| 1. |
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| 2. |
- Li, W. Y., et al.
(författare)
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Electron Bernstein waves driven by electron crescents near the electron diffusion region
- 2020
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Ingår i: Nature Communications. - : Nature Research. - 2041-1723. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- The Magnetospheric Multiscale (MMS) spacecraft encounter an electron diffusion region (EDR) of asymmetric magnetic reconnection at Earth’s magnetopause. The EDR is characterized by agyrotropic electron velocity distributions on both sides of the neutral line. Various types of plasma waves are produced by the magnetic reconnection in and near the EDR. Here we report large-amplitude electron Bernstein waves (EBWs) at the electron-scale boundary of the Hall current reversal. The finite gyroradius effect of the outflow electrons generates the crescent-shaped agyrotropic electron distributions, which drive the EBWs. The EBWs propagate toward the central EDR. The amplitude of the EBWs is sufficiently large to thermalize and diffuse electrons around the EDR. The EBWs contribute to the cross-field diffusion of the electron-scale boundary of the Hall current reversal near the EDR.
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| 3. |
- Halliday, Alison, et al.
(författare)
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10-year stroke prevention after successful carotid endarterectomy for asymptomatic stenosis (ACST-1) : A multicentre randomised trial
- 2010
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Ingår i: The Lancet. - 0140-6736 .- 1474-547X. ; 376:9746, s. 1074-1084
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Tidskriftsartikel (refereegranskat)abstract
- Background If carotid artery narrowing remains asymptomatic (ie, has caused no recent stroke or other neurological symptoms), successful carotid endarterectomy (CEA) reduces stroke incidence for some years. We assessed the long-term effects of successful CEA. Methods Between 1993 and 2003, 3120 asymptomatic patients from 126 centres in 30 countries were allocated equally, by blinded minimised randomisation, to immediate CEA (median delay 1 month, IQR 0·3-2·5) or to indefinite deferral of any carotid procedure, and were followed up until death or for a median among survivors of 9 years (IQR 6-11). The primary outcomes were perioperative mortality and morbidity (death or stroke within 30 days) and non-perioperative stroke. Kaplan-Meier percentages and logrank p values are from intention-to-treat analyses. This study is registered, number ISRCTN26156392. Findings 1560 patients were allocated immediate CEA versus 1560 allocated deferral of any carotid procedure. The proportions operated on while still asymptomatic were 89·7 versus 4·8 at 1 year (and 92·1 vs 16·5 at 5 years). Perioperative risk of stroke or death within 30 days was 3·0 (95 CI 2·4-3·9; 26 non-disabling strokes plus 34 disabling or fatal perioperative events in 1979 CEAs). Excluding perioperative events and non-stroke mortality, stroke risks (immediate vs deferred CEA) were 4·1 versus 10·0 at 5 years (gain 5·9, 95 CI 4·0-7·8) and 10·8 versus 16·9 at 10 years (gain 6·1, 2·7-9·4); ratio of stroke incidence rates 0·54, 95 CI 0·43-0·68, p<0·0001. 62 versus 104 had a disabling or fatal stroke, and 37 versus 84 others had a non-disabling stroke. Combining perioperative events and strokes, net risks were 6·9 versus 10·9 at 5 years (gain 4·1, 2·0-6·2) and 13·4 versus 17·9 at 10 years (gain 4·6, 1·2-7·9). Medication was similar in both groups; throughout the study, most were on antithrombotic and antihypertensive therapy. Net benefits were significant both for those on lipid-lowering therapy and for those not, and both for men and for women up to 75 years of age at entry (although not for older patients). Interpretation Successful CEA for asymptomatic patients younger than 75 years of age reduces 10-year stroke risks. Half this reduction is in disabling or fatal strokes. Net benefit in future patients will depend on their risks from unoperated carotid lesions (which will be reduced by medication), on future surgical risks (which might differ from those in trials), and on whether life expectancy exceeds 10 years. Funding UK Medical Research Council, BUPA Foundation, Stroke Association.
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| 4. |
- Khotyaintsev, Yuri V., et al.
(författare)
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Electron jet of asymmetric reconnection
- 2016
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Ingår i: Geophysical Research Letters. - : Blackwell Publishing. - 0094-8276 .- 1944-8007. ; 43:11, s. 5571-5580
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Tidskriftsartikel (refereegranskat)abstract
- We present Magnetospheric Multiscale observations of an electron-scale current sheet and electron outflow jet for asymmetric reconnection with guide field at the subsolar magnetopause. The electron jet observed within the reconnection region has an electron Mach number of 0.35 and is associated with electron agyrotropy. The jet is unstable to an electrostatic instability which generates intense waves with E-vertical bar amplitudes reaching up to 300mVm(-1) and potentials up to 20% of the electron thermal energy. We see evidence of interaction between the waves and the electron beam, leading to quick thermalization of the beam and stabilization of the instability. The wave phase speed is comparable to the ion thermal speed, suggesting that the instability is of Buneman type, and therefore introduces electron-ion drag and leads to braking of the electron flow. Our observations demonstrate that electrostatic turbulence plays an important role in the electron-scale physics of asymmetric reconnection.
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| 5. |
- Li, Wenya, et al.
(författare)
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Kinetic evidence of magnetic reconnection due to Kelvin-Helmholtz waves
- 2016
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Ingår i: Geophysical Research Letters. - : Blackwell Publishing. - 0094-8276 .- 1944-8007. ; 43:11, s. 5635-5643
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Tidskriftsartikel (refereegranskat)abstract
- The Kelvin-Helmholtz (KH) instability at the Earth's magnetopause is predominantly excited during northward interplanetary magnetic field (IMF). Magnetic reconnection due to KH waves has been suggested as one of the mechanisms to transfer solar wind plasma into the magnetosphere. We investigate KH waves observed at the magnetopause by the Magnetospheric Multiscale (MMS) mission; in particular, we study the trailing edges of KH waves with Alfvenic ion jets. We observe gradual mixing of magnetospheric and magnetosheath ions at the boundary layer. The magnetospheric electrons with energy up to 80keV are observed on the magnetosheath side of the jets, which indicates that they escape into the magnetosheath through reconnected magnetic field lines. At the same time, the low-energy (below 100eV) magnetosheath electrons enter the magnetosphere and are heated in the field-aligned direction at the high-density edge of the jets. Our observations provide unambiguous kinetic evidence for ongoing reconnection due to KH waves.
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| 6. |
- Li, Wenya, et al.
(författare)
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Upper-Hybrid Waves Driven by Meandering Electrons Around Magnetic Reconnection X Line
- 2021
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Ingår i: Geophysical Research Letters. - : American Geophysical Union (AGU). - 0094-8276 .- 1944-8007. ; 48:16
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Tidskriftsartikel (refereegranskat)abstract
- Magnetic reconnection is a fundamental process in collisionless space plasma environment, and plasma waves relevant to the kinetic interactions can have a significant impact on the multiscale behavior of reconnection. Here, we present Magnetospheric Multiscale (MMS) observations during an encounter of an X line of symmetric magnetic reconnection in the magnetotail. The X line is characterized by reversals of ion and electron jets and electromagnetic fields, agyrotropic electron velocity distribution functions (VDFs), and an electron-scale current sheet. MMS observe large-amplitude nonlinear upper-hybrid (UH) waves on both sides of the neutral line, and the wave amplitudes have highly localized distribution along the normal direction. The inbound meandering electrons drive the UH waves, releasing the free energy stored from the reconnection electric field along the meandering trajectories. The interaction between the meandering electrons and the UH waves may modify the balance of the reconnection electric field around the X line. Plain Language Summary The electron-scale kinetic physics in the electron diffusion region (EDR) controls how magnetic field lines break and reconnect. Electron crescent, an indicator of EDR, can drive high-frequency electrostatic waves around EDR. For the first time, the upper-hybrid (UH) waves are observed on both sides of the X line and we show the direct association between the UH waves and the reconnection electric field. The strong wave-electron interaction can change the electron-scale dynamics and may modify the reconnection electric field. This study demonstrates that the UH waves may play an important role in controlling the reconnection rate.
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| 7. |
- André, Mats, et al.
(författare)
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Magnetic reconnection and modification of the Hall physics due to cold ions at the magnetopause
- 2016
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Ingår i: Geophysical Research Letters. - : Blackwell Publishing. - 0094-8276 .- 1944-8007. ; 43:13, s. 6705-6712
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Tidskriftsartikel (refereegranskat)abstract
- Observations by the four Magnetospheric Multiscale spacecraft are used to investigate the Hall physics of a magnetopause magnetic reconnection separatrix layer. Inside this layer of currents and strong normal electric fields, cold (eV) ions of ionospheric origin can remain frozen-in together with the electrons. The cold ions reduce the Hall current. Using a generalized Ohm's law, the electric field is balanced by the sum of the terms corresponding to the Hall current, the vxB drifting cold ions, and the divergence of the electron pressure tensor. A mixture of hot and cold ions is common at the subsolar magnetopause. A mixture of length scales caused by a mixture of ion temperatures has significant effects on the Hall physics of magnetic reconnection.
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| 8. |
- Graham, D. B., et al.
(författare)
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Direct observations of anomalous resistivity and diffusion in collisionless plasma
- 2022
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- Coulomb collisions provide plasma resistivity and diffusion but in many low-density astrophysical plasmas such collisions between particles are extremely rare. Scattering of particles by electromagnetic waves can lower the plasma conductivity. Such anomalous resistivity due to wave-particle interactions could be crucial to many processes, including magnetic reconnection. It has been suggested that waves provide both diffusion and resistivity, which can support the reconnection electric field, but this requires direct observation to confirm. Here, we directly quantify anomalous resistivity, viscosity, and cross-field electron diffusion associated with lower hybrid waves using measurements from the four Magnetospheric Multiscale (MMS) spacecraft. We show that anomalous resistivity is approximately balanced by anomalous viscosity, and thus the waves do not contribute to the reconnection electric field. However, the waves do produce an anomalous electron drift and diffusion across the current layer associated with magnetic reconnection. This leads to relaxation of density gradients at timescales of order the ion cyclotron period, and hence modifies the reconnection process. It is suggested that waves can provide both diffusion and resistivity that can potentially support the reconnection electric field in low-density astrophysical plasmas. Here, the authors show, using direct spacecraft measurements, that the waves contribute to anomalous diffusion but do not contribute to the reconnection electric field.
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| 9. |
- Graham, Daniel B., et al.
(författare)
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Electron currents and heating in the ion diffusion region of asymmetric reconnection
- 2016
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Ingår i: Geophysical Research Letters. - : American Geophysical Union (AGU). - 0094-8276 .- 1944-8007. ; 43:10, s. 4691-4700
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Tidskriftsartikel (refereegranskat)abstract
- In this letter the structure of the ion diffusion region of magnetic reconnection at Earth's magnetopause is investigated using the Magnetospheric Multiscale (MMS) spacecraft. The ion diffusion region is characterized by a strong DC electric field, approximately equal to the Hall electric field, intense currents, and electron heating parallel to the background magnetic field. Current structures well below ion spatial scales are resolved, and the electron motion associated with lower hybrid drift waves is shown to contribute significantly to the total current density. The electron heating is shown to be consistent with large-scale parallel electric fields trapping and accelerating electrons, rather than wave-particle interactions. These results show that sub-ion scale processes occur in the ion diffusion region and are important for understanding electron heating and acceleration.
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| 10. |
- Graham, Daniel B., et al.
(författare)
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Lower hybrid waves in the ion diffusion and magnetospheric inflow regions
- 2017
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Ingår i: Journal of Geophysical Research - Space Physics. - : AMER GEOPHYSICAL UNION. - 2169-9380 .- 2169-9402. ; 122:1, s. 517-533
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Tidskriftsartikel (refereegranskat)abstract
- The role and properties of lower hybrid waves in the ion diffusion region and magnetospheric inflow region of asymmetric reconnection are investigated using the Magnetospheric Multiscale (MMS) mission. Two distinct groups of lower hybrid waves are observed in the ion diffusion region and magnetospheric inflow region, which have distinct properties and propagate in opposite directions along the magnetopause. One group develops near the ion edge in the magnetospheric inflow, where magnetosheath ions enter the magnetosphere through the finite gyroradius effect and are driven by the ion-ion cross-field instability due to the interaction between the magnetosheath ions and cold magnetospheric ions. This leads to heating of the cold magnetospheric ions. The second group develops at the sharpest density gradient, where the Hall electric field is observed and is driven by the lower hybrid drift instability. These drift waves produce cross-field particle diffusion, enabling magnetosheath electrons to enter the magnetospheric inflow region thereby broadening the density gradient in the ion diffusion region.
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| 11. |
- Graham, Daniel B., et al.
(författare)
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Universality of Lower Hybrid Waves at Earth's Magnetopause
- 2019
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Ingår i: Journal of Geophysical Research - Space Physics. - : John Wiley & Sons. - 2169-9380 .- 2169-9402. ; 124:11, s. 8727-8760
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Tidskriftsartikel (refereegranskat)abstract
- Waves around the lower hybrid frequency are frequently observed at Earth's magnetopause and readily reach very large amplitudes. Determining the properties of lower hybrid waves is crucial because they are thought to contribute to electron and ion heating, cross‐field particle diffusion, anomalous resistivity, and energy transfer between electrons and ions. All these processes could play an important role in magnetic reconnection at the magnetopause and the evolution of the boundary layer. In this paper, the properties of lower hybrid waves at Earth's magnetopause are investigated using the Magnetospheric Multiscale mission. For the first time, the properties of the waves are investigated using fields and direct particle measurements. The highest‐resolution electron moments resolve the velocity and density fluctuations of lower hybrid waves, confirming that electrons remain approximately frozen in at lower hybrid wave frequencies. Using fields and particle moments, the dispersion relation is constructed and the wave‐normal angle is estimated to be close to 90° to the background magnetic field. The waves are shown to have a finite parallel wave vector, suggesting that they can interact with parallel propagating electrons. The observed wave properties are shown to agree with theoretical predictions, the previously used single‐spacecraft method, and four‐spacecraft timing analyses. These results show that single‐spacecraft methods can accurately determine lower hybrid wave properties.
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| 12. |
- Hwang, K.-J., et al.
(författare)
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Bifurcated Current Sheet Observed on the Boundary of Kelvin-Helmholtz Vortices
- 2021
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Ingår i: Frontiers in Astronomy and Space Sciences. - : Frontiers Media S.A.. - 2296-987X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- On May 5, 2017 MMS observed a bifurcated current sheet at the boundary of Kelvin-Helmholtz vortices (KHVs) developed on the dawnside tailward magnetopause. We use the event to enhance our understanding of the formation and structure of asymmetric current sheets in the presence of density asymmetry, flow shear, and guide field, which have been rarely studied. The entire current layer comprises three separate current sheets, each corresponding to magnetosphere-side sunward separatrix region, central near-X-line region, and magnetosheath-side tailward separatrix region. Two off-center structures are identified as slow-mode discontinuities. All three current sheets have a thickness of ∼0.2 ion inertial length, demonstrating the sub-ion-scale current layer, where electrons mainly carry the current. We find that both the diamagnetic and electron anisotropy currents substantially support the bifurcated currents in the presence of density asymmetry and weak velocity shear. The combined effects of strong guide field, low density asymmetry, and weak flow shear appear to lead to asymmetries in the streamlines and the current-layer structure of the quadrupolar reconnection geometry. We also investigate intense electrostatics waves observed on the magnetosheath side of the KHV boundary. These waves may pre-heat a magnetosheath population that is to participate into the reconnection process, leading to two-step energization of the magnetosheath plasma entering into the magnetosphere via KHV-driven reconnection.
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| 13. |
- Le Contel, O., et al.
(författare)
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Lower Hybrid Drift Waves and Electromagnetic Electron Space-Phase Holes Associated With Dipolarization Fronts and Field-Aligned Currents Observed by the Magnetospheric Multiscale Mission During a Substorm
- 2017
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Ingår i: Journal of Geophysical Research - Space Physics. - : AMER GEOPHYSICAL UNION. - 2169-9380 .- 2169-9402. ; 122:12, s. 12236-12257
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Tidskriftsartikel (refereegranskat)abstract
- We analyze two ion scale dipolarization fronts associated with field-aligned currents detected by the Magnetospheric Multiscale mission during a large substorm on 10 August 2016. The first event corresponds to a fast dawnward flow with an antiparallel current and could be generated by the wake of a previous fast earthward flow. It is associated with intense lower hybrid drift waves detected at the front and propagating dawnward with a perpendicular phase speed close to the electric drift and the ion thermal velocity. The second event corresponds to a flow reversal: from southwward/dawnward to northward/duskward associated with a parallel current consistent with a brief expansion of the plasma sheet before the front crossing and with a smaller lower hybrid drift wave activity. Electromagnetic electron phase-space holes are detected near these low-frequency drift waves during both events. The drift waves could accelerate electrons parallel to the magnetic field and produce the parallel electron drift needed to generate the electron holes. Yet we cannot rule out the possibility that the drift waves are produced by the antiparallel current associated with the fast flows, leaving the source for the electron holes unexplained.
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| 14. |
- Li, Wenya Y., et al.
(författare)
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Cold Ionospheric Ions in the Magnetic Reconnection Outflow Region
- 2017
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Ingår i: Journal of Geophysical Research - Space Physics. - : Blackwell Publishing. - 2169-9380 .- 2169-9402. ; 122:10, s. 10,194-10,202
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Tidskriftsartikel (refereegranskat)abstract
- Magnetosheath plasma usually determines properties of asymmetric magnetic reconnection at the subsolar region of Earth's magnetopause. However, cold plasma that originated from the ionosphere can also reach the magnetopause and modify the kinetic physics of asymmetric reconnection. We present a magnetopause crossing with high-density (10–60 cm−3) cold ions and ongoing reconnection from the observation of the Magnetospheric Multiscale (MMS) spacecraft. The magnetopause crossing is estimated to be 300 ion inertial lengths south of the X line. Two distinct ion populations are observed on the magnetosheath edge of the ion jet. One population with high parallel velocities (200–300 km/s) is identified to be cold ion beams, and the other population is the magnetosheath ions. In the deHoffman-Teller frame, the field-aligned magnetosheath ions are Alfvénic and move toward the jet region, while the field-aligned cold ion beams move toward the magnetosheath boundary layer, with much lower speeds. These cold ion beams are suggested to be from the cold ions entering the jet close to the X line. This is the first observation of the cold ionospheric ions in the reconnection outflow region, including the reconnection jet and the magnetosheath boundary layer.
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| 15. |
- Norgren, Cecilia, et al.
(författare)
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Finite gyroradius effects in the electron outflow of asymmetric magnetic reconnection
- 2016
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Ingår i: Geophysical Research Letters. - : Blackwell Publishing. - 0094-8276 .- 1944-8007. ; 43:13, s. 6724-6733
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Tidskriftsartikel (refereegranskat)abstract
- We present observations of asymmetric magnetic reconnection showing evidence of electron demagnetization in the electron outflow. The observations were made at the magnetopause by the four Magnetospheric Multiscale (MMS) spacecraft, separated by approximate to 15km. The reconnecting current sheet has negligible guide field, and all four spacecraft likely pass close to the electron diffusion region just south of the X line. In the electron outflow near the X line, all four spacecraft observe highly structured electron distributions in a region comparable to a few electron gyroradii. The distributions consist of a core with T-vertical bar>T and a nongyrotropic crescent perpendicular to the magnetic field. The crescents are associated with finite gyroradius effects of partly demagnetized electrons. These observations clearly demonstrate the manifestation of finite gyroradius effects in an electron-scale reconnection current sheet.
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| 16. |
- Toledo-Redondo, S., et al.
(författare)
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Solar Wind-Magnetosphere Coupling During Radial Interplanetary Magnetic Field Conditions : Simultaneous Multi-Point Observations
- 2021
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Ingår i: Journal of Geophysical Research - Space Physics. - : American Geophysical Union (AGU). - 2169-9380 .- 2169-9402. ; 126:11
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Tidskriftsartikel (refereegranskat)abstract
- In-situ spacecraft missions are powerful assets to study processes that occur in space plasmas. One of their main limitations, however, is extrapolating such local measurements to the global scales of the system. To overcome this problem at least partially, multi-point measurements can be used. There are several multi-spacecraft missions currently operating in the Earth's magnetosphere, and the simultaneous use of the data collected by them provides new insights into the large-scale properties and evolution of magnetospheric plasma processes. In this work, we focus on studying the Earth's magnetopause (MP) using a conjunction between the Magnetospheric Multiscale and Cluster fleets, when both missions skimmed the MP for several hours at distant locations during radial interplanetary magnetic field (IMF) conditions. The observed MP positions as a function of the evolving solar wind conditions are compared to model predictions of the MP. We observe an inflation of the magnetosphere (similar to 0.7 R-E), consistent with magnetosheath pressure decrease during radial IMF conditions, which is less pronounced on the flank (<0.2 R-E). There is observational evidence of magnetic reconnection in the subsolar region for the whole encounter, and in the dusk flank for the last portion of the encounter, suggesting that reconnection was extending more than 15 R-E. However, reconnection jets were not always observed, suggesting that reconnection was patchy, intermittent or both. Shear flows reduce the reconnection rate up to similar to 30% in the dusk flank according to predictions, and the plasma beta enhancement in the magnetosheath during radial IMF favors reconnection suppression by the diamagnetic drift.
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| 17. |
- Vaivads, Andris, et al.
(författare)
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Turbulence Heating ObserveR - satellite mission proposal
- 2016
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Ingår i: JOURNAL OF PLASMA PHYSICS. - 0022-3778. ; 82
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Tidskriftsartikel (refereegranskat)abstract
- The Universe is permeated by hot, turbulent, magnetized plasmas. Turbulent plasma is a major constituent of active galactic nuclei, supernova remnants, the intergalactic and interstellar medium, the solar corona, the solar wind and the Earth's magnetosphere, just to mention a few examples. Energy dissipation of turbulent fluctuations plays a key role in plasma heating and energization, yet we still do not understand the underlying physical mechanisms involved. THOR is a mission designed to answer the questions of how turbulent plasma is heated and particles accelerated, how the dissipated energy is partitioned and how dissipation operates in different regimes of turbulence. THOR is a single-spacecraft mission with an orbit tuned to maximize data return from regions in near-Earth space - magnetosheath, shock, foreshock and pristine solar wind - featuring different kinds of turbulence. Here we summarize the THOR proposal submitted on 15 January 2015 to the 'Call for a Medium-size mission opportunity in ESAs Science Programme for a launch in 2025 (M4)'. THOR has been selected by European Space Agency (ESA) for the study phase.
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| 18. |
- Yordanova, Emiliya, et al.
(författare)
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Electron scale structures and magnetic reconnection signatures in the turbulent magnetosheath
- 2016
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Ingår i: Geophysical Research Letters. - : Blackwell Publishing. - 0094-8276 .- 1944-8007. ; 43:12, s. 5969-5978
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Tidskriftsartikel (refereegranskat)abstract
- Collisionless space plasma turbulence can generate reconnecting thin current sheets as suggested by recent results of numerical magnetohydrodynamic simulations. The Magnetospheric Multiscale (MMS) mission provides the first serious opportunity to verify whether small ion-electron-scale reconnection, generated by turbulence, resembles the reconnection events frequently observed in the magnetotail or at the magnetopause. Here we investigate field and particle observations obtained by the MMS fleet in the turbulent terrestrial magnetosheath behind quasi-parallel bow shock geometry. We observe multiple small-scale current sheets during the event and present a detailed look of one of the detected structures. The emergence of thin current sheets can lead to electron scale structures. Within these structures, we see signatures of ion demagnetization, electron jets, electron heating, and agyrotropy suggesting that MMS spacecraft observe reconnection at these scales.
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| 19. |
- Dekki, N, et al.
(författare)
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Type 1 diabetic serum interferes with pancreatic beta-cell Ca2+-handling
- 2007
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Ingår i: Bioscience reports. - : Portland Press Ltd.. - 0144-8463 .- 1573-4935. ; 27:6, s. 321-326
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to clarify the frequency of patients with type 1 diabetes that have serum that increases pancreatic β-cell cytoplasmic free Ca2+ concentration, [Ca2+]i, and if such an effect is also present in serum from first-degree relatives. We also studied a possible link between the serum effect and ethnic background as well as presence of autoantibodies. Sera obtained from three different countries were investigated as follows: 82 Swedish Caucasians with newly diagnosed type 1 diabetes, 56 Americans with different duration of type 1 diabetes, 117 American first-degree relatives of type 1 diabetic patients with a mixed ethnic background and 31 Caucasian Finnish children with newly diagnosed type 1 diabetes. Changes in [Ca2+]i, upon depolarization, were measured in β-cells incubated overnight with sera from type 1 diabetic patients, first-degree relatives or healthy controls. Our data show that there is a group constituting approximately 30% of type 1 diabetic patients of different gender, age, ethnic background and duration of the disease, as well as first-degree relatives of type 1 diabetic patients, that have sera that interfere with pancreatic β-cell Ca2+-handling. This effect on β-cell [Ca2+]i could not be correlated to the presence of autoantibodies. In a defined subgroup of patients with type 1 diabetes and first-degree relatives a defect Ca2+-handling may aggravate development of β-cell destruction.
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| 20. |
- Elimam, A, et al.
(författare)
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Growth hormone treatment downregulates serum leptin levels in children independent of changes in body mass index
- 1999
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Ingår i: Hormone research. - : S. Karger AG. - 0301-0163. ; 52:2, s. 66-72
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Tidskriftsartikel (refereegranskat)abstract
- The changes in serum leptin levels during growth hormone (GH) treatment were studied in 27 children, 17 with GH deficiency (GHD), 10 with idiopathic short stature (ISS), and 9 with Prader-Willi syndrome (PWS). Within 1 month of GH treatment, serum leptin levels decreased by 40% in the GHD children (p < 0.01). There was no significant change in serum leptin level in the children with ISS. In children with PWS, the mean serum leptin level decreased by almost 60% after 3 months of treatment (p < 0.001). Thereafter, no further decline was observed in any of the 3 groups. Changes in body composition became evident first after the 3 months of treatment. In the GHD children, the BMI was unchanged while the mean body fat percentage was 2.7% lower after 1 year of GH treatment (p < 0.05). In the ISS children, neither BMI nor body fat percentage were significantly changed during treatment. The PWS children exhibited a significant decrease in BMI after 6 months of GH treatment without any further change during the remaining period of treatment. In this group, the mean body fat percentage decreased from 42 ± 2.4 to 28 ± 2.2% after treatment (p < 0.001). The finding that the fall in leptin occurs before changes in body composition become detectable suggests a direct effect of GH on leptin production, metabolism, or clearance.
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| 21. |
- Khotyaintsev, Yu, V, et al.
(författare)
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Electron Heating by Debye-Scale Turbulence in Guide-Field Reconnection
- 2020
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Ingår i: Physical Review Letters. - : AMER PHYSICAL SOC. - 0031-9007 .- 1079-7114. ; 124:4
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Tidskriftsartikel (refereegranskat)abstract
- We report electrostatic Debye-scale turbulence developing within the diffusion region of asymmetric magnetopause reconnection with amoderate guide field using observations by the Magnetospheric Multiscale mission. We show that Buneman waves and beam modes cause efficient and fast thermalization of the reconnection electron jet by irreversible phase mixing, during which the jet kinetic energy is transferred into thermal energy. Our results show that the reconnection diffusion region in the presence of a moderate guide field is highly turbulent, and that electrostatic turbulence plays an important role in electron heating.
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| 22. |
- Li, Yu-Xuan, et al.
(författare)
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Quantification of Cold-Ion Beams in a Magnetic Reconnection Jet
- 2021
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Ingår i: Frontiers in Astronomy and Space Sciences. - : Frontiers Media S.A.. - 2296-987X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Cold (few eV) ions of ionospheric origin are widely observed in the lobe region of Earth's magnetotail and can enter the ion jet region after magnetic reconnection is triggered in the magnetotail. Here, we investigate a magnetotail crossing with cold ions in one tailward and two earthward ion jets observed by the Magnetospheric Multiscale (MMS) constellation of spacecraft. Cold ions co-existing with hot plasma-sheet ions form types of ion velocity distribution functions (VDFs) in the three jets. In one earthward jet, MMS observe cold-ion beams with large velocities parallel to the magnetic fields, and we perform quantitative analysis on the ion VDFs in this jet. The cold ions, together with the hot ions, are reconnection outflow ions and are a minor population in terms of number density inside this jet. The average bulk speed of the cold-ion beams is approximately 38% larger than that of the hot plasma-sheet ions. The cold-ion beams inside the explored jet are about one order of magnitude colder than the hot plasma-sheet ions. These cold-ion beams could be accelerated by the Hall electric field in the cold ion diffusion region and the shrinking magnetic field lines through the Fermi effect.
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| 23. |
- Lundgren, Fredrik, et al.
(författare)
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PTFE bypass to below-knee arteries : distal vein collar or not? A prospective randomised multicentre study
- 2010
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Ingår i: European Journal of Vascular and Endovascular Surgery. - : Elsevier BV. - 1078-5884 .- 1532-2165. ; 39:6, s. 747-754
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundPatency and limb salvage after synthetic bypass to the arteries below-knee are inferior to that which can be achieved with autologous vein. Use of a vein collar at the distal anastomosis has been suggested to improve patency and limb salvage, a problem that is analysed in this randomised clinical study.MethodsPatients with critical limb ischaemia undergoing polytetrafluoroethylene (PTFE) bypass to below-knee arteries were randomly either assigned a vein collar or not in two groups – bypass to the popliteal artery below-knee (femoro-popliteal below-knee (FemPopBK)) and more distal bypass (femoro-distal bypass (FemDist)). Follow-up was scheduled until amputation, death or at most 5 years, whichever event occurred first.ResultsIn the FemPopBK and in the FemDist groups, 115/202 and 72/150 were randomised to have a vein collar, respectively. Information was available for 345 of 352 randomised patients (98%).At 3 years, primary patency was 26% (95% confidence interval (CI) 18–38) with a vein collar and 43 (33–58) without a vein collar for femoro-popliteal bypass and 20 (11–38), and 17 (9–33) for femoro-distal bypass, respectively. The corresponding figures for limb salvage were 64 (54–75) and 61 (50–74) for femoro-popliteal bypass, and 59 (46–76) and 44 (32–61) for femoro-distal bypass with and without a vein collar, respectively. Log-rank-test for the whole Kaplan–Meier life table curve showed no statistically significant differences with or without vein collar primary patency: p = 0.0853, p = 0.228; secondary patency: p = 0.317, p = 0.280; limb salvage: p = 0.757, p = 0.187 for FemPopBK and FemDist, respectively. The use of a vein collar did not influence patency or limb salvage.ConclusionThis study failed to show any benefit for vein collar with PTFE bypass to a below-knee artery.
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| 24. |
- Pettersson, Gunilla, et al.
(författare)
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Strong and bulky paperboard plies from low energy CTMP
- 2014
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Ingår i: International Mechanical Pulping Conference, IMPC 2014. - 9780000000002
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Konferensbidrag (refereegranskat)abstract
- A description is given regarding methods used to manufacture strong and bulky sheets from furnishes based on a broad range of surface modified CTMP qualities. Starch and CMC are adsorbed on the fibre surfaces using a multilayer or a MIX concept. It is shown that both the in-plane and out-of-plane strength for the CTMP based sheets after such surface treatment can be more than doubled at a maintained density. This can be utilized to improve bending stiffness or to reduce the basis weight in multi-ply paperboards.
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| 25. |
- Pijnenburg, Yolande A L, et al.
(författare)
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CSF neurofilaments in frontotemporal dementia compared with early onset Alzheimer's disease and controls.
- 2007
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Ingår i: Dementia and Geriatric Cognitive Disorders. - : S. Karger AG. - 1420-8008 .- 1421-9824. ; 23:4, s. 225-30
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Frontotemporal dementia (FTD) is pathologically heterogeneous, sometimes revealing intraneuronal inclusions of neurofilaments. We therefore measured CSF neurofilament profiles in patients with FTD, patients with early onset Alzheimer's disease (EAD) and healthy control subjects to explore the discriminative potential of CSF neurofilaments compared with the existing CSF biomarkers amyloid-beta(1-42), tau and tau phosphorylated at threonine-181. METHODS: CSF levels of light chain, heavy chain and hyperphosphorylated heavy chain neurofilaments (NfL, t-NfH and P-NfH) were compared between 17 subjects with FTD, 20 with EAD and 25 cognitively healthy controls. RESULTS: A subgroup of FTD patients had remarkably high CSF levels of both NfL and NfH. The degree of NfH phosphorylation was increased in FTD compared to both other groups. The levels of CSF NfL were significantly higher in EAD compared to controls. CONCLUSION: Differences in CSF biomarker profiles might reflect differential involvement of neurofilaments and tau in FTD and EAD. The subgroup of FTD patients with high CSF neurofilament levels may have a different neuropathological substrate and future studies addressing this specific issue are needed.
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| 26. |
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| 27. |
- Voros, Z., et al.
(författare)
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MMS Observation of Magnetic Reconnection in the Turbulent Magnetosheath
- 2017
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Ingår i: Journal of Geophysical Research - Space Physics. - : AMER GEOPHYSICAL UNION. - 2169-9380 .- 2169-9402. ; 122:11, s. 11442-11467
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Tidskriftsartikel (refereegranskat)abstract
- In this paper we use the full armament of the MMS (Magnetospheric Multiscale) spacecraft to study magnetic reconnection in the turbulent magnetosheath downstream of a quasi-parallel bow shock. Contrarily to the magnetopause and magnetotail cases, only a few observations of reconnection in the magnetosheath have been reported. The case study in this paper presents, for the first time, both fluid-scale and kinetic-scale signatures of an ongoing reconnection in the turbulent magnetosheath. The spacecraft are crossing the reconnection inflow and outflow regions and the ion diffusion region (IDR). Inside the reconnection outflows D shape ion distributions are observed. Inside the IDR mixing of ion populations, crescent-like velocity distributions and ion accelerations are observed. One of the spacecraft skims the outer region of the electron diffusion region, where parallel electric fields, energy dissipation/conversion, electron pressure tensor agyrotropy, electron temperature anisotropy, and electron accelerations are observed. Some of the difficulties of the observations of magnetic reconnection in turbulent plasma are also outlined.
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| 28. |
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| 29. |
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| 30. |
- Arhammar, C., et al.
(författare)
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A theoretical study of possible point defects incorporated into alpha-alumina deposited by chemical vapor deposition
- 2013
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Ingår i: Theoretical Chemistry accounts. - : Springer Science and Business Media LLC. - 1432-881X .- 1432-2234. ; 133:2, s. 1433-
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Tidskriftsartikel (refereegranskat)abstract
- The energetics and electronic structure of carbon, chlorine, hydrogen, and sulfur in alpha-Al2O3 was investigated by first principles and thermodynamical calculations. These species are present in the gas phase during the synthesis of alpha-Al2O3 by chemical vapor deposition (CVD) but little is known of their solubility in this compound. The heat of formation from standard reference states of the elements varying the chemical potential of each element was calculated. An attempt to model the actual conditions in the CVD process was made, using the species and solid compounds present in a common CVD process as reference states. Our calculations suggest that sulfur from the catalyzing agent H2S will not solve in alpha-Al2O3 during deposition by CVD. It is found that the neutral chlorine and hydrogen interstitial defects display the lowest heat of formation, 281 and 280 kJ/mol, respectively, at the modeled CVD conditions. This energy is too high in order for neutral defects to form during CVD of alpha-Al2O3 at any significant amounts. The charged defects and their compensation were studied. Carbon substituting oxygen is found to be energetically favored under the modeled CVD conditions, considering carbon dioxide as competing species to solid solubility in alpha-Al2O3 at an energy of -128 kJ/mol. However, care needs to be taken when choosing the possible competing carbon-containing phases. Compensation of carbon substituting for oxygen by oxygen vacancies takes place at 110 kJ/mol from standard reference states, graphite, fcc-Al and O-2. The carbon solubility in Al2O3 is difficult to measure with standard analysis techniques such as X-ray diffraction and energy dispersive X-ray spectroscopy, but several stable compounds in the Al-C-O are available in the literature.
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| 31. |
- Belch, Jill J. F., et al.
(författare)
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Results of the randomized, placebo-controlled clopidogrel and acetylsalicylic acid in bypass surgery for peripheral arterial disease (CASPAR) trial
- 2010
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Ingår i: Journal of vascular surgery : official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter. - : Elsevier BV. - 0741-5214. ; 52:4, s. 825-833, 833.e1-2
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Tidskriftsartikel (refereegranskat)abstract
- The combination of clopidogrel plus ASA did not improve limb or systemic outcomes in the overall population of PAD patients requiring below-knee bypass grafting. Subgroup analysis suggests that clopidogrel plus ASA confers benefit in patients receiving prosthetic grafts without significantly increasing major bleeding risk.
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| 32. |
- Benterud, T, et al.
(författare)
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N-Acetylcysteine Amide Exerts Possible Neuroprotective Effects in Newborn Pigs after Perinatal Asphyxia
- 2017
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Ingår i: Neonatology. - : S. Karger AG. - 1661-7819 .- 1661-7800. ; 111:1, s. 12-21
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Tidskriftsartikel (refereegranskat)abstract
- <b><i>Background:</i></b> Perinatal asphyxia and ensuing reoxygenation change the antioxidant capacity of cells and organs. <b><i>Objectives:</i></b> To analyze the neuroprotective effect of the antioxidant N-acetylcysteine amide (NACA) after perinatal hypoxia-reoxygenation with an emphasis on proinflammatory cytokines and the transcription factor NF-κB in the prefrontal cortex of neonatal pigs. <b><i>Methods:</i></b> Twenty-nine newborn pigs, aged 12-36 h, were subjected to global hypoxia and hypercapnia. One sham-operated group (n = 5) and 2 experimental groups (n = 12) were exposed to 8% oxygen, until the base excess was -20 mmol/l or the mean arterial blood pressure fell to <20 mm Hg (asphyxia with NACA or saline). The pigs were observed for 9.5 h after hypoxia. Samples of prefrontal cortex and plasma were analyzed. <b><i>Results:</i></b> Cortex: there was no significant difference in mRNA expression between the intervention groups regarding IL-1β, IL6, TNFα, MMP2, MMP9 or IL18. Pigs exposed to hypoxia-reoxygenation and treatment with NACA (NACA-pigs) had a significantly lower protein concentration of IL-1β than pigs treated with saline (placebo controls), i.e. 8.8 ± 3.9 versus 16.8 ± 10.5 pg/mg protein (p = 0.02). The activation of the transcription factor NF-κB (measured as the fold-change of phosphorylated p65<sup>Ser 536</sup>), was reduced in the NACA-pigs when compared to the placebo controls (5.2 ± 4.3 vs. 16.0 ± 13.5; p = 0.02). No difference between the intervention groups regarding brain histopathology or in the levels of 8-oxoguanine measured in the prefrontal cortex were observed. Plasma: the NACA-pigs had a stronger reduction of TNFα in the first 30 min following asphyxia compared with the placebo controls, i.e. 36 (30-44) versus 24 (14-32)% (p = 0.01). <b><i>Conclusion:</i></b> The reduced levels of the pivotal inflammatory markers IL-1β and TNFα and the transcription factor NF-κB may indicate that NACA has possible neuroprotective effects after perinatal asphyxia.
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| 33. |
- Berger, J. S., et al.
(författare)
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Design and rationale for the Effects of Ticagrelor and Clopidogrel in Patients with Peripheral Artery Disease (EUCLID) trial
- 2016
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Ingår i: American Heart Journal. - : Elsevier BV. - 0002-8703. ; 175, s. 86-93
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Tidskriftsartikel (refereegranskat)abstract
- Background Despite overwhelming data demonstrating the efficacy of antiplatelet therapy in heart disease and stroke, data in peripheral artery disease (PAD) are less compelling. Aspirin has modest evidence supporting a reduction in cardiovascular events in patients with PAD, whereas clopidogrel monotherapy may be more effective in PAD. Ticagrelor, a potent, reversibly binding P2Y(12) receptor antagonist, is beneficial in patients with acute coronary syndrome and prior myocardial infarction. The EUCLID trial is designed to address the need for effective antiplatelet therapy in PAD to decrease the risk of cardiovascular events. Study design EUCLID is a randomized, double-blind, parallel-group, multinational clinical trial designed to evaluate the efficacy and safety of ticagrelor compared with clopidogrel for the prevention of major adverse cardiovascular events in subjects with symptomatic PAD. Subjects with established PAD will be randomized in a 1: 1 fashion to ticagrelor 90 mg twice daily or clopidogrel 75 mg daily. The primary end point is a composite of cardiovascular death, myocardial infarction, or ischemic stroke. Other end points address limb events including acute leg ischemia, need for revascularization, disease progression by ankle-brachial index, and quality of life. The primary safety objective is Thrombolysis in Myocardial Infarction-defined major bleeding. Recruitment began in December 2012 and was completed in March 2014; 13,887 patients were randomized. The trial will continue until at least 1,364 adjudicated primary end points occur. Conclusions The EUCLID study is investigating whether treatment with ticagrelor versus clopidogrel, given as antiplatelet monotherapy, will reduce the incidence of cardiovascular and limb-specific events in patients with symptomatic PAD.
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| 34. |
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| 35. |
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| 36. |
- Danielsson, Gudmundur, et al.
(författare)
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A randomised controlled trial of micronised purified flavonoid fraction vs placebo in patients with chronic venous disease
- 2002
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Ingår i: European Journal of Vascular and Endovascular Surgery. - : Elsevier BV. - 1532-2165 .- 1078-5884. ; 23:1, s. 73-76
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Tidskriftsartikel (refereegranskat)abstract
- Objective: to evaluate the efficacy of a micromised purified flavonoid fraction (MPFF) in the treatment of chronic venous disease (CVD). Design: prospective doable blind, randomised, control shady. Patients and methods: one hundred and one patients with symptomatic CVD were randomly allocated to treatment for 60 days with either MPFF (51 patients) or placebo (50 patients) 500 mg twice daily. There were 28 men and 73 women, aged 22-65 years (mean age 48 years). No difference regarding age, gender, clinical class or duration of symptoms was recorded between the treatment and placebo groups. A global score for evaluation of symptoms was used. Patients were investigated with plethysmography (foot-volumetry) and duplex-ultrasonography before and after the treatment period. For statistical comparison Cochran-Mantel-Haenszel test, two-sided Student t-test and covariance analysis were used and p<0.05 was regarded significant. Results: improvement of the global score of symptoms was reported by 21 patients in the MPFF group and by 16 in the placebo group (N.S.). For the whole groups, no significant differences were recorded before and after treatment regarding foot-volumetric or ultrasonography parameters. On the other hand, in patients with edema (20 in the MPFF group, 23 in tire placebo group) ultrasonographic reflux time was significantly reduced for those in the treatment group (p=0.03). This finding did not correlate to clinical symptoms. Conclusion: in this study, MPFF dirt trot change the symptoms of CVD, except might cramps. A secondary finding was reduced reflux times in patients with oedema, although no ultrasonographic or foot-volumetric parameters changed significantly for the whole group. The role of MPFF in treatment of patients with CVD needs to be further analysed in a large population.
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| 37. |
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| 38. |
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| 39. |
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| 40. |
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| 41. |
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| 42. |
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| 43. |
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| 44. |
- Eliman, A., et al.
(författare)
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Totalparenteral nutrition after surgery rapidly increases serum leptin levels
- 2001
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Ingår i: European Journal of Endocrinology. - Bristol, NQ, USA : Bioscientifica. - 0804-4643 .- 1479-683X. ; 144:2, s. 123-128
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: In humans, leptin is regulated by long-term changes in energy intake. However, short-term regulation of serum leptin by nutrients has been difficult to show. The aim of this study was to investigate whether short periods of fasting and stress sensitise the leptin response to nutrients.Subjects and experimental protocol: Fourteen patients of normal weight undergoing elective open cholecystectomy were randomised into two groups. One group received saline infusion during surgery and for 24 h postoperatively. The other group also received saline during the surgical procedure, but total parenteral (TPN) was started immediately after surgery. Blood samples were drawn before as well as 2, 4, 8, 16, and 24 h after the start of surgery to determine the serum levels of leptin and other hormones.Results: Postoperative TPN induced a significant rise in serum leptin within 6 h, reaching a more than fourfold increase within 14 h (P < 0.001). Serum glucose and insulin levels increased within 2 h. Growth hormone and IGF-1 serum levels also increased significantly in the group receiving TPN. Serum cortisol levels increased postoperatively in both groups, which may explain why no significant reduction in serum leptin was observed in the group receiving saline. Free tri-iodothyronine (T3) decreased in both groups, while catecholamines were similar in the groups.Conclusion: During fasting and surgical stress, nutrients rapidly increased the serum leptin levels in humans in a manner similar to that previously reported in rodents. This may be mediated by increases in serum glucose, insulin and cortisol.
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| 45. |
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| 46. |
- Franco, Irene, et al.
(författare)
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Whole genome DNA sequencing provides an atlas of somatic mutagenesis in healthy human cells and identifies a tumor-prone cell type
- 2019
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Ingår i: Genome Biology. - : Springer Science and Business Media LLC. - 1465-6906 .- 1474-760X. ; 20:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: The lifelong accumulation of somatic mutations underlies age-related phenotypes and cancer. Mutagenic forces are thought to shape the genome of aging cells in a tissue-specific way. Whole genome analyses of somatic mutation patterns, based on both types and genomic distribution of variants, can shed light on specific processes active in different human tissues and their effect on the transition to cancer. Results: To analyze somatic mutation patterns, we compile a comprehensive genetic atlas of somatic mutations in healthy human cells. High-confidence variants are obtained from newly generated and publicly available whole genome DNA sequencing data from single non-cancer cells, clonally expanded in vitro. To enable a well-controlled comparison of different cell types, we obtain single genome data (92% mean coverage) from multi-organ biopsies from the same donors. These data show multiple cell types that are protected from mutagens and display a stereotyped mutation profile, despite their origin from different tissues. Conversely, the same tissue harbors cells with distinct mutation profiles associated to different differentiation states. Analyses of mutation rate in the coding and non-coding portions of the genome identify a cell type bearing a unique mutation pattern characterized by mutation enrichment in active chromatin, regulatory, and transcribed regions. Conclusions: Our analysis of normal cells from healthy donors identifies a somatic mutation landscape that enhances the risk of tumor transformation in a specific cell population from the kidney proximal tubule. This unique pattern is characterized by high rate of mutation accumulation during adult life and specific targeting of expressed genes and regulatory regions.
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| 47. |
- Fuselier, S. A., et al.
(författare)
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Large-scale characteristics of reconnection diffusion regions and associated magnetopause crossings observed by MMS
- 2017
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Ingår i: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 122:5, s. 5466-5486
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Tidskriftsartikel (refereegranskat)abstract
- The Magnetospheric Multiscale (MMS) mission was designed to make observations in the very small electron diffusion region (EDR), where magnetic reconnection takes place. From a data set of over 4500 magnetopause crossings obtained in the first phase of the mission, MMS had encounters near or within 12 EDRs. These 12 events and associated magnetopause crossings are considered as a group to determine if they span the widest possible range of external and internal conditions (i.e., in the solar wind and magnetosphere). In addition, observations from MMS are used to determine if there are multiple X-lines present and also to provide information on X-line location relative to the spacecraft. These 12 events represent nearly the widest possible range of conditions at the dayside magnetopause. They occur over a wide range of local times and magnetic shear angles between the magnetosheath and magnetospheric magnetic fields. Most show evidence for multiple reconnection sites.
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| 48. |
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| 49. |
- Galli, J, et al.
(författare)
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Pathophysiological and genetic characterization of the major diabetes locus in GK rats
- 1999
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 48:12, s. 2463-2470
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Tidskriftsartikel (refereegranskat)abstract
- Genetic studies of the type 2 diabetes-like GK rat have revealed several susceptibility loci for the compound diabetes phenotype. Congenic strains were established for Niddm1, the major quantitative trait locus (QTL) for postprandial glucose levels, by transfer of GK alleles onto the genome of the normoglycemic F344 rat. Despite the polygenic nature of diabetes in GK, the locus-specific diabetes phenotype was retained in the congenic strain Niddmla, containing a GK-derived genomic fragment of 52 cM from the Niddm1 locus. Furthermore, Niddm1 was divided into two non-overlapping loci, physically separated in the two congenic strains Niddmlb and Niddm1i with distinct metabolic phenotypes. Both strains displayed postprandial hyperglycemia and reduced insulin action in isolated adipose cells. Furthermore, Niddm1i already exhibits a pronounced in vivo insulin secretion defect at 65 days, while Niddm1b develops a relative insulin secretory defect at 95 days. This suggests that Niddm1i impairs mechanisms common to insulin secretion in pancreatic B-cells and insulin action in adipocytes. Niddm1b rats show signs of increasing insulin resistance with age associated with obesity, hyperinsulinemia, and dyslipidemia. Moreover, the data indicated nonallelic interaction (epistasis) between Niddm1b and Niddm1i on the postprandial glucose levels. These data emphasize the pathophysiological complexity of diabetes, even within an apparently single QTL, and demonstrate the potential of the GK model in transforming the multifactorial diabetes phenotype into single traits, suitable for positional cloning.
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| 50. |
- Gericke, Martin, et al.
(författare)
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The European Polysaccharide Network of Excellence (EPNOE) research roadmap 2040: Advanced strategies for exploiting the vast potential of polysaccharides as renewable bioresources
- 2024
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Ingår i: Carbohydrate Polymers. - : Elsevier BV. - 0144-8617 .- 1879-1344. ; 326
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Tidskriftsartikel (refereegranskat)abstract
- Polysaccharides are among the most abundant bioresources on earth and consequently need to play a pivotal role when addressing existential scientific challenges like climate change and the shift from fossil-based to sustainable biobased materials. The Research Roadmap 2040 of the European Polysaccharide Network of Excellence (EPNOE) provides an expert's view on how future research and development strategies need to evolve to fully exploit the vast potential of polysaccharides as renewable bioresources. It is addressed to academic researchers, companies, as well as policymakers and covers five strategic areas that are of great importance in the context of polysaccharide related research: (I) Materials & Engineering, (II) Food & Nutrition, (III) Biomedical Applications, (IV) Chemistry, Biology & Physics, and (V) Skills & Education. Each section summarizes the state of research, identifies challenges that are currently faced, project achievements and developments that are expected in the upcoming 20 years, and finally provides outlines on how future research activities need to evolve.
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