| 1. |
- Abelev, Betty, et al.
(author)
-
Long-range angular correlations on the near and away side in p-Pb collisions at root S-NN=5.02 TeV
- 2013
-
In: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 719:1-3, s. 29-41
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Journal article (peer-reviewed)abstract
- Angular correlations between charged trigger and associated particles are measured by the ALICE detector in p-Pb collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV for transverse momentum ranges within 0.5 < P-T,P-assoc < P-T,P-trig < 4 GeV/c. The correlations are measured over two units of pseudorapidity and full azimuthal angle in different intervals of event multiplicity, and expressed as associated yield per trigger particle. Two long-range ridge-like structures, one on the near side and one on the away side, are observed when the per-trigger yield obtained in low-multiplicity events is subtracted from the one in high-multiplicity events. The excess on the near-side is qualitatively similar to that recently reported by the CMS Collaboration, while the excess on the away-side is reported for the first time. The two-ridge structure projected onto azimuthal angle is quantified with the second and third Fourier coefficients as well as by near-side and away-side yields and widths. The yields on the near side and on the away side are equal within the uncertainties for all studied event multiplicity and p(T) bins, and the widths show no significant evolution with event multiplicity or p(T). These findings suggest that the near-side ridge is accompanied by an essentially identical away-side ridge. (c) 2013 CERN. Published by Elsevier B.V. All rights reserved.
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| 2. |
- Abelev, Betty, et al.
(author)
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Measurement of prompt J/psi and beauty hadron production cross sections at mid-rapidity in pp collisions at root s=7 TeV
- 2012
-
In: Journal of High Energy Physics. - 1029-8479. ; :11
-
Journal article (peer-reviewed)abstract
- The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at root s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L-int = 5.6 nb(-1). The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum p(t) > 1,3 GeV/c and rapidity vertical bar y vertical bar < 0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the psi(2S) and chi(c) resonances, is sigma(prompt J/psi) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 8.3 +/- 0.8(stat.) +/- 1.1 (syst.)(-1.4)(+1.5) (syst. pol.) mu b. The cross section for the production of b-hadrons decaying to J/psi with p(t) > 1.3 GeV/c and vertical bar y vertical bar < 0.9 is a sigma(J/psi <- hB) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 1.46 +/- 0.38 (stat.)(-0.32)(+0.26) (syst.) mu b. The results are compared to QCD model predictions. The shape of the p(t) and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the b (b) over bar pair total cross section and d sigma/dy at mid-rapidity.
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| 3. |
- Abelev, Betty, et al.
(author)
-
Underlying Event measurements in pp collisions at root s=0.9 and 7 TeV with the ALICE experiment at the LHC
- 2012
-
In: Journal of High Energy Physics. - 1029-8479. ; :7
-
Journal article (peer-reviewed)abstract
- We present measurements of Underlying Event observables in pp collisions at root s = 0 : 9 and 7 TeV. The analysis is performed as a function of the highest charged-particle transverse momentum p(T),L-T in the event. Different regions are defined with respect to the azimuthal direction of the leading (highest transverse momentum) track: Toward, Transverse and Away. The Toward and Away regions collect the fragmentation products of the hardest partonic interaction. The Transverse region is expected to be most sensitive to the Underlying Event activity. The study is performed with charged particles above three different p(T) thresholds: 0.15, 0.5 and 1.0 GeV/c. In the Transverse region we observe an increase in the multiplicity of a factor 2-3 between the lower and higher collision energies, depending on the track p(T) threshold considered. Data are compared to PYTHIA 6.4, PYTHIA 8.1 and PHOJET. On average, all models considered underestimate the multiplicity and summed p(T) in the Transverse region by about 10-30%.
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| 4. |
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| 5. |
- Kuehlewein, Laura, et al.
(author)
-
Clinical phenotype and course of PDE6A-associated retinitis pigmentosa disease, characterized in preparation for a gene supplementation trial
- 2020
-
In: JAMA Ophthalmology. - : American Medical Association (AMA). - 2168-6165. ; 138:12, s. 1241-1250
-
Journal article (peer-reviewed)abstract
- IMPORTANCE Treatment trials require sound knowledge on the natural course of disease. OBJECTIVE To assess clinical features, genetic findings, and genotype-phenotype correlations in patients with retinitis pigmentosa (RP) associated with biallelic sequence variations in the PDE6A gene in preparation for a gene supplementation trial. DESIGN, SETTING, AND PARTICIPANTS This prospective, longitudinal, observational cohort study was conducted from January 2001 to December 2019 in a single center (Centre for Ophthalmology of the University of Tübingen, Germany) with patients recruited multinationally from 12 collaborating European tertiary referral centers. Patients with retinitis pigmentosa, sequence variants in PDE6A, and the ability to provide informed consent were included. EXPOSURES Comprehensive ophthalmological examinations; validation of compound heterozygosity and biallelism by familial segregation analysis, allelic cloning, or assessment of next-generation sequencing-read data, where possible. MAIN OUTCOMES AND MEASURES Genetic findings and clinical features describing the entire cohort and comparing patients harboring the 2 most common disease-causing variants in a homozygous state (c.304C>A;p.(R102S) and c.998 + 1G>A;p.?). RESULTS Fifty-seven patients (32 female patients [56%]; mean [SD], 40 [14] years) from 44 families were included. All patients completed the study. Thirty patients were homozygous for disease-causing alleles. Twenty-seven patients were heterozygous for 2 different PDE6A variants each. The most frequently observed alleles were c.304C>A;p.(R102S), c.998 + 1G>A;p.?, and c.2053G>A;p.(V685M). The mean (SD) best-corrected visual acuity was 0.43 (0.48) logMAR (Snellen equivalent, 20/50). The median visual field area with object III4e was 660 square degrees (5th and 95th percentiles, 76 and 11 019 square degrees; 25th and 75th percentiles, 255 and 3923 square degrees). Dark-adapted and light-adapted full-field electroretinography showed no responses in 88 of 108 eyes (81.5%). Sixty-nine of 108 eyes (62.9%) showed additional findings on optical coherence tomography imaging (eg, cystoid macular edema or macular atrophy). The variant c.998 + 1G>A;p.? led to a more severe phenotype when compared with the variant c.304C>A;p.(R102S). CONCLUSIONS AND RELEVANCE Seventeen of the PDE6A variants found in these patients appeared to be novel. Regarding the clinical findings, disease was highly symmetrical between the right and left eyes and visual impairment was mild or moderate in 90% of patients, providing a window of opportunity for gene therapy.
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| 6. |
- Windirsch, Torben, et al.
(author)
-
Large herbivores on permafrost : a pilot study of grazing impacts on permafrost soil carbon storage in northeastern Siberia
- 2022
-
In: Frontiers in Environmental Science. - : Frontiers Media S.A.. - 2296-665X. ; 10
-
Journal article (peer-reviewed)abstract
- The risk of carbon emissions from permafrost is linked to an increase in ground temperature and thus in particular to thermal insulation by vegetation, soil layers and snow cover. Ground insulation can be influenced by the presence of large herbivores browsing for food in both winter and summer. In this study, we examine the potential impact of large herbivore presence on the soil carbon storage in a thermokarst landscape in northeastern Siberia. Our aim in this pilot study is to conduct a first analysis on whether intensive large herbivore grazing may slow or even reverse permafrost thaw by affecting thermal insulation through modifying ground cover properties. As permafrost soil temperatures are important for organic matter decomposition, we hypothesize that herbivory disturbances lead to differences in ground-stored carbon. Therefore, we analyzed five sites with a total of three different herbivore grazing intensities on two landscape forms (drained thermokarst basin, Yedoma upland) in Pleistocene Park near Chersky. We measured maximum thaw depth, total organic carbon content, δ13C isotopes, carbon-nitrogen ratios, and sediment grain-size composition as well as ice and water content for each site. We found the thaw depth to be shallower and carbon storage to be higher in intensively grazed areas compared to extensively and non-grazed sites in the same thermokarst basin. First data show that intensive grazing leads to a more stable thermal ground regime and thus to increased carbon storage in the thermokarst deposits and active layer. However, the high carbon content found within the upper 20 cm on intensively grazed sites could also indicate higher carbon input rather than reduced decomposition, which requires further studies including investigations of the hydrology and general ground conditions existing prior to grazing introduction. We explain our findings by intensive animal trampling in winter and vegetation changes, which overcompensate summer ground warming. We conclude that grazing intensity—along with soil substrate and hydrologic conditions—might have a measurable influence on the carbon storage in permafrost soils. Hence the grazing effect should be further investigated for its potential as an actively manageable instrument to reduce net carbon emission from permafrost.
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| 7. |
- Adam, Stefan, et al.
(author)
-
Quartz crystal microbalance with coupled Spectroscopic Ellipsometry-study of temperature-responsive polymer brush systems
- 2017
-
In: Applied Surface Science. - : ELSEVIER SCIENCE BV. - 0169-4332 .- 1873-5584. ; 421, s. 843-851
-
Journal article (peer-reviewed)abstract
- Using a combined setup of quartz crystal microbalance with dissipation monitoring together with spectroscopic ellipsometry, the thermo-responsive behavior of two different brush systems (poly(N-isopropyl acrylamide) and poly(2-oxazoline)s) was investigated and compared to the behavior of the free polymer in solution. Poly(2-oxazoline)s with three different hydrophilicities were prepared by changing the content of a hydrophilic comonomer. While both polymer types exhibit a sharp, discontinuous thermal transition in solution, in the brush state the transition gets broader in the case of poly(N-isopropyl acrylamide) and is transformed into a continuous transition for poly(2-oxazoline)s. The position of the transition in solution is influenced by the degree of hydrophilicity of the poly(2-oxazoline). The difference in areal mass detected by quartz crystal microbalance and by spectroscopic ellipsometry, has been attributed to the chain segment density profile of the polymer brushes. Applying this density profile information, for poly(N-isopropyl acrylamide) two different swelling stages could be identified, while for poly(2-oxazoline) the transition between a parabolic and more step-wise profile is found continuous. The different swelling characteristics were attributed to the different miscibility behavior types, with the brush state acting similar to a crosslinked system. (C) 2017 Elsevier B.V. All rights reserved.
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| 8. |
- Birgersson, Simon, et al.
(author)
-
Flexibility and Function of Distal Substrate-Binding Tryptophans in the Blue Mussel β-Mannanase MeMan5A and Their Role in Hydrolysis and Transglycosylation
- 2023
-
In: Catalysts. - 2073-4344. ; 13:9
-
Journal article (peer-reviewed)abstract
- β-Mannanases hydrolyze β-mannans, important components of plant and microalgae cell walls. Retaining β-mannanases can also catalyze transglycosylation, forming new β-mannosidic bonds that are applicable for synthesis. This study focused on the blue mussel (Mytilus edulis) GH5_10 β-mannanase MeMan5A, which contains two semi-conserved tryptophans (W240 and W281) in the distal subsite +2 of its active site cleft. Variants of MeMan5A were generated by replacing one or both tryptophans with alanines. The substitutions reduced the enzyme’s catalytic efficiency (kcat/Km using galactomannan) by three-fold (W281A), five-fold (W240A), or 20-fold (W240A/W281A). Productive binding modes were analyzed by 18O labeling of hydrolysis products and mass spectrometry. Results show that the substitution of both tryptophans was required to shift away from the dominant binding mode of mannopentaose (spanning subsites −3 to +2), suggesting that both tryptophans contribute to glycan binding. NMR spectroscopy and molecular dynamics simulations were conducted to analyze protein flexibility and glycan binding. We suggest that W240 is rigid and contributes to +2 subsite mannosyl specificity, while W281 is flexible, which enables stacking interactions in the +2 subsite by loop movement to facilitate binding. The substitutions significantly reduced or eliminated transglycosylation with saccharides as glycosyl acceptors but had no significant effect on reactions with alcohols.
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| 9. |
- Bock, Thomas, et al.
(author)
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Proteomic Analysis Reveals Drug Accessible Cell Surface N-Glycoproteins of Primary and Established Glioblastoma Cell Lines
- 2012
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In: Journal of Proteome Research. - : American Chemical Society (ACS). - 1535-3893 .- 1535-3907. ; 11:10, s. 4885-4893
-
Journal article (peer-reviewed)abstract
- Glioblastoma is the most common primary Glioblastoma Cell Surface Capturing brain tumor in adults with low average survival time after diagnosis. In order to improve glioblastoma treatment, new drug-accessible targets need to be identified. Cell surface glycoproteins are prime drug targets due to their accessibility at the surface of cancer cells. To overcome the limited availability of suitable antibodies for cell surface protein detection, we performed a comprehensive mass spectrometric investigation of the glioblastoma surfaceome. Our combined cell surface capturing analysis of primary ex vivo glioblastoma cell lines in combination with established glioblastoma cell lines revealed 633 N-glycoproteins, which vastly extends the known data of surfaceome drug targets at subcellular resolution. We provide direct evidence of common glioblastoma cell surface glycoproteins and an approximate estimate of their abundances, information that could not be derived from genomic and/or transcriptomic glioblastoma studies. Apart from our pharmaceutically valuable repertoire of already and potentially drug-accessible cell surface glycoproteins, we built a mass-spectrometry-based toolbox enabling directed, sensitive, and repetitive glycoprotein measurements for clinical follow-up studies. The included Skyline Glioblastoma SRM assay library provides an elevated starting point for parallel testing of the abundance level of the detected glioblastoma surfaceome members in future drug perturbation experiments.
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| 10. |
- Cramer, Joel, et al.
(author)
-
Spin transport across antiferromagnets induced by the spin Seebeck effect
- 2018
-
In: Journal of Physics D. - : IOP PUBLISHING LTD. - 0022-3727 .- 1361-6463. ; 51:14
-
Journal article (peer-reviewed)abstract
- For prospective spintronics devices based on the propagation of pure spin currents, antiferromagnets are an interesting class of materials that potentially entail a number of advantages as compared to ferromagnets. Here, we present a detailed theoretical study of magnonic spin current transport in ferromagnetic-antiferromagnetic multilayers by using atomistic spin dynamics simulations. The relevant length scales of magnonic spin transport in antiferromagnets are determined. We demonstrate the transfer of angular momentum from a ferromagnet into an antiferromagnet due to the excitation of only one magnon branch in the antiferromagnet. As an experimental system, we ascertain the transport across an antiferromagnet in Y3Fe5O12 vertical bar Ir20Mn80 vertical bar Pt heterostructures. We determine the spin transport signals for spin currents generated in the Y3Fe5O12 by the spin Seebeck effect and compare to measurements of the spin Hall magnetoresistance in the heterostructure stack. By means of temperature-dependent and thickness-dependent measurements, we deduce conclusions on the spin transport mechanism across Ir20Mn80 and furthermore correlate it to its paramagnetic-antiferromagnetic phase transition.
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| 11. |
- Dohi, Takaaki, et al.
(author)
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Enhanced thermally-activated skyrmion diffusion with tunable effective gyrotropic force
- 2023
-
In: Nature Communications. - : Springer Nature. - 2041-1723. ; 14:1
-
Journal article (peer-reviewed)abstract
- Magnetic skyrmions, topologically-stabilized spin textures that emerge in magnetic systems, have garnered considerable interest due to a variety of electromagnetic responses that are governed by the topology. The topology that creates a microscopic gyrotropic force also causes detrimental effects, such as the skyrmion Hall effect, which is a well-studied phenomenon highlighting the influence of topology on the deterministic dynamics and drift motion. Furthermore, the gyrotropic force is anticipated to have a substantial impact on stochastic diffusive motion; however, the predicted repercussions have yet to be demonstrated, even qualitatively. Here we demonstrate enhanced thermally-activated diffusive motion of skyrmions in a specifically designed synthetic antiferromagnet. Suppressing the effective gyrotropic force by tuning the angular momentum compensation leads to a more than 10 times enhanced diffusion coefficient compared to that of ferromagnetic skyrmions. Consequently, our findings not only demonstrate the gyro-force dependence of the diffusion coefficient but also enable ultimately energy-efficient unconventional stochastic computing.
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| 12. |
- Hauber, Ernst, et al.
(author)
-
DEBRIS FLOW FANS AND PERMAFROST LANDFORMS ON SVALBARD (NORWAY): TERRESTRIAL ANALOGUES FOR MARTIAN MID-LATITUDE PERIGLACIAL LANDSCAPES.
- 2010
-
In: 41st Lunar and Planetary Science Conference. ; :1922
-
Conference paper (peer-reviewed)abstract
- Many young landforms on Mars that were probably formed by exogenic processes show a latitude- dependent geographic distribution. They include surface mantling, lobate debris aprons, lineated valley fill, and concentric crater fill, viscous flow features, gullies, and patterned ground. Collectively, these landforms are hypothesized to represent the surface records of Martian ice ages that were induced by astronomical forcing and associated climate changes. Previous studies often considered just one of the features in isolation (e.g., gullies), without taking into account the geomorphologic context. A more comprehensive investigation of the full assemblage of landforms (landscape analysis), however, has the potential to reduce the ambiguity in interpreting landforms (the problem of equifinality, e.g., in the case of pingos), and to reveal the evolution of the climatic environment in more detail. Here we present permafrost landforms of Svalbard (Norway) as useful terrestrial analogues for the suite of possible periglacial landforms that are typically found at mid-latitudes on Mars. We build on our previous investigations of gullies and fans, and include a number of classical periglacial landforms (patterned ground, rock glaciers, pingos) that all have close morphological analogues on Mars. Based on this comparison, we propose an evolutionary scenario which helps to understand the sequential formation of the Martian landforms into their present state.
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| 13. |
- Hauber, Ernst, et al.
(author)
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Periglacial landscapes on Svalbard: Terrestrial analogs for cold-climate landforms on Mars
- 2011
-
In: The Geological Society of America, Special Paper. - : Geological Society of America. ; 483
-
Journal article (peer-reviewed)abstract
- We present landforms on Svalbard (Norway) as terrestrial analogs for possible Martian periglacial surface features. While there are closer climatic analogs for Mars, e.g., the Antarctic Dry Valleys, Svalbard has unique advantages that make it a very useful study area. Svalbard is easily accessible and offers a periglacial landscape where many different landforms can be encountered in close spatial proximity. These landforms include thermal contraction cracks, slope stripes, rock glaciers, protalus ramparts, and pingos, all of which have close morphological analogs on Mars. The combination of remotesensing data, in particular images and digital elevation models, with field work is a promising approach in analog studies and facilitates acquisition of fi rst-hand experience with permafrost environments. Based on the morphological ambiguity of certain landforms such as pingos, we recommend that Martian cold-climate landforms should not be investigated in isolation, but as part of a landscape system in a geological context.
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| 14. |
- Hauber, Ernst, et al.
(author)
-
Svalbard (Norway) as a terrestrial analogue for Martian landforms: Results on
- 2009
-
In: EPSC Abstracts. European Planetary Science Congress. ; 4, EPSC2009-772
-
Conference paper (peer-reviewed)abstract
- Small alluvial fan-like landforms have been observed on Mars in association with recent gullies. Such fans are relatively small (km-scale) when compared to large alluvial fans on Mars, which can reach dimensions of tens of kilometers. The small fans are part of an erosion-transportsedimentation system (alcove-channel-apron). Morphologically very similar systems can be studied on Svalbard (Norway), which is a cold and dry polar desert and, therefore, a potentially useful terrestrial analogue for Mars` climate and climaterelated landforms. Here we give an update on our field work in summer 2008 and a simultaneous flight campaign with an airborne version (HRSCAX) of the High Resolution Stereo Camera (HRSC) onboard Mars Express. We also present very preliminary results from the field campaign in summer 2009.
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| 15. |
- Heintz, Søren, et al.
(author)
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Development of in situ product removal strategies in biocatalysis applying scaled-down unit operations
- 2017
-
In: Biotechnology and Bioengineering. - : Wiley. - 0006-3592. ; 114:3, s. 600-609
-
Journal article (peer-reviewed)abstract
- An experimental platform based on scaled-down unit operations combined in a plug-and-play manner enables easy and highly flexible testing of advanced biocatalytic process options such as in situ product removal (ISPR) process strategies. In such a platform, it is possible to compartmentalize different process steps while operating it as a combined system, giving the possibility to test and characterize the performance of novel process concepts and biocatalysts with minimal influence of inhibitory products. Here the capabilities of performing process development by applying scaled-down unit operations are highlighted through a case study investigating the asymmetric synthesis of 1-methyl-3-phenylpropylamine (MPPA) using ω-transaminase, an enzyme in the sub-family of amino transferases (ATAs). An on-line HPLC system was applied to avoid manual sample handling and to semi-automatically characterize ω-transaminases in a scaled-down packed-bed reactor (PBR) module, showing MPPA as a strong inhibitor. To overcome the inhibition, a two-step liquid–liquid extraction (LLE) ISPR concept was tested using scaled-down unit operations combined in a plug-and-play manner. Through the tested ISPR concept, it was possible to continuously feed the main substrate benzylacetone (BA) and extract the main product MPPA throughout the reaction, thereby overcoming the challenges of low substrate solubility and product inhibition. The tested ISPR concept achieved a product concentration of 26.5 gMPPA · L−1, a purity up to 70% gMPPA · gtot −1 and a recovery in the range of 80% mol · mol−1 of MPPA in 20 h, with the possibility to increase the concentration, purity, and recovery further. Biotechnol. Bioeng. 2017;114: 600–609.
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| 16. |
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| 17. |
- Johnsson, Andreas, 1977, et al.
(author)
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POSSIBLE FREEZE AND THAW LANDFROMS ON HIGH-LATITUDE SLOPES ON MARS: INSIGHTS FROM TERRESTRIAL ANALOGS IN SPITSBERGEN, SVALBARD.
- 2011
-
In: 42nd Lunar and Planetary Science Conference. ; 42:2758
-
Conference paper (peer-reviewed)abstract
- Solifluction lobes are common slope features in Polar Regions on Earth where freeze and thaw processes occur. Mars is currently a cold and barren planet with its water resources locked up in ice caps, glaciers and ice-enriched permafrost. However, features resembling solifluction lobes have been observed on high-latitude slopes on Mars and in most, but not all, cases in close proximity to gullies. Lobes are found on steep inner crater walls and in planform they show striking resemblance to terrestrial solifluction lobes. These observations may point to a late phase in Mars history with transient melt water in local environments. In our study we have examined solifluction lobes on slopes in Svalbard in order to compare to the Martian lobate landforms. Specific questions we address are: how widely distributed are these lobate landforms on Mars and how do they relate to known ground-ice related landforms?
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| 18. |
- Johnsson, Andreas, 1977, et al.
(author)
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POSSIBLE FREEZE/THAW LANDFORMS ON MARTIAN SLOPES: USING SVALBARD ADVENT VALLEY AS AN ANALOGUE TO MARS.
- 2010
-
In: Third European Conference on Permafrost. - 9788248100102 ; 2010, s. 58-58
-
Conference paper (other academic/artistic)abstract
- Stripes and gelifluction lobes are common slope features in polar regions on Earth where freeze and thaw processes occur. Mars is currently a cold and barren planet with its water resources locked up as ice caps and ice-rich permafrost. However, features resembling stripes and gelifluction lobes have been observed on high-latitude slopes on Mars and in most, but not all, cases in close proximity to gullies. Stripe width typically ranges from ~50 cm to 1.5 m, and their orientation is consistently down slope, although it can not be excluded that it sometimes slightly deviates from the steepest topographic gradient. Lobes are found on steep inner crater walls and display similar dimensions as terrestrial gelifluction lobes. These observations may point to a late phase in Mars history with transient melt water in local niches. In our study we have examined sorted and non-sorted stripes as well as gelifluction lobes on slopes in Svalbard in order to test the working hypothesis of a freeze and thaw origin of the Martian landforms.
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| 19. |
- Johnsson, Andreas, 1977, et al.
(author)
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THE ORIGIN OF STRIPE-LIKE PATTERNS ON MARTIAN GULLY SLOPES; USING SVALBARD ADVENT VALLEY AS A MARS ANALOGUE.
- 2010
-
In: 41st Lunar and Planetary Science Conference. ; :1665
-
Conference paper (other academic/artistic)abstract
- Stripes are a common slope features in polar regions on Earth were active layer processes (freezing/thawing and gelifluction) occur. Their origin is most likely polygenic and closely related to frost crack plygons and sorted circles with the addition of a gravitational component. Stripes are either sorted or unsorted. Features resembling stripes have been observed on slopes on Mars with or without association with polygons. Due to the current temperature and pressure regime on Mars soil moisture and active layer processes are not likely to occur. However, in recent HiRISE images stripelike patterns can be observed in proximity to gullies . Stripe width typically ranges from ~50 cm to 1.5 m, and their orientation is consistently down slope, although it can not be excluded that it sometimes slightly deviates from the steepest topographic gradient. In our study we have examined sorted and nonsorted stripes on slopes in Svalbard in order to test the working hypothesis of an cryoturbation origin for the martian stripe-like patterns. In doing so we compare their morphological characteristics, settings, and slope to those on Mars.
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| 20. |
- Joshi, Peter K, et al.
(author)
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Directional dominance on stature and cognition in diverse human populations
- 2015
-
In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 523:7561, s. 459-462
-
Journal article (peer-reviewed)abstract
- Homozygosity has long been associated with rare, often devastating, Mendelian disorders, and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness. However, the effect of the more distant parental relatedness that is common in modern human populations is less well understood. Genomic data now allow us to investigate the effects of homozygosity on traits of public health importance by observing contiguous homozygous segments (runs of homozygosity), which are inferred to be homozygous along their complete length. Given the low levels of genome-wide homozygosity prevalent in most human populations, information is required on very large numbers of people to provide sufficient power. Here we use runs of homozygosity to study 16 health-related quantitative traits in 354,224 individuals from 102 cohorts, and find statistically significant associations between summed runs of homozygosity and four complex traits: height, forced expiratory lung volume in one second, general cognitive ability and educational attainment (P < 1 × 10(-300), 2.1 × 10(-6), 2.5 × 10(-10) and 1.8 × 10(-10), respectively). In each case, increased homozygosity was associated with decreased trait value, equivalent to the offspring of first cousins being 1.2 cm shorter and having 10 months' less education. Similar effect sizes were found across four continental groups and populations with different degrees of genome-wide homozygosity, providing evidence that homozygosity, rather than confounding, directly contributes to phenotypic variance. Contrary to earlier reports in substantially smaller samples, no evidence was seen of an influence of genome-wide homozygosity on blood pressure and low density lipoprotein cholesterol, or ten other cardio-metabolic traits. Since directional dominance is predicted for traits under directional evolutionary selection, this study provides evidence that increased stature and cognitive function have been positively selected in human evolution, whereas many important risk factors for late-onset complex diseases may not have been.
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| 21. |
- Kaschina, Elena, et al.
(author)
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Angiotensin II type 2 receptor stimulation : a novel option of therapeutic interference with the renin-angiotensin system in myocardial infarction?
- 2008
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In: Circulation. - 0009-7322 .- 1524-4539. ; 118:24, s. 2523-32
-
Journal article (peer-reviewed)abstract
- BACKGROUND: This study is the first to examine the effect of direct angiotensin II type 2 (AT(2)) receptor stimulation on postinfarct cardiac function with the use of the novel nonpeptide AT(2) receptor agonist compound 21 (C21). METHODS AND RESULTS: Myocardial infarction (MI) was induced in Wistar rats by permanent ligation of the left coronary artery. Treatment with C21 (0.01, 0.03, 0.3 mg/kg per day IP) was started 24 hours after MI and was continued until euthanasia (7 days after MI). Infarct size was assessed by magnetic resonance imaging, and hemodynamic measurements were performed via transthoracic Doppler echocardiography and intracardiac Millar catheter. Cardiac tissues were analyzed for inflammation and apoptosis markers with immunoblotting and real-time reverse transcription polymerase chain reaction. C21 significantly improved systolic and diastolic ventricular function. Scar size was smallest in the C21-treated rats. In regard to underlying mechanisms, C21 diminished MI-induced Fas-ligand and caspase-3 expression in the peri-infarct zone, indicating an antiapoptotic effect. Phosphorylation of the p44/42 and p38 mitogen-activated protein kinases, both involved in the regulation of cell survival, was strongly reduced after MI but almost completely rescued by C21 treatment. Furthermore, C21 decreased MI-induced serum monocyte chemoattractant protein-1 and myeloperoxidase as well as cardiac interleukin-6, interleukin-1beta, and interleukin-2 expression, suggesting an antiinflammatory effect. CONCLUSIONS: Direct AT(2) receptor stimulation may be a novel therapeutic approach to improve post-MI systolic and diastolic function by antiapoptotic and antiinflammatory mechanisms.
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| 22. |
- Lamond, Angus I., et al.
(author)
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Advancing Cell Biology Through Proteomics in Space and Time (PROSPECTS)
- 2012
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In: Molecular & Cellular Proteomics. - 1535-9476 .- 1535-9484. ; 11:3
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Journal article (peer-reviewed)abstract
- The term "proteomics" encompasses the large-scale detection and analysis of proteins and their post-translational modifications. Driven by major improvements in mass spectrometric instrumentation, methodology, and data analysis, the proteomics field has burgeoned in recent years. It now provides a range of sensitive and quantitative approaches for measuring protein structures and dynamics that promise to revolutionize our understanding of cell biology and molecular mechanisms in both human cells and model organisms. The Proteomics Specification in Time and Space (PROSPECTS) Network is a unique EU-funded project that brings together leading European research groups, spanning from instrumentation to biomedicine, in a collaborative five year initiative to develop new methods and applications for the functional analysis of cellular proteins. This special issue of Molecular and Cellular Proteomics presents 16 research papers reporting major recent progress by the PROSPECTS groups, including improvements to the resolution and sensitivity of the Orbitrap family of mass spectrometers, systematic detection of proteins using highly characterized antibody collections, and new methods for absolute as well as relative quantification of protein levels. Manuscripts in this issue exemplify approaches for performing quantitative measurements of cell proteomes and for studying their dynamic responses to perturbation, both during normal cellular responses and in disease mechanisms. Here we present a perspective on how the proteomics field is moving beyond simply identifying proteins with high sensitivity toward providing a powerful and versatile set of assay systems for characterizing proteome dynamics and thereby creating a new "third generation"proteomics strategy that offers an indispensible tool for cell biology and molecular medicine.
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| 23. |
- Lehmann, Christian, et al.
(author)
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Robot Joint Modeling and Parameter Identification Using the Clamping Method
- 2013
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In: 7th IFAC Conference on Manufacturing Modelling, Management, and Control, 2013. - 1474-6670. - 9783902823359 ; , s. 813-818
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Conference paper (peer-reviewed)abstract
- The usage of industrial robots for milling tasks is limited by their lack of absolute accuracy in presence of process forces. While there are techniques and products available for increasing the absolute accuracy of free-space motions, the mechanical weaknesses of the robot in combination with the milling forces limits the achievable performance. If the dynamic effects causing the deviations can be compensated for, there would be several benefits of using industrial robots for machining applications. To enable the compensation, the causes of the path deviations have to be adequately modeled, and there must be a method for determining the model parameters in a simple and inexpensive way. To that end, we propose a radically new method for identification of robot joint model parameters, based on clamping of the robot to a rigid environment. The rigidity of the environment then eliminates the need for expensive measurement equipment, and the internal sensors of the robot give sufficient feedback. An experimental validation shows the feasibility of the method.
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| 24. |
- Lindemann, Ulrich, et al.
(author)
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Maximum step length as a potential screening tool for falls in non-disabled older adults living in the community.
- 2008
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In: Aging Clinical and Experimental Research. - 1594-0667 .- 1720-8319. ; 20:5, s. 394-9
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Journal article (peer-reviewed)abstract
- BACKGROUND AND AIMS: Identification of the risk of falls in a cohort of interest is a prerequisite for a targeted fall prevention study. Motor tasks are widely used as baseline assessment in such studies, but there are only a few well-evaluated tests of motor performance to predict falls prospectively. This study was conducted to find out if the potential of the maximum step length (MSL) test can predict future falls in non-disabled older persons. METHODS: A modified version of the MSL test was used for baseline assessment in 56 community-dwelling, non-disabled elderly persons (mean age 67.7 yrs, SD 6 yrs; 57% women). During a follow-up of 1 year, falls were recorded in a daily calendar. RESULTS: During the follow-up, 30 persons (54%) fell, with no gender difference in reporting of falls between men and women. The adjusted mean valid step length and adjusted maximum valid step length were predictive of future falls with a sensitivity/specificity of 77%/62% and 70%/69%, respectively. Combining MSL test results with fall history increased sensitivity to 93% and 90%, respectively, but decreased specificity to 54% and 58%, respectively. CONCLUSIONS: The MSL test is a feasible tool, with low requirements in space, predicting future falls in community-dwelling older persons. In combination with history of falls, the sensitivity of the test increased considerably.
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| 25. |
- Mardinoglu, Adil, 1982, et al.
(author)
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An Integrated Understanding of the Rapid Metabolic Benefits of a Carbohydrate-Restricted Diet on Hepatic Steatosis in Humans
- 2018
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In: Cell Metabolism. - : Elsevier BV. - 1550-4131 .- 1932-7420. ; 27:3
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Journal article (peer-reviewed)abstract
- A carbohydrate-restricted diet is a widely recommended intervention for non-alcoholic fatty liver disease (NAFLD), but a systematic perspective on the multiple benefits of this diet is lacking. Here, we performed a short-term intervention with an isocaloric low-carbohydrate diet with increased protein content in obese subjects with NAFLD and characterized the resulting alterations in metabolism and the gut microbiota using a multi-omics approach. We observed rapid and dramatic reductions of liver fat and other cardiometabolic risk factors paralleled by (1) marked decreases in hepatic de novo lipogenesis; (2) large increases in serum beta-hydroxybutyrate concentrations, reflecting increased mitochondrial beta-oxidation; and (3) rapid increases in folate-producing Streptococcus and serum folate concentrations. Liver transcriptomic analysis on biopsy samples from a second cohort revealed downregulation of the fatty acid synthesis pathway and upregulation of folate-mediated one-carbon metabolism and fatty acid oxidation pathways. Our results highlight the potential of exploring diet-microbiota interactions for treating NAFLD.
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