show limited proliferative capacity and, after long-term culture, lose their differentiation capacity and are therefore not an optimal cell source for tissue engineering. Human embryonic stem cells (hESCs) constitute an important new resource in this field, but one major drawback is the risk of tumor formation in the recipients. One alternative is to use progenitor cells derived from hESCs which are more lineage restricted but do not form teratomas. We have recently derived a cell line from hESCs denoted human embryonic stem cell-derived mesodermal progenitors (hESMPs) and here, using genome wide microarray analysis, report that the process of hES-MPs derivation results in a significantly altered expression of hESCs characteristic genes to an expression level highly similar to that of hMSCs. However, hES-MPs displayed a significantly higher proliferative capacity and longer telomeres. Interestingly, the hES-MPs also demonstrated a lower expression of HLA class II proteins before and after interferon-γ treatment, indicating that these cells may somewhat be immunoprivileged and potentially used for HLA-incompatible transplantation. The hES-MPs are thus an appealing alternative to hMSCs in tissue engineering applications and stem cell-based therapies for mesodermal tissues.
|
|
23. |
- Edberg, Niklas J. T., et al.
(author)
-
Solar wind interaction with comet 67P : Impacts of corotating interaction regions
- 2016
-
In: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 121:2, s. 949-965
-
Journal article (peer-reviewed)abstract
- We present observations from the Rosetta Plasma Consortium of the effects of stormy solar wind on comet 67P/Churyumov-Gerasimenko. Four corotating interaction regions (CIRs), where the first event has possibly merged with a coronal mass ejection, are traced from Earth via Mars (using Mars Express and Mars Atmosphere and Volatile EvolutioN mission) to comet 67P from October to December 2014. When the comet is 3.1-2.7AU from the Sun and the neutral outgassing rate approximate to 10(25)-10(26)s(-1), the CIRs significantly influence the cometary plasma environment at altitudes down to 10-30km. The ionospheric low-energy (approximate to 5eV) plasma density increases significantly in all events, by a factor of >2 in events 1 and 2 but less in events 3 and 4. The spacecraft potential drops below -20V upon impact when the flux of electrons increases. The increased density is likely caused by compression of the plasma environment, increased particle impact ionization, and possibly charge exchange processes and acceleration of mass-loaded plasma back to the comet ionosphere. During all events, the fluxes of suprathermal (approximate to 10-100eV) electrons increase significantly, suggesting that the heating mechanism of these electrons is coupled to the solar wind energy input. At impact the magnetic field strength in the coma increases by a factor of 2-5 as more interplanetary magnetic field piles up around the comet. During two CIR impact events, we observe possible plasma boundaries forming, or moving past Rosetta, as the strong solar wind compresses the cometary plasma environment. We also discuss the possibility of seeing some signatures of the ionospheric response to tail disconnection events.
|
|
24. |
- Edberg, Niklas J. T., et al.
(author)
-
Spatial distribution of low-energy plasma around comet 67P/CG from Rosetta measurements
- 2015
-
In: Geophysical Research Letters. - 0094-8276 .- 1944-8007. ; 42:11, s. 4263-4269
-
Journal article (peer-reviewed)abstract
- We use measurements from the Rosetta plasma consortium Langmuir probe and mutual impedance probe to study the spatial distribution of low-energy plasma in the near-nucleus coma of comet 67P/Churyumov-Gerasimenko. The spatial distribution is highly structured with the highest density in the summer hemisphere and above the region connecting the two main lobes of the comet, i.e., the neck region. There is a clear correlation with the neutral density and the plasma to neutral density ratio is found to be approximate to 1-210(-6), at a cometocentric distance of 10km and at 3.1AU from the Sun. A clear 6.2h modulation of the plasma is seen as the neck is exposed twice per rotation. The electron density of the collisionless plasma within 260km from the nucleus falls off with radial distance as approximate to 1/r. The spatial structure indicates that local ionization of neutral gas is the dominant source of low-energy plasma around the comet.
|
|
25. |
|
|
26. |
|
|
27. |
- Feil, S. C., et al.
(author)
-
Crystallization and preliminary X-ray analysis of glutathione transferases from cyanobacteria
- 2009
-
In: Acta Crystallographica. Section F. - 1744-3091 .- 1744-3091. ; 65, s. 475-477
-
Journal article (peer-reviewed)abstract
- Glutathione S-transferases (GSTs) are a group of multifunctional enzymes that are found in animals, plants and microorganisms. Their primary function is to remove toxins derived from exogenous sources or the products of metabolism from the cell. Mammalian GSTs have been extensively studied, in contrast to bacterial GSTs which have received relatively scant attention. A new class of GSTs called Chi has recently been identified in cyanobacteria. Chi GSTs exhibit a high glutathionylation activity towards isothiocyanates, compounds that are normally found in plants. Here, the crystallization of two GSTs are presented: TeGST produced by Thermosynechococcus elongates BP-1 and SeGST from Synechococcus elongates PCC 6301. Both enzymes formed crystals that diffracted to high resolution and appeared to be suitable for further X-ray diffraction studies. The structures of these GSTs may shed further light on the evolution of GST catalytic activity and in particular why these enzymes possess catalytic activity towards plant antimicrobial compounds.
|
|
28. |
|
|
29. |
- Fredell, L, et al.
(author)
-
Heredity of hypospadias and the significance of low birth weight
- 2002
-
In: Journal of Urology. - 1527-3792 .- 0022-5347. ; 3, s. 1423-
-
Journal article (peer-reviewed)abstract
- Purpose: We analyzed a large group of patients with hypospadias regarding familial aggregation, phenotype, twin rate and ethnic origin and assessed the correlation of low birth weight with hypospadias. Materials and Methods: We mailed questionnaires to 2,503 boys operated on for hypospadias in Sweden asking for additional cases of hypospadias in the family, the number of brothers in the nuclear family, and birth weight of the boys with hypospadias and their brothers. Results: Of the boys 7% reported 1 or more additional family members with hypospadias. The birth weight of the boys with hypospadias was significantly lower (p = 5 X 10(-13)) than the birth weight of their unaffected brothers. Phenotyping of 676 individuals revealed glandular hypospadias in 53%, penile forms in 39%, penoscrotal or perineal variants in 6% and cleaved prepuce as the only manifestation in 2%. There were 50% more twins than expected compared to the general population and established zygosity in 83% (67% monozygotic, 33% dizygotic). Non-Swedish ethnicity was noted in 22% of the subjects, a third of whom were from Middle Eastern countries. Conclusions: We present data on heredity, birth weight, phenotype and ethnic origin in a large group of patients with hypospadias. The finding of additional members with hypospadias in 7% of the families supports the concept that genetic factors are involved in the pathogenesis. The strong association with low birth weight may be explained by genetic and environmental factors.
|
|
30. |
|
|
31. |
|
|
32. |
|
|
33. |
- Halonen, Lena, et al.
(author)
-
A study of mailroom runnability and the occurrence of unplanned Stops
- 2004
-
Conference paper (peer-reviewed)abstract
- The different causes of mailroom stops, downtime, and reduced production speed in the mailroom are discussed. It is stated that inserting and stacker stops might cause longer down time in the mailroom that force the press to be stopped. Stops in the packaging lines can be handled to the production through increased personnel efforts by the production staff in the mailroom. The total downtime for the press caused by the mailroom varies from 8 to about 21 minutes. Additional studies are needed to support any further conclusions on minor stops.
|
|
34. |
|
|
35. |
- Hollman, P, et al.
(author)
-
Tribological evaluation of thermally activated CVD diamond-like carbon (DLC) coatings
- 1997
-
In: SURFACE & COATINGS TECHNOLOGY. - 0257-8972. ; 96:2-3, s. 230-235
-
Journal article (other academic/artistic)abstract
- Diamond-lie carbon coatings have been the subject of expanding technological interest for wear resistance and low friction applications during recent years. In this study diamond-like carbon coatings were deposited by thermally activated chemical vapour
|
|
36. |
|
|
37. |
- Johansson, Henrik, et al.
(author)
-
Targeted resequencing of candidate genes using Selector Probes
- 2011
-
In: Nucleic Acids Research. - : Oxford University Press (OUP). - 0305-1048 .- 1362-4962. ; 39:2, s. e8-
-
Journal article (peer-reviewed)abstract
- Targeted genome enrichment is a powerful tool for making use of the massive throughput of novel DNA-sequencing instruments. We herein present a simple and scalable protocol for multiplex amplification of target regions based on the Selector technique. The updated version exhibits improved coverage and compatibility with next-generation-sequencing (NGS) library-construction procedures for shotgun sequencing with NGS platforms. To demonstrate the performance of the technique, all 501 exons from 28 genes frequently involved in cancer were enriched for and sequenced in specimens derived from cell lines and tumor biopsies. DNA from both fresh frozen and formalin-fixed paraffin-embedded biopsies were analyzed and 94 specificity and 98 coverage of the targeted region was achieved. Reproducibility between replicates was high (R 2=0, 98) and readily enabled detection of copy-number variations. The procedure can be carried out in <24 h and does not require any dedicated instrumentation.
|
|
38. |
- Katayama, S., et al.
(author)
-
Acute wheeze-specific gene module shows correlation with vitamin D and asthma medication
- 2020
-
In: European Respiratory Journal. - : NLM (Medline). - 0903-1936 .- 1399-3003. ; 55:1
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Airway obstruction and wheezing in preschool children with recurrent viral infections are a major clinical problem, and are recognised as a risk factor for the development of chronic asthma. We aimed to analyse whether gene expression profiling provides evidence for pathways that delineate distinct groups of children with wheeze, and in combination with clinical information could contribute to diagnosis and prognosis of disease development. METHODS: We analysed leukocyte transcriptomes from preschool children (6 months-3 years) at acute wheeze (n=107), and at a revisit 2-3 months later, comparing them to age-matched healthy controls (n=66). RNA-sequencing applying GlobinLock was used. The cases were followed clinically until age 7 years. Differential expression tests, weighted correlation network analysis and logistic regression were applied and correlations to 76 clinical traits evaluated. FINDINGS: Significant enrichment of genes involved in the innate immune responses was observed in children with wheeze. We identified a unique acute wheeze-specific gene-module, which was associated with vitamin D levels (p<0.005) in infancy, and asthma medication and FEV1%/FVC (forced expiratory volume in 1 s/forced vital capacity) ratio several years later, at age 7 years (p<0.005). A model that predicts leukotriene receptor antagonist medication at 7 years of age with high accuracy was developed (area under the curve 0.815, 95% CI 0.668-0.962). INTERPRETATION: Gene expression profiles in blood from preschool wheezers predict asthma symptoms at school age, and therefore serve as biomarkers. The acute wheeze-specific gene module suggests that molecular phenotyping in combination with clinical information already at an early episode of wheeze may help to distinguish children who will outgrow their wheeze from those who will develop chronic asthma.
|
|
39. |
|
|
40. |
- Larsson, S, et al.
(author)
-
The generation of fermentation inhibitors during dilute acid hydrolysis of softwood
- 1999
-
In: Enzyme and Microbial Technology. - 0141-0229. ; 24:3-4, s. 151-159
-
Journal article (peer-reviewed)abstract
- The influence of the severity of dilute sulfuric acid hydrolysis of spruce (softwood) on sugar yield and on the fermentability of the hydrolysate by Saccharomyces cerevisiae (Baker's yeast) was investigated. Fermentability was assessed as the ethanol yield on fermentable sugars (mannose and glucose) and the mean volumetric productivity (4 h). The hydrolysis conditions, residence time, temperature, and sulfuric acid concentration were treated as a single parameter, combined severity (CS). When the CS of the hydrolysis conditions increased, the yield of fermentable sugars increased to a maximum between CS 2.0-2.7 for mannose, and 3.0-3.4 for glucose above which it decreased. The decrease in the yield of monosaccharides coincided with the maximum concentrations of furfural and 5-hydroxymethylfurfural (5HMF). With the further increase in CS, the concentrations of furfural and 5-HMF decreased while the formation of formic acid and levulinic acid increased The yield of ethanol decreased at approximately CS 3; however, the volumetric productivity decreased at lower CS. The effect of acetic acid, formic acid, levulinic acid furfural, and 5-HMF on fermentability was assayed in model fermentations Ethanol yield and volumetric productivity decreased with increasing concentrations of acetic acid, formic acid, and levulinic acid. Furfural and 5-HMF decreased the volumetric productivity but did not influence the final yield of ethanol. The decrease in volumetric productivity was more pronounced when 5-HMF was added to the fermentation, and this compound was depleted at a lower rate than furfural. The inhibition observed in hydrolysates produced in higher CS could not be fully explained by the effect of the by-products furfural, 5-HMF, acetic acid, formic acid: and levulinic acid. (C) 1998 Elsevier Science Inc.
|
|
41. |
|
|
42. |
- Mandt, K. E., et al.
(author)
-
RPC observation of the development and evolution of plasma interaction boundaries at 67P/Churyumov-Gerasimenko
- 2016
-
In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 462, s. S9-S22
-
Journal article (peer-reviewed)abstract
- One of the primary objectives of the Rosetta Plasma Consortium, a suite of five plasma instruments on-board the Rosetta spacecraft, is to observe the formation and evolution of plasma interaction regions at the comet 67P/Churyumov-Gerasimenko (67P/CG). Observations made between 2015 April and 2016 February show that solar wind-cometary plasma interaction boundaries and regions formed around 2015 mid-April and lasted through early 2016 January. At least two regions were observed, separated by an ion-neutral collisionopause boundary. The inner region was located on the nucleus side of the boundary and was characterized by low-energy water-group ions, reduced magnetic field pileup and enhanced electron densities. The outer region was located outside of the boundary and was characterized by reduced electron densities, water-group ions that are accelerated to energies above 100 eV and enhanced magnetic field pileup compared to the inner region. The boundary discussed here is outside of the diamagnetic cavity and shows characteristics similar to observations made on-board the Giotto spacecraft in the ion pileup region at 1P/Halley. We find that the boundary is likely to be related to ion-neutral collisions and that its location is influenced by variability in the neutral density and the solar wind dynamic pressure.
|
|
43. |
|
|
44. |
|
|
45. |
|
|
46. |
- Niespodziana, K, et al.
(author)
-
PreDicta chip-based high resolution diagnosis of rhinovirus-induced wheeze
- 2018
-
In: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 9:1, s. 2382-
-
Journal article (peer-reviewed)abstract
- Rhinovirus (RV) infections are major triggers of acute exacerbations of severe respiratory diseases such as pre-school wheeze, asthma and chronic obstructive pulmonary disease (COPD). The occurrence of numerous RV types is a major challenge for the identification of the culprit virus types and for the improvement of virus type-specific treatment strategies. Here, we develop a chip containing 130 different micro-arrayed RV proteins and peptides and demonstrate in a cohort of 120 pre-school children, most of whom had been hospitalized due to acute wheeze, that it is possible to determine the culprit RV species with a minute blood sample by serology. Importantly, we identify RV-A and RV-C species as giving rise to most severe respiratory symptoms. Thus, we have generated a chip for the serological identification of RV-induced respiratory illness which should be useful for the rational development of preventive and therapeutic strategies targeting the most important RV types.
|
|
47. |
- Nilsson, Hans, et al.
(author)
-
Evolution of the ion environment of comet 67P/Churyumov-Gerasimenko
- 2015
-
In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 583
-
Journal article (peer-reviewed)abstract
- Context. The Rosetta spacecraft is escorting comet 67P/Churyumov-Gerasimenko from a heliocentric distance of >3.6 AU, where the comet activity was low, until perihelion at 1.24 AU. Initially, the solar wind permeates the thin comet atmosphere formed from sublimation. Aims. Using the Rosetta Plasma Consortium Ion Composition Analyzer (RPC-ICA), we study the gradual evolution of the comet ion environment, from the first detectable traces of water ions to the stage where cometary water ions accelerated to about 1 keV energy are abundant. We compare ion fluxes of solar wind and cometary origin. Methods. RPC-ICA is an ion mass spectrometer measuring ions of solar wind and cometary origins in the 10 eV-40 keV energy range. Results. We show how the flux of accelerated water ions with energies above 120 eV increases between 3.6 and 2.0 AU. The 24 h average increases by 4 orders of magnitude, mainly because high-flux periods become more common. The water ion energy spectra also become broader with time. This may indicate a larger and more uniform source region. At 2.0 AU the accelerated water ion flux is frequently of the same order as the solar wind proton flux. Water ions of 120 eV-few keV energy may thus constitute a significant part of the ions sputtering the nucleus surface. The ion density and mass in the comet vicinity is dominated by ions of cometary origin. The solar wind is deflected and the energy spectra broadened compared to an undisturbed solar wind. Conclusions. The flux of accelerated water ions moving from the upstream direction back toward the nucleus is a strongly nonlinear function of the heliocentric distance.
|
|
48. |
- Nilsson, H., et al.
(author)
-
Ion distributions in the vicinity of Mars : Signatures of heating and acceleration processes
- 2012
-
In: Earth Planets and Space. - : Springer Science and Business Media LLC. - 1343-8832 .- 1880-5981. ; 64:2, s. 135-148
-
Journal article (peer-reviewed)abstract
- More than three years of data from the ASPERA-3 instrument on-board Mars Express has been used to compile average distribution functions of ions in and around the Mars induced magnetosphere. We present samples of average distribution functions, as well as average flux patterns based on the average distribution functions, all suitable for detailed comparison with models of the near-Mars space environment. The average heavy ion distributions close to the planet form thermal populations with a temperature of 3 to 10 eV. The distribution functions in the tail consist of two populations, one cold which is an extension of the low altitude population, and one accelerated population of ionospheric origin ions. All significant fluxes of heavy ions in the tail are tailward. The heavy ions in the magnetosheath form a plume with the flow aligned with the bow shock, and a more radial flow direction than the solar wind origin flow. Summarizing the escape processes, ionospheric ions are heated close to the planet, presumably through wave-particle interaction. These heated populations are accelerated in the tailward direction in a restricted region. Another significant escape path is through the magnetosheath. A part of the ionospheric population is likely accelerated in the radial direction, out into the magnetosheath, although pick up of an oxygen exosphere may also be a viable source for this escape. Increased energy input from the solar wind during CIR events appear to mainly increase the number flux of escaping particles, the average energy of the escaping particles is not strongly affected. Heavy ions on the dayside may precipitate and cause sputtering of the atmosphere, though fluxes are likely lower than 0.4 x 10(23) s(-1).
|
|
49. |
|
|
50. |
|
|