| 1. |
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| 2. |
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| 3. |
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| 4. |
- Aad, G, et al.
(författare)
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Search for Higgs Boson Pair Production in the γγbb[over ¯] Final State Using pp Collision Data at sqrt[s]=8 TeV from the ATLAS Detector.
- 2015
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Ingår i: Physical Review Letters. - 1079-7114. ; 114:8
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Tidskriftsartikel (refereegranskat)abstract
- Searches are performed for resonant and nonresonant Higgs boson pair production in the γγbb[over ¯] final state using 20 fb^{-1} of proton-proton collisions at a center-of-mass energy of 8 TeV recorded with the ATLAS detector at the CERN Large Hadron Collider. A 95% confidence level upper limit on the cross section times branching ratio of nonresonant production is set at 2.2 pb, while the expected limit is 1.0 pb. The difference derives from a modest excess of events, corresponding to 2.4 standard deviations from the background-only hypothesis. The limit observed in the search for a narrow X→hh resonance ranges between 0.7 and 3.5 pb as a function of the resonance mass.
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| 5. |
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| 6. |
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| 7. |
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| 8. |
- Kattge, Jens, et al.
(författare)
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TRY plant trait database - enhanced coverage and open access
- 2020
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Ingår i: Global Change Biology. - : Wiley-Blackwell. - 1354-1013 .- 1365-2486. ; 26:1, s. 119-188
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Tidskriftsartikel (refereegranskat)abstract
- Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.
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| 9. |
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| 10. |
- Aad, G, et al.
(författare)
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Determination of spin and parity of the Higgs boson in the [Formula: see text] decay channel with the ATLAS detector.
- 2015
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 75:5
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Tidskriftsartikel (refereegranskat)abstract
- Studies of the spin and parity quantum numbers of the Higgs boson in the [Formula: see text] final state are presented, based on proton-proton collision data collected by the ATLAS detector at the Large Hadron Collider, corresponding to an integrated luminosity of 20.3 fb[Formula: see text] at a centre-of-mass energy of [Formula: see text] TeV. The Standard Model spin-parity [Formula: see text] hypothesis is compared with alternative hypotheses for both spin and CP. The case where the observed resonance is a mixture of the Standard-Model-like Higgs boson and CP-even ([Formula: see text]) or CP-odd ([Formula: see text]) Higgs boson in scenarios beyond the Standard Model is also studied. The data are found to be consistent with the Standard Model prediction and limits are placed on alternative spin and CP hypotheses, including CP mixing in different scenarios.
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| 11. |
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| 12. |
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| 13. |
- Aad, G, et al.
(författare)
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Measurements of fiducial cross-sections for [Formula: see text] production with one or two additional b-jets in pp collisions at [Formula: see text]=8 TeV using the ATLAS detector.
- 2016
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 76
-
Tidskriftsartikel (refereegranskat)abstract
- Fiducial cross-sections for [Formula: see text] production with one or two additional b-jets are reported, using an integrated luminosity of 20.3 fb[Formula: see text] of proton-proton collisions at a centre-of-mass energy of 8 TeV at the Large Hadron Collider, collected with the ATLAS detector. The cross-section times branching ratio for [Formula: see text] events with at least one additional b-jet is measured to be 950 [Formula: see text] 70 (stat.) [Formula: see text] (syst.) fb in the lepton-plus-jets channel and 50 [Formula: see text] 10 (stat.) [Formula: see text] (syst.) fb in the [Formula: see text] channel. The cross-section times branching ratio for events with at least two additional b-jets is measured to be 19.3 [Formula: see text] 3.5 (stat.) [Formula: see text] 5.7 (syst.) fb in the dilepton channel ([Formula: see text], [Formula: see text], and ee) using a method based on tight selection criteria, and 13.5 [Formula: see text] 3.3 (stat.) [Formula: see text] 3.6 (syst.) fb using a looser selection that allows the background normalisation to be extracted from data. The latter method also measures a value of 1.30 [Formula: see text] 0.33 (stat.) [Formula: see text] 0.28 (syst.)% for the ratio of [Formula: see text] production with two additional b-jets to [Formula: see text] production with any two additional jets. All measurements are in good agreement with recent theory predictions.
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| 14. |
- Aad, G, et al.
(författare)
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Measurements of the Higgs boson production and decay rates and coupling strengths using pp collision data at [Formula: see text] and 8 TeV in the ATLAS experiment.
- 2016
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 76
-
Tidskriftsartikel (refereegranskat)abstract
- Combined analyses of the Higgs boson production and decay rates as well as its coupling strengths to vector bosons and fermions are presented. The combinations include the results of the analyses of the [Formula: see text] and [Formula: see text] decay modes, and the constraints on the associated production with a pair of top quarks and on the off-shell coupling strengths of the Higgs boson. The results are based on the LHC proton-proton collision datasets, with integrated luminosities of up to 4.7 [Formula: see text] at [Formula: see text] TeV and 20.3 [Formula: see text] at [Formula: see text] TeV, recorded by the ATLAS detector in 2011 and 2012. Combining all production modes and decay channels, the measured signal yield, normalised to the Standard Model expectation, is [Formula: see text]. The observed Higgs boson production and decay rates are interpreted in a leading-order coupling framework, exploring a wide range of benchmark coupling models both with and without assumptions on the Higgs boson width and on the Standard Model particle content in loop processes. The data are found to be compatible with the Standard Model expectations for a Higgs boson at a mass of 125.36 GeV for all models considered.
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| 15. |
- Aad, G, et al.
(författare)
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Observation and measurements of the production of prompt and non-prompt [Formula: see text] mesons in association with a [Formula: see text] boson in [Formula: see text] collisions at [Formula: see text] with the ATLAS detector.
- 2015
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 75:5
-
Tidskriftsartikel (refereegranskat)abstract
- The production of a [Formula: see text] boson in association with a [Formula: see text] meson in proton-proton collisions probes the production mechanisms of quarkonium and heavy flavour in association with vector bosons, and allows studies of multiple parton scattering. Using [Formula: see text] of data collected with the ATLAS experiment at the LHC in [Formula: see text] collisions at [Formula: see text], the first measurement of associated [Formula: see text] production is presented for both prompt and non-prompt [Formula: see text] production, with both signatures having a significance in excess of [Formula: see text]. The inclusive production cross-sections for [Formula: see text] boson production (analysed in [Formula: see text] or [Formula: see text] decay modes) in association with prompt and non-prompt [Formula: see text] are measured relative to the inclusive production rate of [Formula: see text] bosons in the same fiducial volume to be [Formula: see text] and [Formula: see text] respectively. Normalised differential production cross-section ratios are also determined as a function of the [Formula: see text] transverse momentum. The fraction of signal events arising from single and double parton scattering is estimated, and a lower limit of [Formula: see text] at [Formula: see text] confidence level is placed on the effective cross-section regulating double parton interactions.
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| 16. |
- Aad, G, et al.
(författare)
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Search for a new resonance decaying to a W or Z boson and a Higgs boson in the [Formula: see text] final states with the ATLAS detector.
- 2015
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 75:6
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Tidskriftsartikel (refereegranskat)abstract
- A search for a new resonance decaying to a W or Z boson and a Higgs boson in the [Formula: see text] final states is performed using 20.3 fb[Formula: see text] of pp collision data recorded at [Formula: see text] 8 TeV with the ATLAS detector at the Large Hadron Collider. The search is conducted by examining the WH / ZH invariant mass distribution for a localized excess. No significant deviation from the Standard Model background prediction is observed. The results are interpreted in terms of constraints on the Minimal Walking Technicolor model and on a simplified approach based on a phenomenological Lagrangian of Heavy Vector Triplets.
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| 17. |
- Aad, G, et al.
(författare)
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Search for direct pair production of a chargino and a neutralino decaying to the 125 GeV Higgs boson in [Formula: see text] TeV [Formula: see text] collisions with the ATLAS detector.
- 2015
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 75:5
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Tidskriftsartikel (refereegranskat)abstract
- A search is presented for the direct pair production of a chargino and a neutralino [Formula: see text], where the chargino decays to the lightest neutralino and the [Formula: see text] boson, [Formula: see text], while the neutralino decays to the lightest neutralino and the 125 GeV Higgs boson, [Formula: see text]. The final states considered for the search have large missing transverse momentum, an isolated electron or muon, and one of the following: either two jets identified as originating from bottom quarks, or two photons, or a second electron or muon with the same electric charge. The analysis is based on 20.3 [Formula: see text] of [Formula: see text] proton-proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with the Standard Model expectations, and limits are set in the context of a simplified supersymmetric model.
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| 18. |
- Aad, G, et al.
(författare)
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Search for heavy long-lived multi-charged particles in pp collisions at [Formula: see text] TeV using the ATLAS detector.
- 2015
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 75:8
-
Tidskriftsartikel (refereegranskat)abstract
- A search for heavy long-lived multi-charged particles is performed using the ATLAS detector at the LHC. Data collected in 2012 at [Formula: see text] TeV from pp collisions corresponding to an integrated luminosity of 20.3 fb[Formula: see text]are examined. Particles producing anomalously high ionisation, consistent with long-lived massive particles with electric charges from [Formula: see text] to [Formula: see text] are searched for. No signal candidate events are observed, and 95 % confidence level cross-section upper limits are interpreted as lower mass limits for a Drell-Yan production model. The mass limits range between 660 and 785 GeV.
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| 19. |
- Aad, G, et al.
(författare)
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Search for Higgs boson pair production in the [Formula: see text] final state from pp collisions at [Formula: see text] TeVwith the ATLAS detector.
- 2015
-
Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 75:9
-
Tidskriftsartikel (refereegranskat)abstract
- A search for Higgs boson pair production [Formula: see text] is performed with 19.5 fb[Formula: see text] of proton-proton collision data at [Formula: see text] TeV, which were recorded by the ATLAS detector at the Large Hadron Collider in 2012. The decay products of each Higgs boson are reconstructed as a high-momentum [Formula: see text] system with either a pair of small-radius jets or a single large-radius jet, the latter exploiting jet substructure techniques and associated b-tagged track-jets. No evidence for resonant or non-resonant Higgs boson pair production is observed. The data are interpreted in the context of the Randall-Sundrum model with a warped extra dimension as well as the two-Higgs-doublet model. An upper limit on the cross-section for [Formula: see text] of 3.2 (2.3) fb is set for a Kaluza-Klein graviton [Formula: see text] mass of 1.0 (1.5) TeV, at the 95 % confidence level. The search for non-resonant Standard Model hh production sets an observed 95 % confidence level upper limit on the production cross-section [Formula: see text] of 202 fb, compared to a Standard Model prediction of [Formula: see text] fb.
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| 20. |
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| 21. |
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| 22. |
- Aad, G, et al.
(författare)
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Search for production of [Formula: see text] resonances decaying to a lepton, neutrino and jets in [Formula: see text] collisions at [Formula: see text] TeV with the ATLAS detector.
- 2015
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 75:5
-
Tidskriftsartikel (refereegranskat)abstract
- A search is presented for narrow diboson resonances decaying to [Formula: see text] or [Formula: see text] in the final state where one [Formula: see text] boson decays leptonically (to an electron or a muon plus a neutrino) and the other [Formula: see text] boson decays hadronically. The analysis is performed using an integrated luminosity of 20.3 fb[Formula: see text] of [Formula: see text] collisions at [Formula: see text] TeV collected by the ATLAS detector at the large hadron collider. No evidence for resonant diboson production is observed, and resonance masses below 700 and 1490 GeV are excluded at 95 % confidence level for the spin-2 Randall-Sundrum bulk graviton [Formula: see text] with coupling constant of 1.0 and the extended gauge model [Formula: see text] boson respectively.
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| 23. |
- Aad, G, et al.
(författare)
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Searches for scalar leptoquarks in pp collisions at [Formula: see text] = 8 TeV with the ATLAS detector.
- 2016
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 76
-
Tidskriftsartikel (refereegranskat)abstract
- Searches for pair-produced scalar leptoquarks are performed using 20 fb[Formula: see text] of proton-proton collision data provided by the LHC and recorded by the ATLAS detector at [Formula: see text] TeV. Events with two electrons (muons) and two or more jets in the final state are used to search for first (second)-generation leptoquarks. The results from two previously published ATLAS analyses are interpreted in terms of third-generation leptoquarks decaying to [Formula: see text] and [Formula: see text] final states. No statistically significant excess above the Standard Model expectation is observed in any channel and scalar leptoquarks are excluded at 95 % CL with masses up to [Formula: see text] 1050 GeV for first-generation leptoquarks, [Formula: see text] 1000 GeV for second-generation leptoquarks, [Formula: see text] 625 GeV for third-generation leptoquarks in the [Formula: see text] channel, and 200 [Formula: see text] 640 GeV in the [Formula: see text] channel.
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| 24. |
- Aad, G, et al.
(författare)
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Study of the [Formula: see text] and [Formula: see text] decays with the ATLAS detector.
- 2016
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 76
-
Tidskriftsartikel (refereegranskat)abstract
- The decays [Formula: see text] and [Formula: see text] are studied with the ATLAS detector at the LHC using a dataset corresponding to integrated luminosities of 4.9 and 20.6 fb[Formula: see text] of pp collisions collected at centre-of-mass energies [Formula: see text] TeV and 8 TeV, respectively. Signal candidates are identified through [Formula: see text] and [Formula: see text] decays. With a two-dimensional likelihood fit involving the [Formula: see text] reconstructed invariant mass and an angle between the [Formula: see text] and [Formula: see text] candidate momenta in the muon pair rest frame, the yields of [Formula: see text] and [Formula: see text], and the transverse polarisation fraction in [Formula: see text] decay are measured. The transverse polarisation fraction is determined to be [Formula: see text], and the derived ratio of the branching fractions of the two modes is [Formula: see text], where the first error is statistical and the second is systematic. Finally, a sample of [Formula: see text] decays is used to derive the ratios of branching fractions [Formula: see text] and [Formula: see text], where the third error corresponds to the uncertainty of the branching fraction of [Formula: see text] decay. The available theoretical predictions are generally consistent with the measurement.
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| 25. |
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| 26. |
- Abramavicius, Vytautas, et al.
(författare)
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Carrier motion in as-spun and annealed P3HT:PCBM blends revealed by ultrafast optical electric field probing and Monte Carlo simulations
- 2014
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Ingår i: Physical Chemistry Chemical Physics. - : Royal Society of Chemistry (RSC). - 1463-9084 .- 1463-9076. ; 16:6, s. 2686-2692
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Tidskriftsartikel (refereegranskat)abstract
- Charge transport dynamics in solar cell devices based on as-spun and annealed P3HT:PCBM films are compared using ultrafast time-resolved optical probing of the electric field by means of field-induced second harmonic generation. The results show that charge carriers drift about twice as far during the first 3 ns after photogeneration in a device where the active layer has been thermally annealed. The carrier dynamics were modelled using Monte-Carlo simulations and good agreement between experimental and simulated drift dynamics was obtained using identical model parameters for both cells, but with different average PCBM and polymer domain sizes. The calculations suggest that small domain sizes in as-spun samples limit the carrier separation distance disabling their escape from geminate recombination.
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| 27. |
- Almora, Osbel, et al.
(författare)
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Device Performance of Emerging Photovoltaic Materials (Version 1)
- 2020
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Ingår i: Advanced Energy Materials. - : Wiley. - 1614-6832 .- 1614-6840. ; 11:11
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Tidskriftsartikel (refereegranskat)abstract
- Emerging photovoltaics (PVs) focus on a variety of applications complementing large scale electricity generation. Organic, dye-sensitized, and some perovskite solar cells are considered in building integration, greenhouses, wearable, and indoor applications, thereby motivating research on flexible, transparent, semitransparent, and multi-junction PVs. Nevertheless, it can be very time consuming to find or develop an up-to-date overview of the state-of-the-art performance for these systems and applications. Two important resources for recording research cells efficiencies are the National Renewable Energy Laboratory chart and the efficiency tables compiled biannually by Martin Green and colleagues. Both publications provide an effective coverage over the established technologies, bridging research and industry. An alternative approach is proposed here summarizing the best reports in the diverse research subjects for emerging PVs. Best performance parameters are provided as a function of the photovoltaic bandgap energy for each technology and application, and are put into perspective using, e.g., the Shockley–Queisser limit. In all cases, the reported data correspond to published and/or properly described certified results, with enough details provided for prospective data reproduction. Additionally, the stability test energy yield is included as an analysis parameter among state-of-the-art emerging PVs.
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| 28. |
- Ambrose, Aimee, et al.
(författare)
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Histories of heating: looking back, moving forwards
- 2024
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Ingår i: Post-Carbon Inclusion : Transitions Built on Justice - Transitions Built on Justice. - 9781529229448 - 9781529229479 - 9781529229431 ; , s. 36-52
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Bokkapitel (refereegranskat)
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| 29. |
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| 30. |
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| 31. |
- Goldstone, J. V., et al.
(författare)
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Cytochrome P450 1D1 : A novel CYP1A-related gene that is not transcriptionally activated by PCB126 or TCDD
- 2009
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Ingår i: Archives of Biochemistry and Biophysics. - Amsterdam : Elsevier inc.. - 0003-9861 .- 1096-0384. ; 482:1-2, s. 7-16
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Tidskriftsartikel (refereegranskat)abstract
- Enzymes in the cytochrome P450 1 family oxidize many common environmental toxicants. We identified a new CYP1, termed CYP1D1, in zebrafish. Phylogenetically, CYP1D1 is paralogous to CYP1A and the two share 45% amino acid identity and similar gene structure. In adult zebrafish, CYP1D1 is most highlyexpressed in liver and is relatively highly expressed in brain. CYP1D1 transcript levels were higher at 9 h post-fertilization than at later developmental times. Treatment of zebrafish with potent aryl hydrocarbon receptor (AHR) agonists (3,3',4,4',5-pentachlorobiphenyl or 2,3,7,8-tetrachlorodibenzo-p-dioxin) did not induce CYP1D1 transcript expression. Morpholino oligonucleotide knockdown of AHR2, which mediates induction of other CYP1s, did not affect CYP1D1 expression. Zebrafish CYP1D1 heterologously expressed in yeast exhibited ethoxyresorufin- and methoxyresorufin-O-dealkylase activities. Antibodies against a CYP1D1 peptide specifically detected a single electrophoretically-resolved protein band in zebrafish liver microsomes, distinct from CYP1A. CYP1D1 in zebrafish is a CYP1A-like gene that could have metabolic functions targeting endogenous compounds.
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| 32. |
- Henricson, Sofie, et al.
(författare)
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You and I in Sweden-Swedish and Finland-Swedish supervision meetings
- 2015
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Ingår i: Pluricentric languages. - Frankfurt am Main : Peter Lang Publishing Group. - 9783631664339 ; , s. 127-139
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Bokkapitel (refereegranskat)abstract
- This paper presents a study of pronouns used in Sweden-Swedish and Finland-Swedish supervision meetings. In both countries, supervisors use similar sets of pronouns when commenting on an academic essay written by a student. Often, the supervisor addresses the student directly, e.g. but you could write x, or uses an indefinite pronoun, e.g. perhaps one could simply write x. Sometimes, the supervisor makes suggestions while referring to herself as a writer, e.g. I would write x. The supervisor may also use an inclusive we-authorship, e.g. well we cannot write x. This use of we is predominantly found in the Sweden-Swedish data. In relation to politeness strategies, our analysis indicates that pronouns appear in a more direct and clear-cut way (cf. respect strategies) in Finland-Swedish, and with a stronger focus on creating common ground and fostering group membership (cf. solidarity strategies) in Sweden-Swedish. Throughout, we point to differences and similarities between the dominant and the non-dominant variety of Swedish.
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| 33. |
- Huyghe, Jeroen R., et al.
(författare)
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Discovery of common and rare genetic risk variants for colorectal cancer
- 2019
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Ingår i: Nature Genetics. - : Nature Publishing Group. - 1061-4036 .- 1546-1718. ; 51:1, s. 76-
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Tidskriftsartikel (refereegranskat)abstract
- To further dissect the genetic architecture of colorectal cancer (CRC), we performed whole-genome sequencing of 1,439 cases and 720 controls, imputed discovered sequence variants and Haplotype Reference Consortium panel variants into genome-wide association study data, and tested for association in 34,869 cases and 29,051 controls. Findings were followed up in an additional 23,262 cases and 38,296 controls. We discovered a strongly protective 0.3% frequency variant signal at CHD1. In a combined meta-analysis of 125,478 individuals, we identified 40 new independent signals at P < 5 x 10(-8), bringing the number of known independent signals for CRC to similar to 100. New signals implicate lower-frequency variants, Kruppel-like factors, Hedgehog signaling, Hippo-YAP signaling, long noncoding RNAs and somatic drivers, and support a role for immune function. Heritability analyses suggest that CRC risk is highly polygenic, and larger, more comprehensive studies enabling rare variant analysis will improve understanding of biology underlying this risk and influence personalized screening strategies and drug development.
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| 34. |
- Jung, Christian, et al.
(författare)
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A comparison of very old patients admitted to intensive care unit after acute versus elective surgery or intervention
- 2019
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Ingår i: Journal of critical care. - : W B SAUNDERS CO-ELSEVIER INC. - 0883-9441 .- 1557-8615. ; 52, s. 141-148
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Tidskriftsartikel (refereegranskat)abstract
- Background: We aimed to evaluate differences in outcome between patients admitted to intensive care unit (ICU) after elective versus acute surgery in a multinational cohort of very old patients (80 years; VIP). Predictors of mortality, with special emphasis on frailty, were assessed.Methods: In total, 5063 VIPs were induded in this analysis, 922 were admitted after elective surgery or intervention, 4141 acutely, with 402 after acute surgery. Differences were calculated using Mann-Whitney-U test and Wilcoxon test. Univariate and multivariable logistic regression were used to assess associations with mortality.Results: Compared patients admitted after acute surgery, patients admitted after elective surgery suffered less often from frailty as defined as CFS (28% vs 46%; p < 0.001), evidenced lower SOFA scores (4 +/- 5 vs 7 +/- 7; p < 0.001). Presence of frailty (CFS >4) was associated with significantly increased mortality both in elective surgery patients (7% vs 12%; p = 0.01), in acute surgery (7% vs 12%; p = 0.02).Conclusions: VIPs admitted to ICU after elective surgery evidenced favorable outcome over patients after acute surgery even after correction for relevant confounders. Frailty might be used to guide clinicians in risk stratification in both patients admitted after elective and acute surgery.
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| 35. |
- Kirkpatrick, James, et al.
(författare)
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Ultrafast Transient Optical Studies of Charge Pair Generation and Recombination in Poly-3-Hexylthiophene(P3ht):[6,6]Phenyl C61 Butyric Methyl Acid Ester (PCBM) Blend Films
- 2011
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Ingår i: The Journal of Physical Chemistry Part B. - : American Chemical Society (ACS). - 1520-5207 .- 1520-6106. ; 115:51, s. 15174-15180
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Tidskriftsartikel (refereegranskat)abstract
- Charge generation and recombination are studied in blend films of poly-3-hexylthiophene (P3HT) and [6,6']phenyl C61 butyric acid methyl ester (PCBM) using ultrafast transient absorption spectroscopy. We find that the charge generation yield depends upon both blend film composition and thermal annealing. The data suggest that recombination occurs over a wide range of time scales and that, in the least favorable cases, the fastest charge recombination occurs on a time scale similar to exciton diffusion. The results are explained using a simple model that incorporates the effect of P3HT domain size on exciton diffusion and uses empirical models of recombination kinetics. We propose our method as a route to interpretation of spectroscopic data where different processes occur on similar time scales.
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| 36. |
- Klionsky, Daniel J., et al.
(författare)
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Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
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Ingår i: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
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Forskningsöversikt (refereegranskat)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
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| 37. |
- Krebs, Frederik C, et al.
(författare)
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A round robin study of flexible large-area roll-to-roll processed polymer solar cell modules
- 2009
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Ingår i: SOLAR ENERGY MATERIALS AND SOLAR CELLS. - : Elsevier BV. - 0927-0248. ; 93:11, s. 1968-1977
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Tidskriftsartikel (refereegranskat)abstract
- A round robin for the performance of roll-to-roll coated flexible large-area polymer solar-cell modules involving 18 different laboratories in Northern America, Europe and Middle East is presented. The study involved the performance measurement of the devices at one location (Riso DTU) followed by transportation to a participating laboratory for performance measurement and return to the starting location (Riso DTU) for re-measurement of the performance. It was found possible to package polymer solar-cell modules using a flexible plastic barrier material in such a manner that degradation of the devices played a relatively small role in the experiment that has taken place over 4 months. The method of transportation followed both air-mail and surface-mail paths.
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| 38. |
- Lundqvist, Jenny, 1975-, et al.
(författare)
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An in vivo study of the antimalarial effect of polyamine synthesis inhibitors in Plasmodium berghei
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Malaria is one of the most devastating diseases of the developing world responsible for approximately two million deaths annually. The high mortality together with the fact that resistance to available antimalarial drugs has increased, highlights the necessity of finding new chemotherapeutics against the parasite. Polyamines play a critical role in the regulation of cell proliferation and differentiation in most organisms including the malaria parasite. Therefore, targeting enzymes in the polyamine synthesis could be a possible approach to combat malaria. In order to evaluate the curative potential of the polyamine biosynthesis inhibitors S-adenosyl-3-thio-1,8-diaminooctane (AdoDATO) and trans-4-methylcyclohexylamine (4MCHA), which both target spermidine synthase, we took the advantage of an accessible mouse model using the rodent malaria parasite, P. berghei. Despite the promising inhibitory potential of AdoDATO, this drug was inefficient against malaria infection in mice. In contrast, 4MCHA restrained the parasite infection, which subsequently led to clearance within 24 days. This curative effect was not synergistically enhanced by combination treatment with the ornithine decarboxylase inhibitor, α-difluoromethylornithine (DFMO) and neither did a prophylactic treatment of 4MCHA increase the antimalarial effect. Interestingly, mice that received 4MCHA treatment gained a protective immunity towards malaria infection. The nature of this protective immunity is not established.
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| 39. |
- Lundqvist, Jenny, 1975-, et al.
(författare)
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Concomitant Infection Decreases the Malaria Burden but Escalates Relapsing Fever Borreliosis
- 2010
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Ingår i: Infection and Immunity. - : American Society for Microbiology. - 0019-9567 .- 1098-5522. ; 78:5, s. 1924-1930
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Tidskriftsartikel (refereegranskat)abstract
- About 500 million cases of malaria occur annually. However, a substantial number of patients who actually have relapsing fever (RF) Borrelia can be misdiagnosed with malaria due to similar manifestations and geographic distribution of the two diseases. More alarmingly, high prevalence of concomitant infections with malaria and RF Borrelia has been reported. Therefore, we used a mouse model to study the effects of such mixed infection. We observed a 21-fold increase in spirochete titers, whereas the numbers of parasitized erythrocytes were reduced 15-fold. This may be explained by polarization of the host immune response towards the intracellular malaria parasite, resulting in unaffected extracellular spirochetes and hosts that succumb to sepsis. Mixed infection also resulted in severe malaria anemia with low hemoglobin levels, even though the parasite counts were low. Overall, co-infected animals had higher fatality rate and shorter time to death than both malaria and RF single infection. Furthermore, secondary malaria infection reactivated a quiescent RF brain infection, which is the first evidence of a clinically and biologically relevant cue for reactivation of RF Borrelia infection. Our study highlights the importance of investigating concomitant infections in vivo to elucidate the immune responses that are involved in the clinical outcome.
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| 40. |
- Lundqvist, Jenny, 1975-, et al.
(författare)
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Mixed infection decreases malaria burden and escalate relapsing fever
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- About 500 million cases of malaria occur annually. However, a substantial number of patients who actually have relapsing fever (RF) Borrelia are misdiagnosed with malaria due to similar manifestation and geographic distribution of the two diseases. More alarmingly, high prevalence of mixed infections with malaria and RF Borrelia has been reported. Therefore, we developed a mouse model to study the effects of such mixed infection. We observed a 21-fold increase in spirochete titers, whereas parasitemia decreased 15-fold. This may be explained by polarization of the host immune response towards the intracellular malaria parasite, resulting in unaffected extracellular spirochetes and hosts succumb to sepsis. Furthermore, secondary malaria infection can reactivate a quiescent RF brain infection, which is the first evidence of a clinically and biologically relevant cue for reactivation of dormant RF Borrelia infection. Mixed infection also resulted in severe anemia even though the parasite counts were low. Our study highlights the importance of investigating mixed infections in vivo to elucidate the immune responses that are involved in the clinical outcome, and it also emphasizes the urgent need for improved diagnostics of malaria and other infectious diseases such as RF Borrelia.
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| 41. |
- MacLachlan, Andrew J, et al.
(författare)
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Polymer/Nanocrystal Hybrid Solar Cells : Influence of Molecular Precursor Design on Film Nanomorphology, Charge Generation and Device Performance.
- 2015
-
Ingår i: Advanced Functional Materials. - : Wiley. - 1616-301X .- 1616-3028. ; 25:3, s. 409-420
-
Tidskriftsartikel (refereegranskat)abstract
- In this work, molecular tuning of metal xanthate precursors is shown to have a marked effect on the heterojunction morphology of hybrid poly(3-hexylthiophene-2,5-diyl) (P3HT)/CdS blends and, as a result, the photochemical processes and overall performance of in situ fabricated hybrid solar cells. A series of cadmium xanthate complexes is synthesized for use as in situ precursors to cadmium sulfide nanoparticles in hybrid P3HT/CdS solar cells. The formation of CdS domains is studied by simultaneous GIWAXS (grazing incidence wide-angle X-ray scattering) and GISAXS (grazing incidence small-angle X-ray scattering), revealing knowledge about crystal growth and the formation of different morphologies observed using TEM (transmission electron microscopy). These measurements show that there is a strong relationship between precursor structure and heterojunction nanomorphology. A combination of TAS (transient absorption spectroscopy) and photovoltaic device performance measurements is used to show the intricate balance required between charge photogeneration and percolated domains in order to effectively extract charges to maximize device power conversion efficiencies. This study presents a strong case for xanthate complexes as a useful route to designing optimal heterojunction morphologies for use in the emerging field of hybrid organic/inorganic solar cells, due to the fact that the nanomorphology can be tuned via careful design of these precursor materials.
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| 42. |
- Melianas, Armantas
(författare)
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Non-Equilibrium Charge Motion in Organic Solar Cells
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Organic photovoltaic (OPV) devices based on semiconducting polymers and small molecules allow for a low cost alternative to inorganic solar cells. Recent developments show power conversion efficiencies as high as 10-12%, highlighting the potential of this technology. Nevertheless, further improvements are necessary to achieve commercialization.To a large extent the performance of these devices is dictated by their ability to extract the photo-generated charge, which is related to the charge carrier mobility. Various time-resolved and steady-state techniques are available to probe the charge carrier mobility in OPVs but often lead to different mobility values for one and the same system. Despite such conflicting observations it is generally assumed that charge transport in OPV devices can be described by well-defined charge carrier mobilities, typically obtained using a single steady-state technique. This thesis shows that the relevance of such well-defined mobilities for the charge separation and extraction processes is very limited.Although different transient techniques probe different time scales after photogeneration, they are mutually consistent as they probe the same physical mechanism governing charge motion – gradual thermalization of the photo-generated carriers in the disorder broadened density of states (DOS). The photo-generated carriers gradually lose their excess energy during transport to the extracting electrodes, but not immediately. Typically not all excess energy is dissipated as the photo-generated carriers tend to be extracted from the OPV device before reaching quasi-equilibrium.Carrier motion is governed by thermalization, leading to a time-dependent carrier mobility that is significantly higher than the steady-state mobility. This picture is confirmed by several transient techniques: Time-resolved Terahertz Spectroscopy (TRTS), Time-resolved Microwave Conductance (TRMC) combined with Transient Absorption (TA), electrical extraction of photo-induced charges (photo-CELIV). The connection between transient and steady-state mobility measurements (space-charge limited conductivity, SCLC) is described. Unification of transient opto-electric techniques to probe charge motion in OPVs is presented.Using transient experiments the distribution of extraction times of photo-generated charges in an operating OPV device has been determined and found to be strongly dispersive, spanning several decades in time. In view of the strong dispersion in extraction times the relevance of even a well-defined time-dependent mean mobility is limited.In OPVs a continuous ‘percolating’ donor network is often considered necessary for efficient hole extraction, whereas if the network is discontinuous, hole transport is thought to deteriorate significantly, limiting device performance. Here, it is shown that even highly diluted donor sites (5.7-10 %) in a buckminsterfullerene (C60) matrix enable reasonably efficient hole transport. Using transient measurements it is demonstrated that hole transport between isolated donor sites can occur by long-range hole tunneling (over distances of ~4 nm) through several C60 molecules – even a discontinuous donor network enables hole transport
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| 43. |
- Moia, Davide, et al.
(författare)
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The Role of Hole Transport between Dyes in Solid-State Dye-Sensitized Solar Cells
- 2015
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Ingår i: The Journal of Physical Chemistry C. - : AMER CHEMICAL SOC. - 1932-7447 .- 1932-7455. ; 119:33, s. 18975-18985
-
Tidskriftsartikel (refereegranskat)abstract
- In dye-sensitized solar cells (DSSCs) photo-generated positive charges are normally considered to be carried away from the dyes by a separate phase of hole-transporting material (HTM). We show that there can also be significant transport within the dye monolayer itself before the hole reaches the HTM. We quantify the fraction of dye regeneration in solid-state DSSCs that can be attributed to this process. By using cyclic voltammetry and transient anisotropy spectroscopy, we demonstrate that the rate of interdye hole transport is prevented both on micrometer and nanometer length scales by reducing the dye loading on the TiO2 surface. The dye regeneration yield is quantified for films with high and low dye loadings (with and without hole percolation in the dye monolayer) infiltrated with varying levels of HTM. Interdye hole transport can account for >50% of the overall dye regeneration with low HTM pore filling. This is reduced to about 5% when the infiltration of the HTM in the pores is optimized in 2 mu m thick films. Finally, we use hole transport in the dye monolayer to characterize the spatial distribution of the HTM phase in the pores of the dyed mesoporous TiO2.
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| 44. |
- Nelson, Marie, 1970-, et al.
(författare)
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Att dela språk men inte samtalsmönster : Återkoppling i sverigesvenska och finlandssvenska handledningssamtal
- 2015
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Ingår i: Folkmålsstudier. - 0356-1771. ; 53, s. 141-166
-
Tidskriftsartikel (refereegranskat)abstract
- Sharing language but not communicative patterns: Feedback in Sweden-Swedish and Finland-Swedish academic counselling interactionIn this article, we present a study of oral feedback (back-channels and responsive turns) given in academic counselling meetings between an essay supervisor and one or two students. The purpose of these meetings is to discuss and improve an academic text written by the students. Our data consist of naturally occurring Sweden-Swedish and Finland-Swedish institutional interactions at the university level. The overall aim of the study is to compare feedback patterns in the Sweden-Swedish and the Finland- Swedish data and to contribute to the field of variational pragmatics. A detailed analysis of the recorded interactions reveals overt differences in the frequency, intensity and distribution of feedback in the two varieties of Swedish. In the Sweden-Swedish data, there is a preference for relational work, evidenced, for instance, by students praising the advice given by the supervisor. In the Finland-Swedish data, an orientation towards clarity is prominent and corrective advice, for instance, is usually uttered in a straightforward way. Our results support previous findings on communicative patterns in Sweden and Finland. These findings highlight the dialogic nature of institutional communication in Sweden, on the one hand, and the orientation to the task and its result in comparable situations in Finland, on the other. The outcome of this study adds to the understanding of the communicative patterns of Sweden- Swedish and Finland-Swedish with a detailed analysis of the oral feedback occurring in counselling meetings.
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| 45. |
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| 46. |
- Sandholm, Niina, et al.
(författare)
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New susceptibility loci associated with kidney disease in type 1 diabetes
- 2012
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Ingår i: PLOS Genetics. - San Francisco, USA : Public Library of Science, PLOS. - 1553-7390 .- 1553-7404. ; 8:9, s. e1002921-
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Tidskriftsartikel (refereegranskat)abstract
- Diabetic kidney disease, or diabetic nephropathy (DN), is a major complication of diabetes and the leading cause of end-stage renal disease (ESRD) that requires dialysis treatment or kidney transplantation. In addition to the decrease in the quality of life, DN accounts for a large proportion of the excess mortality associated with type 1 diabetes (T1D). Whereas the degree of glycemia plays a pivotal role in DN, a subset of individuals with poorly controlled T1D do not develop DN. Furthermore, strong familial aggregation supports genetic susceptibility to DN. However, the genes and the molecular mechanisms behind the disease remain poorly understood, and current therapeutic strategies rarely result in reversal of DN. In the GEnetics of Nephropathy: an International Effort (GENIE) consortium, we have undertaken a meta-analysis of genomewide association studies (GWAS) of T1D DN comprising similar to 2.4 million single nucleotide polymorphisms (SNPs) imputed in 6,691 individuals. After additional genotyping of 41 top ranked SNPs representing 24 independent signals in 5,873 individuals, combined meta-analysis revealed association of two SNPs with ESRD: rs7583877 in the AFF3 gene (P = 1.2 x 10(-8)) and an intergenic SNP on chromosome 15q26 between the genes RGMA and MCTP2, rs12437854 (P = 2.0 x 10(-9)). Functional data suggest that AFF3 influences renal tubule fibrosis via the transforming growth factor-beta (TGF-beta 1) pathway. The strongest association with DN as a primary phenotype was seen for an intronic SNP in the ERBB4 gene (rs7588550, P = 2.1 x 10(-7)), a gene with type 2 diabetes DN differential expression and in the same intron as a variant with cis-eQTL expression of ERBB4. All these detected associations represent new signals in the pathogenesis of DN.
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| 47. |
- Styrkarsdottir, Unnur, et al.
(författare)
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GWAS of bone size yields twelve loci that also affect height, BMD, osteoarthritis or fractures
- 2019
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1
-
Tidskriftsartikel (refereegranskat)abstract
- Bone area is one measure of bone size that is easily derived from dual-energy X-ray absorptiometry (DXA) scans. In a GWA study of DXA bone area of the hip and lumbar spine (N ≥ 28,954), we find thirteen independent association signals at twelve loci that replicate in samples of European and East Asian descent (N = 13,608 – 21,277). Eight DXA area loci associate with osteoarthritis, including rs143384 in GDF5 and a missense variant in COL11A1 (rs3753841). The strongest DXA area association is with rs11614913[T] in the microRNA MIR196A2 gene that associates with lumbar spine area (P = 2.3 × 10 −42 , β = −0.090) and confers risk of hip fracture (P = 1.0 × 10 −8 , OR = 1.11). We demonstrate that the risk allele is less efficient in repressing miR-196a-5p target genes. We also show that the DXA area measure contributes to the risk of hip fracture independent of bone density.
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| 48. |
- Yan, Jun, et al.
(författare)
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Identifying structure-absorption relationships and predicting absorption strength of non-fullerene acceptors for organic photovoltaics
- 2022
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Ingår i: Energy & Environmental Science. - : ROYAL SOC CHEMISTRY. - 1754-5692 .- 1754-5706. ; 15:7, s. 2958-2973
-
Tidskriftsartikel (refereegranskat)abstract
- Non-fullerene acceptors (NFAs) are excellent light harvesters, yet the origin of their high optical extinction is not well understood. In this work, we investigate the absorption strength of NFAs by building a database of time-dependent density functional theory (TDDFT) calculations of similar to 500 pi-conjugated molecules. The calculations are first validated by comparison with experimental measurements in solution and solid state using common fullerene and non-fullerene acceptors. We find that the molar extinction coefficient (epsilon(d,max)) shows reasonable agreement between calculation in vacuum and experiment for molecules in solution, highlighting the effectiveness of TDDFT for predicting optical properties of organic pi-conjugated molecules. We then perform a statistical analysis based on molecular descriptors to identify which features are important in defining the absorption strength. This allows us to identify structural features that are correlated with high absorption strength in NFAs and could be used to guide molecular design: highly absorbing NFAs should possess a planar, linear, and fully conjugated molecular backbone with highly polarisable heteroatoms. We then exploit a random decision forest algorithm to draw predictions for epsilon(d,max) using a computational framework based on extended tight-binding Hamiltonians, which shows reasonable predicting accuracy with lower computational cost than TDDFT. This work provides a general understanding of the relationship between molecular structure and absorption strength in pi-conjugated organic molecules, including NFAs, while introducing predictive machine-learning models of low computational cost.
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| 49. |
- Zhang, Huotian
(författare)
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Loss Mechanisms In Non-Fullerene Organic Solar Cells
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Photovoltaics are one of the most important sustainable energy sources in the 21st century. Among photovoltaics, organic solar cells (OSCs) offer many advantages such as ease of processing, lightweight, the potential for flexibility, and tunable properties. Its peculiar nature and complexity present a fascinating charm, attracting many researchers. Thanks to researchers' efforts, the power conversion efficiency (PCE) of OSCs has been boosted from 1% to 19% during the last three decades. Despite the exciting PCE, some problems remain to be solved, for example, the large voltage loss and long-term stability. The aim of this thesis is to understand the fundamental physics of the state-of-the-art OSCs, especially the loss mechanism. Ultimately, properly understanding the mechanisms will sever as the basis of OSCs further improvements and commercialization. This work focuses on the loss mechanisms of OSCs, particularly the open-circuit voltage and the fill factor. The beginning of this thesis introduces basic concepts regarding semiconductors physics and donor-acceptor OSCs. This part explains how a photon is used to generate electricity and the fundamentals of organic electronics. Subsequently, the detailed balance in a solar cell is reviewed, which is the basis of voltage loss analysis. In this part, we see how the input, recombination, and output form a balance. Then, the way to determine the voltage loss is shown, and the latest understandings in reducing the loss are reviewed. The fill factor, as a measure of the quality of a solar cell, is a complex parameter, especially in OSCs.The latter part of this thesis starts from the photophysical processes in an OSC, and then relates intrinsic parameters to the fill factor. The figure of merits has been employed to express the fill factor analytically. In the end, experimental methods and basic principles for the previous analysis are introduced, including Fourier transform infrared spectroscopy, the external quantum efficiency of photovoltaics (EQEPV), spectrograph for electroluminescence or photoluminescence, transient absorption, and time-delayed collection field. Overall, the thesis combined thermal dynamics and charge dynamics to analyze voltage losses and fill factor losses. The author hopes this work can contribute to a better understanding of the loss mechanisms OSCs.
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| 50. |
- Zhang, Silan, 1992-
(författare)
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Organic Electrochemical Transistors : Materials and Challenges
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The use of organic mixed ionic-electronic conductors (OMIECs) has demonstrated the potential to transform the field of bioelectronics, spanning from medical diagnostics to neuromorphic computing hardware. To keep up with the fast-paced demands, it is crucial to develop customizable device fabrication, design new materials, improve operation stability, and explore the ion-electron interactions within OMIECs. This thesis explores the application of OMIECs in organic electrochemical transistors (OECTs), a crucial component of a range of organic bioelectronic devices. To meet applications requiring rapid design iterations and leveraging digitally enabled direct-write techniques, we developed a novel approach for fabricating fully 3D-printed OECTs using a direct-write additive process. This method involves utilizing 3D printable inks with conductive, semiconductive, insulating, and electrolyte properties. The resulting fully 3D-printed OECTs operate in the depletion mode and can be produced on flexible substrates, ensuring excellent mechanical durability and resilience in various environmental conditions. These 3D-printed OECTs exhibit impressive dopamine biosensing capabilities, detecting concentrations as low as 6 µM without the need for metal gate electrodes. Furthermore, they demonstrate long-term memory response lasting up to approximately 1 hour, highlighting their potential for diverse applications such as sensors and neuromorphic hardware. We have addressed the issue of sluggish response times in printed OECTs by utilizing multi-walled carbon nanotubes (MWCNTs) and the π-conjugated redox polymer called poly(benzimidazobenzo-phenanthroline) (BBL) to create high-performing n-type OECTs. By incorporating MWCNTs, we were able to improve the electron mobility of the transistors by more than 10 times, resulting in a rapid response time of just 15 ms and a high μC* value (which is the product of electron mobility and volumetric capacitance) of approximately 1 F cm–1 V−1 s−1. These breakthroughs have allowed us to develop complementary inverters that have a voltage gain of over 16, a significant worst-case noise margin at a supply voltage lower than 0.6 V and consume less than 1 µW of power. However, the operational stability of complementary inverters is hindered by the degradation of p-type OMIECs. The oxygen reduction reaction (ORR) is a common electrochemical side reaction that poses challenges to the stability of OECTs, but the underlying connection between ORR and material degradation remains poorly understood. In our investigation, we examined the influence of ORR on the stability and degradation mechanisms of thiophene-based OECTs. Our findings reveal that the polymer backbone experiences degradation as a result of the pH increase during ORR. To address this issue, we introduced a protective polymer glue layer between the semiconductor channel and the aqueous electrolyte, effectively suppressing the occurrence of ORR and significantly enhancing the stability of the OECTs. This improvement is evident in the nearly 90% retention of current during ≈2 hours of cycling in the saturation regime. Finally, we investigated the ionic-electronic transport properties in BBL-based OECTs using various electrolytes. We found that the peak drain current is achieved at a doping level of 1 electron per repeating unit, decreasing thereafter. The interaction between ions and the polymer reduces the voltage needed for this level of doping but also lowers the peak drain current. Unlike thiophene-based OECTs, larger cation sizes don't improve BBL-based OECT performance. Additionally, Lewis acids adversely affect BBL's electrical properties due to their impact on the polymer microstructure. We hope these studies will inspire our peers in the field of materials synthesis, device processing, and scalable digital techniques, paving the way for next-generation, reliable, and safe bioelectronics.
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