| 1. |
- Niemi, MEK, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 2. |
- Abel, I, et al.
(författare)
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Overview of the JET results with the ITER-like wall
- 2013
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Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 53:10, s. 104002-
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Tidskriftsartikel (refereegranskat)abstract
- Following the completion in May 2011 of the shutdown for the installation of the beryllium wall and the tungsten divertor, the first set of JET campaigns have addressed the investigation of the retention properties and the development of operational scenarios with the new plasma-facing materials. The large reduction in the carbon content (more than a factor ten) led to a much lower Z(eff) (1.2-1.4) during L- and H-mode plasmas, and radiation during the burn-through phase of the plasma initiation with the consequence that breakdown failures are almost absent. Gas balance experiments have shown that the fuel retention rate with the new wall is substantially reduced with respect to the C wall. The re-establishment of the baseline H-mode and hybrid scenarios compatible with the new wall has required an optimization of the control of metallic impurity sources and heat loads. Stable type-I ELMy H-mode regimes with H-98,H-y2 close to 1 and beta(N) similar to 1.6 have been achieved using gas injection. ELM frequency is a key factor for the control of the metallic impurity accumulation. Pedestal temperatures tend to be lower with the new wall, leading to reduced confinement, but nitrogen seeding restores high pedestal temperatures and confinement. Compared with the carbon wall, major disruptions with the new wall show a lower radiated power and a slower current quench. The higher heat loads on Be wall plasma-facing components due to lower radiation made the routine use of massive gas injection for disruption mitigation essential.
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| 3. |
- Romanelli, F, et al.
(författare)
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Overview of the JET results
- 2011
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Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 51:9
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Tidskriftsartikel (refereegranskat)abstract
- Since the last IAEA Conference JET has been in operation for one year with a programmatic focus on the qualification of ITER operating scenarios, the consolidation of ITER design choices and preparation for plasma operation with the ITER-like wall presently being installed in JET. Good progress has been achieved, including stationary ELMy H-mode operation at 4.5 MA. The high confinement hybrid scenario has been extended to high triangularity, lower ρ*and to pulse lengths comparable to the resistive time. The steady-state scenario has also been extended to lower ρ*and ν*and optimized to simultaneously achieve, under stationary conditions, ITER-like values of all other relevant normalized parameters. A dedicated helium campaign has allowed key aspects of plasma control and H-mode operation for the ITER non-activated phase to be evaluated. Effective sawtooth control by fast ions has been demonstrated with3He minority ICRH, a scenario with negligible minority current drive. Edge localized mode (ELM) control studies using external n = 1 and n = 2 perturbation fields have found a resonance effect in ELM frequency for specific q95values. Complete ELM suppression has, however, not been observed, even with an edge Chirikov parameter larger than 1. Pellet ELM pacing has been demonstrated and the minimum pellet size needed to trigger an ELM has been estimated. For both natural and mitigated ELMs a broadening of the divertor ELM-wetted area with increasing ELM size has been found. In disruption studies with massive gas injection up to 50% of the thermal energy could be radiated before, and 20% during, the thermal quench. Halo currents could be reduced by 60% and, using argon/deuterium and neon/deuterium gas mixtures, runaway electron generation could be avoided. Most objectives of the ITER-like ICRH antenna have been demonstrated; matching with closely packed straps, ELM resilience, scattering matrix arc detection and operation at high power density (6.2 MW m-2) and antenna strap voltages (42 kV). Coupling measurements are in very good agreement with TOPICA modelling. © 2011 IAEA, Vienna.
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| 4. |
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| 5. |
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| 6. |
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| 7. |
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| 8. |
- Tartaglia, L., et al.
(författare)
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The Early Detection and Follow-up of the Highly Obscured Type II Supernova 2016ija/DLT16am
- 2018
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 853:1
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Tidskriftsartikel (refereegranskat)abstract
- We present our analysis of the Type II supernova DLT16am (SN 2016ija). The object was discovered during the ongoing D < 40 Mpc (DLT40) one-day cadence supernova search at r similar to 20.1 mag in the edge-on nearby (D = 20.0 +/- 4.0 Mpc) galaxy NGC 1532. The subsequent prompt and high-cadenced spectroscopic and photometric follow-up revealed a highly extinguished transient, with E(B - V) = 1.95 +/- 0.15 mag, consistent with a standard extinction law with R-V = 3.1 and a bright (M-V = -18.48 +/- 0.77 mag) absolute peak magnitude. A comparison of the photometric features with those of large samples of SNe II reveals a fast rise for the derived luminosity and a relatively short plateau phase, with a slope of S-50V = 0.84 +/- 0.04 mag/50 days, consistent with the photometric properties typical of those of fast-declining SNe II. Despite the large uncertainties on the distance and the extinction in the direction of DLT16am, the measured photospheric expansion velocity and the derived absolute V-band magnitude at similar to 50 days after the explosion match the existing luminosity-velocity relation for SNe II.
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| 9. |
- Azarbarzin, A., et al.
(författare)
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Cardiovascular Benefit of Continuous Positive Airway Pressure in Adults with Coronary Artery Disease and Obstructive Sleep Apnea without Excessive Sleepiness
- 2022
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Ingår i: American Journal of Respiratory and Critical Care Medicine. - 1073-449X .- 1535-4970. ; 206:6, s. 767-774
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Tidskriftsartikel (refereegranskat)abstract
- Rationale: Randomized controlled trials of continuous positive airway pressure (CPAP) in patients with obstructive sleep apnea (OSA) have not demonstrated protection against adverse cardiovascular outcomes. Recently, observational studies revealed that OSA-related cardiovascular risk is concentrated in patients with an elevated pulse rate response to respiratory events (Delta HR). Objectives: Here, in this post hoc analysis of a prospective clinical trial, we test the hypothesis that a greater pretreatment Delta HR is associated with greater CPAP-related protection against adverse cardiovascular outcomes. Methods: Delta HR was measured from baseline polysomnography of the RICCADSA (Randomized Intervention with CPAP in CAD and OSA) randomized controlled trial (patients with coronary artery disease [CAD] and OSA [apnea-hypopnea index >= 15 events/h] with Epworth Sleepiness Scale score, 10; n(CPAP):n(control) = 113:113; male, 85%; age, 66 +/- 8 [mean +/- SD] yr). The primary outcome was a composite of repeat revascularization, myocardial infarction, stroke, and cardiovascular mortality. Multivariable Cox regression assessed whether the effect of CPAP was moderated by Delta HR (treatmentby-Delta HR interaction). Measurements and Main Results: The CPAP-related reduction in risk increased progressively with increasing pretreatment Delta HR (interaction hazard ratio [95% confidence interval], 0.49 [0.27 to 0.90] per SD increase in Delta HR; P, 0.05). This means that in patients with a Delta HR of 1 SD above the mean (i.e., 10 beats/min), CPAP was estimated to reduce cardiovascular risk by 59% (6% to 82%) (P<0.05), but no significant risk reduction was estimated in patients with a mean Delta HR (6 beats/min; CPAP risk reduction, 16% [253% to 54%]; P= 0.6). Conclusions: The protective effect of CPAP in patients with CAD and OSA without excessive sleepiness was modified by the Delta HR. Specifically, patients with higher Delta HR exhibit greater cardiovascular benefit from CPAP therapy.
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| 10. |
- Zhang, L, et al.
(författare)
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An MPER antibody neutralizes HIV-1 using germline features shared among donors
- 2019
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Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1, s. 5389-
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Tidskriftsartikel (refereegranskat)abstract
- The membrane-proximal external region (MPER) of HIV-1 envelope glycoprotein (Env) can be targeted by neutralizing antibodies of exceptional breadth. MPER antibodies usually have long, hydrophobic CDRH3s, lack activity as inferred germline precursors, are often from the minor IgG3 subclass, and some are polyreactive, such as 4E10. Here we describe an MPER broadly neutralizing antibody from the major IgG1 subclass, PGZL1, which shares germline V/D-region genes with 4E10, has a shorter CDRH3, and is less polyreactive. A recombinant sublineage variant pan-neutralizes a 130-isolate panel at 1.4 μg/ml (IC50). Notably, a germline revertant with mature CDR3s neutralizes 12% of viruses and still binds MPER after DJ reversion. Crystal structures of lipid-bound PGZL1 variants and cryo-EM reconstruction of an Env-PGZL1 complex reveal how these antibodies recognize MPER and viral membrane. Discovery of common genetic and structural elements among MPER antibodies from different patients suggests that such antibodies could be elicited using carefully designed immunogens.
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| 11. |
- Alexander, Peter, et al.
(författare)
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Assessing uncertainties in land cover projections
- 2017
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013. ; 23:2, s. 767-781
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Tidskriftsartikel (refereegranskat)abstract
- Understanding uncertainties in land cover projections is critical to investigating land-based climate mitigation policies, assessing the potential of climate adaptation strategies and quantifying the impacts of land cover change on the climate system. Here, we identify and quantify uncertainties in global and European land cover projections over a diverse range of model types and scenarios, extending the analysis beyond the agro-economic models included in previous comparisons. The results from 75 simulations over 18 models are analysed and show a large range in land cover area projections, with the highest variability occurring in future cropland areas. We demonstrate systematic differences in land cover areas associated with the characteristics of the modelling approach, which is at least as great as the differences attributed to the scenario variations. The results lead us to conclude that a higher degree of uncertainty exists in land use projections than currently included in climate or earth system projections. To account for land use uncertainty, it is recommended to use a diverse set of models and approaches when assessing the potential impacts of land cover change on future climate. Additionally, further work is needed to better understand the assumptions driving land use model results and reveal the causes of uncertainty in more depth, to help reduce model uncertainty and improve the projections of land cover.
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| 12. |
- Zinchuk, A. V., et al.
(författare)
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Physiological Traits and Adherence to Sleep Apnea Therapy in Individuals with Coronary Artery Disease
- 2021
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Ingår i: American Journal of Respiratory and Critical Care Medicine. - 1073-449X. ; 204:6, s. 703-712
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Tidskriftsartikel (refereegranskat)abstract
- Rationale: Untreated obstructive sleep apnea (OSA) is associated with adverse outcomes in patients with coronary artery disease (CAD). Continuous positive airway pressure (CPAP) is the most common treatment, but despite interventions addressing established adherence determinants, CPAP use remains poor. Objectives: To determine whether physiological traits that cause OSA are associated with long-termCPAP adherence in patients with CAD. Methods: Participants in the RICCADSA (Randomized Intervention with CPAP in CAD and OSA) trial with objective CPAP adherence (h/night) over 2 years and analyzable raw polysomnography data were included (N= 249). The physiological traits-loop gain, arousal threshold (ArTH), pharyngeal collapsibility (<(V)over dot> passive), and pharyngeal muscle compensation (<(V)over dot>comp)-were measured by using polysomnography. Linear mixed models were used to assess the relationship between the traits and adherence. We also compared actual CPAP adherence between those with physiologically predicted "poor" adherence (lowest quartile of predicted adherence) and those with physiologically predicted "good" adherence (all others). Measurements and Main Results: The median (interquartile range) CPAP use declined from 3.2 (1.0-5.8) h/night to 3.0 (0.0-5.6) h/night over 24 months (P, 0.001). In analyses adjusted for demographics, anthropometrics, OSA characteristics, and clinical comorbidities, a lower ArTH was associated with worse CPAP adherence (0.7 h/SD of the ArTH; P = 0.021). Both high and low <(V)over dot> comp were associated with lower adherence (P = 0.008). Those with predicted poor adherence exhibited markedly lower CPAP use than those with predicted good adherence for up to 2 years of follow-up (group differences of 2.0-3.2 h/night; P, 0.003 for all). Conclusions: A low ArTH, as well as a very low and high <(V)over dot> comp, are associated with worse long-term CPAP adherence in patients with CAD and OSA. Physiological traits-alongside established determinants-may help predict and improve CPAP adherence.
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| 13. |
- Brommage, Robert, et al.
(författare)
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NOTUM inhibition increases endocortical bone formation and bone strength
- 2019
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Ingår i: Bone Research. - : Springer Science and Business Media LLC. - 2095-4700 .- 2095-6231. ; 7:2
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Tidskriftsartikel (refereegranskat)abstract
- The disability, mortality and costs caused by non-vertebral osteoporotic fractures are enormous. Existing osteoporosis therapies are highly effective at reducing vertebral but not non-vertebral fractures. Cortical bone is a major determinant of non-vertebral bone strength. To identify novel osteoporosis drug targets, we phenotyped cortical bone of 3 366 viable mouse strains with global knockouts of druggable genes. Cortical bone thickness was substantially elevated in Notum(-/-) mice. NOTUM is a secreted WNT lipase and we observed high NOTUM expression in cortical bone and osteoblasts but not osteoclasts. Three orally active small molecules and a neutralizing antibody inhibiting NOTUM lipase activity were developed. They increased cortical bone thickness and strength at multiple skeletal sites in both gonadal intact and ovariectomized rodents by stimulating endocortical bone formation. Thus, inhibition of NOTUM activity is a potential novel anabolic therapy for strengthening cortical bone and preventing non-vertebral fractures.
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| 14. |
- Prestele, Reinhard, et al.
(författare)
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Hotspots of uncertainty in land-use and land-cover change projections : a global-scale model comparison
- 2016
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 22:12, s. 3967-3983
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Tidskriftsartikel (refereegranskat)abstract
- Model-based global projections of future land-use and land-cover (LULC) change are frequently used in environmental assessments to study the impact of LULC change on environmental services and to provide decision support for policy. These projections are characterized by a high uncertainty in terms of quantity and allocation of projected changes, which can severely impact the results of environmental assessments. In this study, we identify hotspots of uncertainty, based on 43 simulations from 11 global-scale LULC change models representing a wide range of assumptions of future biophysical and socioeconomic conditions. We attribute components of uncertainty to input data, model structure, scenario storyline and a residual term, based on a regression analysis and analysis of variance. From this diverse set of models and scenarios, we find that the uncertainty varies, depending on the region and the LULC type under consideration. Hotspots of uncertainty appear mainly at the edges of globally important biomes (e.g., boreal and tropical forests). Our results indicate that an important source of uncertainty in forest and pasture areas originates from different input data applied in the models. Cropland, in contrast, is more consistent among the starting conditions, while variation in the projections gradually increases over time due to diverse scenario assumptions and different modeling approaches. Comparisons at the grid cell level indicate that disagreement is mainly related to LULC type definitions and the individual model allocation schemes. We conclude that improving the quality and consistency of observational data utilized in the modeling process and improving the allocation mechanisms of LULC change models remain important challenges. Current LULC representation in environmental assessments might miss the uncertainty arising from the diversity of LULC change modeling approaches, and many studies ignore the uncertainty in LULC projections in assessments of LULC change impacts on climate, water resources or biodiversity.
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| 15. |
- Strassberger, C., et al.
(författare)
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Night-to-Night Variability of Polysomnography-Derived Physiologic Endotypic Traits in Patients With Moderate to Severe OSA
- 2023
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Ingår i: Chest. - : Elsevier BV. - 0012-3692. ; 163:5, s. 1266-1278
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Emerging data suggest that determination of physiologic endotypic traits (eg, loop gain) may enable precision medicine in OSA.RESEARCH QUESTION: Does a single-night assessment of polysomnography-derived endotypic traits provide reliable estimates in moderate to severe OSA?STUDY DESIGN AND METHODS: Two consecutive in-lab polysomnography tests from a clinical trial (n = 67; male, 69%; mean +/- SD age, 61 +/- 10 years; apnea-hypopnea index [AHI] 53 +/- 22 events/h) were used for the reliability analysis. Endotypic traits, reflecting upper airway collapsibility (ventilation at eupneic drive [Vpassive]), upper airway dilator muscle tone (ventilation at the arousal threshold [Vactive]), loop gain (stability of ventilatory control, LG1), and arousal threshold (ArTh) were determined. Reliability was expressed as an intraclass correlation coefficient (ICC). Minimal detectable differences (MDDs) were computed to pro-vide an estimate of maximum spontaneous variability. Further assessment across four repeated polysomnography tests was performed in a subcohort (n = 22). RESULTS: Reliability of endotypic traits between the two consecutive nights was moderate to good (ICC: Vpassive = 0.82, Vactive = 0.76, LG1 = 0.72, ArTh = 0.83). Variability in AHI, but not in body position or in sleep stages, was associated with fluctuations in Vpassive and Vactive (r = -0.49 and r = -0.41, respectively; P < .001 for both). MDDs for single-night assessments were: Vpassive = 22, Vactive = 34, LG1 = 0.17, and ArTh = 21. Multiple assessments (mean of two nights, n = 22) further reduced MDDs by approximately 20% to 30%. INTERPRETATION: Endotypic trait analysis using a single standard polysomnography shows acceptable reliability and reproducibility in patients with moderate to severe OSA. The re-ported MDDs of endotypic traits may facilitate the quantification of relevant changes and may guide future evaluation of interventions in OSA. CHEST 2023; 163(5):1266-1278
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| 16. |
- Blaise, Benjamin J., et al.
(författare)
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Statistical analysis in metabolic phenotyping
- 2021
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Ingår i: Nature Protocols. - : Nature Publishing Group. - 1754-2189 .- 1750-2799. ; 16:9, s. 4299-4326
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Forskningsöversikt (refereegranskat)abstract
- Metabolic phenotyping is an important tool in translational biomedical research. The advanced analytical technologies commonly used for phenotyping, including mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy, generate complex data requiring tailored statistical analysis methods. Detailed protocols have been published for data acquisition by liquid NMR, solid-state NMR, ultra-performance liquid chromatography (LC-)MS and gas chromatography (GC-)MS on biofluids or tissues and their preprocessing. Here we propose an efficient protocol (guidelines and software) for statistical analysis of metabolic data generated by these methods. Code for all steps is provided, and no prior coding skill is necessary. We offer efficient solutions for the different steps required within the complete phenotyping data analytics workflow: scaling, normalization, outlier detection, multivariate analysis to explore and model study-related effects, selection of candidate biomarkers, validation, multiple testing correction and performance evaluation of statistical models. We also provide a statistical power calculation algorithm and safeguards to ensure robust and meaningful experimental designs that deliver reliable results. We exemplify the protocol with a two-group classification study and data from an epidemiological cohort; however, the protocol can be easily modified to cover a wider range of experimental designs or incorporate different modeling approaches. This protocol describes a minimal set of analyses needed to rigorously investigate typical datasets encountered in metabolic phenotyping.
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| 17. |
- Caron, Bénédicte, et al.
(författare)
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IOIBD Recommendations for Clinical Trials in Ulcerative Proctitis : the PROCTRIAL Consensus
- 2022
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Ingår i: Clinical Gastroenterology and Hepatology. - : Elsevier. - 1542-3565 .- 1542-7714. ; 20:11, s. 2169-2627.e1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND AIMS: Clinical trials evaluating biologics and small molecules in patients with ulcerative colitis are predominantly excluding ulcerative proctitis. The objective of the PROCTRIAL (Definition and endpoints for ulcerative PROCtitis in clinical TRIALs) initiative was to develop consensus statements for definitions, inclusion criteria, and endpoints for the evaluation of ulcerative proctitis in adults.METHODS: Thirty-five international experts held a consensus meeting to define ulcerative proctitis, and the endpoints to use in clinical trials. Based on a systematic review of the literature, statements were generated, discussed, and approved by the working group participants using a modified Delphi method. Consensus was defined as at least 75% agreement among voters.RESULTS: The group agreed that the diagnosis of ulcerative proctitis should be made by ileocolonoscopy and confirmed by histopathology, with the exclusion of infections, drug-induced causes, radiation, trauma, and Crohn's disease. Ulcerative proctitis was defined as macroscopic extent of lesions limited to 15 cm distance from the anal verge in adults. Primary and secondary endpoints were identified to capture response of ulcerative proctitis to therapy. A combined clinical and endoscopic primary endpoint for the evaluation of ulcerative proctitis disease activity is proposed. Secondary endpoints which should be evaluated include endoscopic remission, histological remission, mucosal healing, histologic endoscopic mucosal improvement, disability, fecal incontinence, urgency, constipation, and health-related quality of life.CONCLUSION: In response to the need for guidance on the design of clinical trials in patients with ulcerative proctitis, the PROCTRIAL consensus provides recommendations on the definition and endpoints for ulcerative proctitis clinical trials.
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| 18. |
- Ellison, David, et al.
(författare)
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Trees, forests and water : Cool insights for a hot world
- 2017
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Ingår i: Global Environmental Change. - : Elsevier BV. - 0959-3780 .- 1872-9495. ; 43, s. 51-61
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Tidskriftsartikel (refereegranskat)abstract
- Forest-driven water and energy cycles are poorly integrated into regional, national, continental and global decision-making on climate change adaptation, mitigation, land use and water management. This constrains humanity's ability to protect our planet's climate and life-sustaining functions. The substantial body of research we review reveals that forest, water and energy interactions provide the foundations for carbon storage, for cooling terrestrial surfaces and for distributing water resources. Forests and trees must be recognized as prime regulators within the water, energy and carbon cycles. If these functions are ignored, planners will be unable to assess, adapt to or mitigate the impacts of changing land cover and climate. Our call to action targets a reversal of paradigms, from a carbon-centric model to one that treats the hydrologic and climate-cooling effects of trees and forests as the first order of priority. For reasons of sustainability, carbon storage must remain a secondary, though valuable, by-product. The effects of tree cover on climate at local, regional and continental scales offer benefits that demand wider recognition. The forest- and tree-centered research insights we review and analyze provide a knowledge-base for improving plans, policies and actions. Our understanding of how trees and forests influence water, energy and carbon cycles has important implications, both for the structure of planning, management and governance institutions, as well as for how trees and forests might be used to improve sustainability, adaptation and mitigation efforts.
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| 19. |
- Ho, Kok Sun, et al.
(författare)
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Ileal pouch anal anastomosis for ulcerative colitis is feasible for septuagenarians.
- 2006
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Ingår i: Colorectal disease : the official journal of the Association of Coloproctology of Great Britain and Ireland. - : Wiley. - 1462-8910. ; 8:3, s. 235-8
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Proctocolectomy and ileal pouch anal anastomosis (IPAA) has become the standard surgery for patients with mucosal ulcerative colitis (MUC). Although there is no absolute age limitation, there are concerns as to its use in elderly patients due to the risks of potential complications and poor function. The aim of this study was to assess the complications and outcome of patients over the age of 70 years with MUC who underwent IPAA. Results in these patients were compared to the results in a group of patients aged less than 70 years who had IPAA. METHODS: After Institutional Review Board approval, a retrospective review of the medical records of patients with MUC who underwent IPAA was undertaken. These patients were divided into four age groups: <30 years of age, 30-49 years, 50-69 years, >or=70 years. RESULTS: From 1989 to 2001, 330 patients underwent IPAA for preoperative clinical and histopathological and postoperative histopathologically confirmed MUC; 17 were aged>or=70 years. The mean hospital stay was 5.8 (SEM 0.7) days in the patients aged<70 years and 6.0 (SEM 0.4) days in the patients aged>or=70 years (P=0.911). Postoperative complications occurred in 39% of patients>or=70 years and in 40% in the <70 years group (P=0.08). Pouch failure occurred in two (11.8%) patients>or=70 years and in 6 (1.9%)<70 (P=0.2). CONCLUSION: IPAA is a safe and feasible option in MUC patients over the age of 70 with functional results similar to results seen in younger patients.
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| 20. |
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| 22. |
- Mantel, A., et al.
(författare)
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Assumptions and guarantees for compositional noninterference
- 2011
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Ingår i: Proceedings - IEEE Computer Security Foundations Symposium. - 1940-1434. - 9780769543659 ; , s. 218-232
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Konferensbidrag (refereegranskat)abstract
- The idea of building secure systems by plugging together "secure" components is appealing, but this requires a definition of security which, in addition to taking care of top-level security goals, is strengthened appropriately in order to be compositional. This approach has been previously studied for information-flow security of shared-variable concurrent programs, but the price for compositionality is very high: a thread must be extremely pessimistic about what an environment might do with shared resources. This pessimism leads to many intuitively secure threads being labelled as insecure. Since in practice it is only meaningful to compose threads which follow an agreed protocol for data access, we take advantage of this to develop a more liberal compositional security condition. The idea is to give the security definition access to the intended pattern of data usage, as expressed by assumption-guarantee style conditions associated with each thread. We illustrate the improved precision by developing the first flow-sensitive security type system that provably enforces a noninterference-like property for concurrent programs. © 2011 IEEE.
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| 23. |
- Palmer, Elizabeth E., et al.
(författare)
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Functional and clinical studies reveal pathophysiological complexity of CLCN4-related neurodevelopmental condition
- 2023
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Ingår i: Molecular Psychiatry. - : SPRINGERNATURE. - 1359-4184 .- 1476-5578. ; 28:2, s. 668-697
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Tidskriftsartikel (refereegranskat)abstract
- Missense and truncating variants in the X-chromosome-linked CLCN4 gene, resulting in reduced or complete loss-of-function (LOF) of the encoded chloride/proton exchanger ClC-4, were recently demonstrated to cause a neurocognitive phenotype in both males and females. Through international clinical matchmaking and interrogation of public variant databases we assembled a database of 90 rare CLCN4 missense variants in 90 families: 41 unique and 18 recurrent variants in 49 families. For 43 families, including 22 males and 33 females, we collated detailed clinical and segregation data. To confirm causality of variants and to obtain insight into disease mechanisms, we investigated the effect on electrophysiological properties of 59 of the variants in Xenopus oocytes using extended voltage and pH ranges. Detailed analyses revealed new pathophysiological mechanisms: 25% (15/59) of variants demonstrated LOF, characterized by a "shift" of the voltage-dependent activation to more positive voltages, and nine variants resulted in a toxic gain-of-function, associated with a disrupted gate allowing inward transport at negative voltages. Functional results were not always in line with in silico pathogenicity scores, highlighting the complexity of pathogenicity assessment for accurate genetic counselling. The complex neurocognitive and psychiatric manifestations of this condition, and hitherto under-recognized impacts on growth, gastrointestinal function, and motor control are discussed. Including published cases, we summarize features in 122 individuals from 67 families with CLCN4-related neurodevelopmental condition and suggest future research directions with the aim of improving the integrated care for individuals with this diagnosis.
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| 26. |
- Saha, Bivas, et al.
(författare)
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Compensation of native donor doping in ScN: Carrier concentration control and p-type ScN
- 2017
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Ingår i: Applied Physics Letters. - : AMER INST PHYSICS. - 0003-6951 .- 1077-3118. ; 110:25
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Tidskriftsartikel (refereegranskat)abstract
- Scandium nitride (ScN) is an emerging indirect bandgap rocksalt semiconductor that has attracted significant attention in recent years for its potential applications in thermoelectric energy conversion devices, as a semiconducting component in epitaxial metal/semiconductor superlattices and as a substrate material for high quality GaN growth. Due to the presence of oxygen impurities and native defects such as nitrogen vacancies, sputter-deposited ScN thin-films are highly degenerate n-type semiconductors with carrier concentrations in the (1-6) x 10(20) cm(-3) range. In this letter, we show that magnesium nitride (MgxNy) acts as an efficient hole dopant in ScN and reduces the n-type carrier concentration, turning ScN into a p-type semiconductor at high doping levels. Employing a combination of high-resolution X-ray diffraction, transmission electron microscopy, and room temperature optical and temperature dependent electrical measurements, we demonstrate that p-type Sc1-xMgxN thin-film alloys (a) are substitutional solid solutions without MgxNy precipitation, phase segregation, or secondary phase formation within the studied compositional region, (b) exhibit a maximum hole-concentration of 2.2 x 10(20) cm(-3) and a hole mobility of 21 cm(2)/Vs, (c) do not show any defect states inside the direct gap of ScN, thus retaining their basic electronic structure, and (d) exhibit alloy scattering dominating hole conduction at high temperatures. These results demonstrate MgxNy doped p-type ScN and compare well with our previous reports on p-type ScN with manganese nitride (MnxNy) doping. Published by AIP Publishing.
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| 27. |
- Schroeder, Jeremy L., et al.
(författare)
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Bulk-Like Laminated Nitride Metal/Semiconductor Superlattices for Thermoelectric Devices
- 2014
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Ingår i: Journal of microelectromechanical systems. - : Institute of Electrical and Electronics Engineers (IEEE). - 1057-7157 .- 1941-0158. ; 23:3, s. 672-680
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Tidskriftsartikel (refereegranskat)abstract
- Bulk-like thermionic energy conversion devices have been fabricated from nanostructured nitride metal/semiconductor superlattices using a novel lamination process. 5-mu m thick (Hf0.5Zr0.5)N (6-nm)/ScN (6-nm) metal/semiconductor superlattices with a 12 nm period were deposited on 100-silicon substrates by reactive magnetron sputtering followed by a selective tetra methyl ammonium hydroxide substrate etching and a gold-gold lamination process to yield 300 mu m x 300 mu m x 290 mu m microscale thermionic energy conversion elements with 16,640 superlattice periods. The thermionic element had a Seebeck coefficient of -120 mu V/K at 800 K, an electrical conductivity of similar to 2500 Omega(-1)m(-1) at 800 K, and a thermal conductivity of 2.9 and 4.3 W/m-K at 300 and 625 K, respectively. The temperature dependence of the Seebeck coefficient from 300 to 800 K suggests a parallel parasitic conduction path that is dominant at low temperature, and the temperature independent electrical conductivity indicates that the (Hf0.5Zr0.5)N/gold interface contact resistivity currently dominates the device. The thermal conductivity of the laminate was significantly lower than the thermal conductivity of the individual metal or semiconductor layers, indicating the beneficial effect of the metal/semiconductor interfaces toward lowering the thermal conductivity. The described lamination process effectively bridges the gap between the nanoscale requirements needed to enhance the thermoelectric figure of merit ZT and the microscale requirements of real-world devices.
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- Siegel, Corey A., et al.
(författare)
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Development of an index to define overall disease severity in IBD
- 2018
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Ingår i: Gut. - London, United Kingdom : BMJ Publishing Group Ltd. - 0017-5749 .- 1468-3288. ; 67:2, s. 244-254
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Tidskriftsartikel (refereegranskat)abstract
- Background and aim: Disease activity for Crohn's disease (CD) and UC is typically defined based on symptoms at a moment in time, and ignores the long-term burden of disease. The aims of this study were to select the attributes determining overall disease severity, to rank the importance of and to score these individual attributes for both CD and UC.Methods: Using a modified Delphi panel, 14 members of the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) selected the most important attributes related to IBD. Eighteen IOIBD members then completed a statistical exercise (conjoint analysis) to create a relative ranking of these attributes. Adjusted utilities were developed by creating proportions for each level within an attribute.Results: For CD, 15.8% of overall disease severity was attributed to the presence of mucosal lesions, 10.9% to history of a fistula, 9.7% to history of abscess and 7.4% to history of intestinal resection. For UC, 18.1% of overall disease severity was attributed to mucosal lesions, followed by 14.0% for impact on daily activities, 11.2% C reactive protein and 10.1% for prior experience with biologics. Overall disease severity indices were created on a 100-point scale by applying each attribute's average importance to the adjusted utilities.Conclusions: Based on specialist opinion, overall CD severity was associated more with intestinal damage, in contrast to overall UC disease severity, which was more dependent on symptoms and impact on daily life. Once validated, disease severity indices may provide a useful tool for consistent assessment of overall disease severity in patients with IBD.
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