| 1. |
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- 2019
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Tidskriftsartikel (refereegranskat)
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| 2. |
- Barrio, Isabel C., et al.
(författare)
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Background invertebrate herbivory on dwarf birch (Betula glandulosa-nana complex) increases with temperature and precipitation across the tundra biome
- 2017
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Ingår i: Polar Biology. - : Springer. - 0722-4060 .- 1432-2056. ; 40:11, s. 2265-2278
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Tidskriftsartikel (refereegranskat)abstract
- Chronic, low intensity herbivory by invertebrates, termed background herbivory, has been understudied in tundra, yet its impacts are likely to increase in a warmer Arctic. The magnitude of these changes is however hard to predict as we know little about the drivers of current levels of invertebrate herbivory in tundra. We assessed the intensity of invertebrate herbivory on a common tundra plant, the dwarf birch (Betula glandulosa-nana complex), and investigated its relationship to latitude and climate across the tundra biome. Leaf damage by defoliating, mining and gall-forming invertebrates was measured in samples collected from 192 sites at 56 locations. Our results indicate that invertebrate herbivory is nearly ubiquitous across the tundra biome but occurs at low intensity. On average, invertebrates damaged 11.2% of the leaves and removed 1.4% of total leaf area. The damage was mainly caused by external leaf feeders, and most damaged leaves were only slightly affected (12% leaf area lost). Foliar damage was consistently positively correlated with mid-summer (July) temperature and, to a lesser extent, precipitation in the year of data collection, irrespective of latitude. Our models predict that, on average, foliar losses to invertebrates on dwarf birch are likely to increase by 6-7% over the current levels with a 1 degrees C increase in summer temperatures. Our results show that invertebrate herbivory on dwarf birch is small in magnitude but given its prevalence and dependence on climatic variables, background invertebrate herbivory should be included in predictions of climate change impacts on tundra ecosystems.
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| 3. |
- Barrio, Isabel C., et al.
(författare)
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Publisher Correction to : Background invertebrate herbivory on dwarf birch (Betula glandulosa-nana complex) increases with temperature and precipitation across the tundra biome (vol 40, pg 2265, 2017)
- 2018
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Ingår i: Polar Biology. - : Springer. - 0722-4060 .- 1432-2056. ; 41:8, s. 1653-1654
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Tidskriftsartikel (refereegranskat)abstract
- The above mentioned article was originally scheduled for publication in the special issue on Ecology of Tundra Arthropods with guest editors Toke T. Hoye . Lauren E. Culler. Erroneously, the article was published in Polar Biology, Volume 40, Issue 11, November, 2017. The publisher sincerely apologizes to the guest editors and the authors for the inconvenience caused.
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| 4. |
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| 5. |
- Deijen, Charlotte L., et al.
(författare)
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Ten-year outcomes of a randomised trial of laparoscopic versus open surgery for colon cancer
- 2017
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Ingår i: Surgical Endoscopy. - : SPRINGER. - 0930-2794 .- 1432-2218. ; 31:6, s. 2607-2615
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Tidskriftsartikel (refereegranskat)abstract
- Laparoscopic surgery for colon cancer is associated with improved recovery and similar cancer outcomes at 3 and 5 years in comparison with open surgery. However, long-term survival rates have rarely been reported. Here, we present survival and recurrence rates of the Dutch patients included in the COlon cancer Laparoscopic or Open Resection (COLOR) trial at 10-year follow-up. Between March 1997 and March 2003, patients with non-metastatic colon cancer were recruited by 29 hospitals in eight countries and randomised to either laparoscopic or open surgery. Main inclusion criterion for the COLOR trial was solitary adenocarcinoma of the left or right colon. The primary outcome was disease-free survival at 3 years, and secondary outcomes included overall survival and recurrence. The 10-year follow-up data of all Dutch patients were collected. Analysis was by intention-to-treat. The trial was registered at ClinicalTrials.gov (NCT00387842). In total, 1248 patients were randomised, of which 329 were Dutch. Fifty-eight Dutch patients were excluded and 15 were lost to follow-up, leaving 256 patients for 10-year analysis. Median follow-up was 112 months. Disease-free survival rates were 45.2 % in the laparoscopic group and 43.2 % in the open group (difference 2.0 %; 95 % confidence interval (CI) -10.3 to 14.3; p = 0.96). Overall survival rates were 48.4 and 46.7 %, respectively (difference 1.7 %; 95 % CI -10.6 to 14.0; p = 0.83). Stage-specific analysis revealed similar survival rates for both groups. Sixty-two patients were diagnosed with recurrent disease, accounting for 29.4 % in the laparoscopic group and 28.2 % in the open group (difference 1.2 %; 95 % CI -11.1 to 13.5; p = 0.73). Seven patients had port- or wound-site recurrences (laparoscopic n = 3 vs. open n = 4). Laparoscopic surgery for non-metastatic colon cancer is associated with similar rates of disease-free survival, overall survival and recurrences as open surgery at 10-year follow-up.
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| 6. |
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| 7. |
- 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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| 8. |
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Agrarhistoria på många sätt : 28 studier om människan och jorden. Festskrift till Janken Myrdal på hans 60-årsdag
- 2009
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Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- Den överväldigande majoriteten av alla människor har varit verksamma i arbetet med jord och skog. Än idag är detta helt nödvändigt för vår överlevnad. Idag ställs även krav på landskapets biologiska och estetiska värden. Allt talar för att vi är i stort behov av agrarhistorisk kunskap. Boken ökar vår kunskap om dess kärna - om jorden, djuren och redskapen - men även de sociala, kulturella och politiska förhållandena som påverkat jordbruket. Bokens alla författare, både svenska och utländska, gör oss medvetna om mängden av agrarhistoriska källor och metoder. denna stora antologi är tillägnad Janken Myrdal, agrarhistoriens främste representant i Sverige, som låtit de mest skiftande och överraskande källmaterial och metoder komma till användning i sitt arbete.
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| 9. |
- Ahmad, Irma, et al.
(författare)
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High prevalence of persistent symptoms and reduced health-related quality of life 6 months after COVID-19
- 2023
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Ingår i: Frontiers in Public Health. - : Frontiers Media S.A.. - 2296-2565. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The long-term sequelae after COVID-19 constitute a challenge to public health and increased knowledge is needed. We investigated the prevalence of self-reported persistent symptoms and reduced health-related quality of life (HRQoL) in relation to functional exercise capacity, 6 months after infection, and explored risk factors for COVID-19 sequalae.METHODS: This was a prospective, multicenter, cohort study including 434 patients. At 6 months, physical exercise capacity was assessed by a 1-minute sit-to-stand test (1MSTST) and persistent symptoms were reported and HRQoL was evaluated through the EuroQol 5-level 5-dimension (EQ-5D-5L) questionnaire. Patients with both persistent symptoms and reduced HRQoL were classified into a new definition of post-acute COVID syndrome, PACS+. Risk factors for developing persistent symptoms, reduced HRQoL and PACS+ were identified by multivariable Poisson regression.RESULTS: Persistent symptoms were experienced by 79% of hospitalized, and 59% of non-hospitalized patients at 6 months. Hospitalized patients had a higher prevalence of self-assessed reduced overall health (28 vs. 12%) and PACS+ (31 vs. 11%). PACS+ was associated with reduced exercise capacity but not with abnormal pulse/desaturation during 1MSTST. Hospitalization was the most important independent risk factor for developing persistent symptoms, reduced overall health and PACS+.CONCLUSION: Persistent symptoms and reduced HRQoL are common among COVID-19 survivors, but abnormal pulse and peripheral saturation during exercise could not distinguish patients with PACS+. Patients with severe infection requiring hospitalization were more likely to develop PACS+, hence these patients should be prioritized for clinical follow-up after COVID-19.
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| 10. |
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| 11. |
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| 12. |
- Anderson, Johan, et al.
(författare)
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Applying uncertainty quantification in modelling of a steel beam exposed to fire
- 2016
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Ingår i: Structures in Fire. - 9781605953205 ; , s. 925-932
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Modelling of structures exposed to fires is prone to be heavily influenced by uncertainties in geometrical parameters, thermal material data as well as uncertainties in the boundary conditions. Assessing the effects and influences in variations of all the uncertain parameters is often cumbersome and traditional methods are impractical thus modelling of the total uncertainty is needed. Uncertainty Quantification with deterministic sampling is one possible way ahead to accommodate and evaluating the effects of uncertainties with as few repeated simulations as possible. In this paper the uncertainties stemming from error in the input data and boundary conditions on one example of a steel beam under four point bending exposed to fire is evaluated.
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| 13. |
- Anderson, Johan, et al.
(författare)
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Modelling in WFDS of a Wildfire Scenario
- 2016
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Ingår i: Book of Abstracts Nordic Fire & Safety Days 2016. ; , s. 33-33
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 14. |
- Anderson, Johan, et al.
(författare)
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Modelling in wfds of a wildfire scenario
- 2017
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Ingår i: 15th International Conference and Exhibition on Fire and Materials 2017. - : Interscience Communications Ltd. - 9781510846746 ; , s. 765-776
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Konferensbidrag (refereegranskat)abstract
- In this paper a coarse graining process is used to subsequently model large wildland fires, starting from a model of a single tree. The models are created using Wildland Urban Interface Fire dynamics Simulator (WFDS), and it is here found that reasonable fire spread in small forests can be obtained although the results are quite dependent on grid resolution as well as moisture content. In most realistic scenarios the computational volume is rather large yielding massive amounts of data. In using WFDS a rather small grid size is needed to appropriately model the fire spread this will be a severely limiting factor in creating large models.
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| 15. |
- Ayyer, Kartik, et al.
(författare)
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3D diffractive imaging of nanoparticle ensembles using an x-ray laser
- 2021
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Ingår i: Optica. - : Optical Society of America. - 2334-2536. ; 8:1, s. 15-23
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Tidskriftsartikel (refereegranskat)abstract
- Single particle imaging at x-ray free electron lasers (XFELs) has the potential to determine the structure and dynamics of single biomolecules at room temperature. Two major hurdles have prevented this potential from being reached, namely, the collection of sufficient high-quality diffraction patterns and robust computational purification to overcome structural heterogeneity. We report the breaking of both of these barriers using gold nanoparticle test samples, recording around 10 million diffraction patterns at the European XFEL and structurally and orientationally sorting the patterns to obtain better than 3-nm-resolution 3D reconstructions for each of four samples. With these new developments, integrating advancements in x-ray sources, fast-framing detectors, efficient sample delivery, and data analysis algorithms, we illuminate the path towards sub-nano meter biomolecular imaging. The methods developed here can also be extended to characterize ensembles that are inherently diverse to obtain their full structural landscape. Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License.
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| 16. |
- Azhar, Najia, et al.
(författare)
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Laparoscopic lavage for Hinchey III perforated diverticulitis : factors for treatment failure in two randomized clinical trials
- 2023
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Ingår i: The British journal of surgery. - 1365-2168. ; 110:7, s. 846-851
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The Scandinavian Diverticulitis (SCANDIV) trial and the LOLA arm of the LADIES trial randomized patients with Hinchey III perforated diverticulitis to laparoscopic peritoneal lavage or sigmoid resection. The aim of this analysis was to identify risk factors for treatment failure in patients with Hinchey III perforated diverticulitis.METHODS: This was a post hoc analysis of the SCANDIV trial and LOLA arm. Treatment failure was defined as morbidity requiring general anaesthesia (Clavien-Dindo grade IIIb or higher) within 90 days. Age, sex, BMI, ASA fitness grade, smoking status, previous episodes of diverticulitis, previous abdominal surgery, time to surgery, and surgical competence were all tested in univariable and multivariable logistic regression analyses using an interaction variable.RESULTS: The pooled analysis included 222 patients randomized to laparoscopic lavage and primary resection (116 and 106 patients respectively). Univariable analysis found ASA grade to be associated with advanced morbidity in both groups, and the following factors in the laparoscopic lavage group: smoking, corticosteroid use, and BMI. Significant factors for laparoscopic lavage morbidity in multivariable analysis were smoking (OR 7.05, 95 per cent c.i. 2.07 to 23.98; P = 0.002) and corticosteroid use (OR 6.02, 1.54 to 23.51; P = 0.010).CONCLUSION: Active smoking status and corticosteroid use were risk factors for laparoscopic lavage treatment failure (advanced morbidity) in patients with perforated diverticulitis.
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| 17. |
- Bartlett, AI, et al.
(författare)
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Uncertainty Quantification Applied to a Fire-Exposed Glued-Laminated Timber Beam
- 2016
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Ingår i: 14th International Probabilistic Workshop. - Cham : Springer. ; , s. 203-213
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- As a natural material, the response of timber structures under normal conditions and to fire is subject to wide variability. Deterministic models therefore struggle to reflect the reality of the response of timber since small variations in input influence the output significantly. However it is relatively straightforward to quantify uncertainties in model inputs in order to determine the uncertainties in the model response by employing uncertainty quantification (UQ) techniques. UQ of structural response to fire traditionally employs Monte Carlo techniques (Eamon and Jensen 2013) which are computationally expensive for a large number of variables. Deterministic Sampling (DS) (Hessling 2013) is a relatively new efficient alternative method for UQ. DS assumes that a continuous probability density function can be replaced by an ensemble of discrete deterministic samples if the two representations have the same statistical moments. DS has been demonstrated applied to, e.g. CFD simulations (Anderson et al. 2016). This paper applies DS techniques to study glued-laminated (glulam) timber in fire. Results are compared with random sampling techniques to show the validity of this method in this application.
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| 18. |
- Björsell, Tove, et al.
(författare)
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Risk factors for impaired respiratory function post COVID-19 : A prospective cohort study of nonhospitalized and hospitalized patients
- 2023
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Ingår i: Journal of Internal Medicine. - : Wiley-Blackwell Publishing Inc.. - 0954-6820 .- 1365-2796. ; 293:5, s. 600-614
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Severe COVID-19 increases the risk for long-term respiratory impairment, but data after mild COVID-19 are scarce. Our aims were to determine risk factors for reduced respiratory function 3-6 months after COVID-19 infection and to investigate if reduced respiratory function would relate to impairment of exercise performance and breathlessness.METHODS: Patients with COVID-19 were enrolled at the University Hospitals of Umeå and Örebro, and Karlstad Central Hospital, Sweden. Disease severity was defined as mild (nonhospitalized), moderate (hospitalized with or without oxygen treatment), and severe (intensive care). Spirometry, including diffusion capacity (DLCO ), was performed 3-6 months after hospital discharge or study enrollment (for nonhospitalized patients). Breathlessness (defined as ≥1 according to the modified Medical Research Council scale) and functional exercise capacity (1-min sit-to-stand test; 1-MSTST) were assessed.RESULTS: Between April 2020 and May 2021, 337 patients were enrolled in the study. Forced vital capacity and DLCO were significantly lower in patients with severe COVID-19. Among hospitalized patients, 20% had reduced DLCO , versus 4% in nonhospitalized. Breathlessness was found in 40.6% of the participants and was associated with impaired DLCO . A pathological desaturation or heart rate response was observed in 17% of participants during the 1-MSTST. However, this response was not associated with reduced DLCO .CONCLUSION: Reduced DLCO was the major respiratory impairment 3-6 months following COVID-19, with hospitalization as the most important risk factor. The lack of association between impaired DLCO and pathological physiological responses to exertion suggests that these physiological responses are not primarily related to decreased lung function.
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| 19. |
- Byström, Alexandra, et al.
(författare)
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Large scale test on a steel column exposed to localized fire
- 2014
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Ingår i: Journal of Structural Fire Engineering. - : Emerald. - 2040-2317 .- 2040-2325. ; 5:2, s. 147-160
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Tidskriftsartikel (refereegranskat)abstract
- A localized fire is a fire which in a compartment is unlikely to reach flash-over and uniform temperature distribution. Designing for localized fires is generally more difficult than for flash-over compartment fires because of the complexity of the problem. There is also a lack of experimental data. We report here on a full scale test series on a steel column exposed to localized fires. The setup is a 6 meters tall hollow circular column, ϕ = 200 mm with a steel thickness of 10 mm. The unloaded column was hanging centrally above different pool fires. Temperatures of gas and steel were measured by thermocouples, and adiabatic surface temperatures at the steel surface were measured by plate thermometers of various designs. The results are compared with estimates based on Eurocode 1991-1-2 which in all cases studied overestimate the thermal impact for this setup. The input from plate thermometers was used to compute the steel temperatures using finite element methods. Excellent agreement was found if the radiation exchange within the column due to asymmetry of the exposure was taken into account.
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| 20. |
- Carow, Berit, et al.
(författare)
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Immune mapping of human tuberculosis and sarcoidosis lung granulomas
- 2024
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Ingår i: FRONTIERS IN IMMUNOLOGY. - 1664-3224. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- Tuberculosis (TB) and sarcoidosis are both granulomatous diseases. Here, we compared the immunological microenvironments of granulomas from TB and sarcoidosis patients using in situ sequencing (ISS) transcriptomic analysis and multiplexed immunolabeling of tissue sections. TB lesions consisted of large necrotic and cellular granulomas, whereas "multifocal" granulomas with macrophages or epitheloid cell core and a T-cell rim were observed in sarcoidosis samples. The necrotic core in TB lesions was surrounded by macrophages and encircled by a dense T-cell layer. Within the T-cell layer, compact B-cell aggregates were observed in most TB samples. These B-cell clusters were vascularized and could contain defined B-/T-cell and macrophage-rich areas. The ISS of 40-60 immune transcripts revealed the enriched expression of transcripts involved in homing or migration to lymph nodes, which formed networks at single-cell distances in lymphoid areas of the TB lesions. Instead, myeloid-annotated regions were enriched in CD68, CD14, ITGAM, ITGAX, and CD4 mRNA. CXCL8 and IL1B mRNA were observed in granulocytic areas in which M. tuberculosis was also detected. In line with ISS data indicating tertiary lymphoid structures, immune labeling of TB sections expressed markers of high endothelial venules, follicular dendritic cells, follicular helper T cells, and lymph-node homing receptors on T cells. Neither ISS nor immunolabeling showed evidence of tertiary lymphoid aggregates in sarcoidosis samples. Together, our finding suggests that despite their heterogeneity, the formation of tertiary immune structures is a common feature in granulomas from TB patients.
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| 21. |
- Clark, Alice, et al.
(författare)
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Sleep Impairment and Prognosis of Acute Myocardial Infarction : A Prospective Cohort Study
- 2014
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Ingår i: Sleep. - : Oxford University Press (OUP). - 0161-8105 .- 1550-9109. ; 37:5, s. 851-U215
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Tidskriftsartikel (refereegranskat)abstract
- Study Objectives: Impaired sleep is an established risk factor for the development of cardiovascular disease, whereas less is known about how impaired sleep affects cardiovascular prognosis. The aim of this study is to determine how different aspects of impaired sleep affect the risk of case fatality and subsequent cardiovascular events following first-time acute myocardial infarction (AMI). Design: Prospective cohort study. Setting: The Stockholm Heart Epidemiology Program, Sweden. Participants: There were 2,246 first-time AMI cases. Measurements and Results: Sleep impairment was assessed by the Karolina Sleep Questionnaire, which covers various indices of impaired sleep: disturbed sleep, impaired awakening, daytime sleepiness, and nightmares. Case fatality, defined as death within 28 days of initial AMI, and new cardiovascular events within up to 10 y of follow-up were identified through national registries. In women, disturbed sleep showed a consistently higher risk of long-term cardiovascular events: AMI (hazard ratio [HR] = 1.69; 95% confidence interval [CI] 0.95-3.00), stroke (HR = 2.61; 95% CI: 1.19-5.76), and heart failure (HR = 2.43; 95% CI: 1.18-4.97), whereas no clear effect of impaired sleep on case fatality was found in women. In men, a strong effect on case fatality (odds ratio = 3.27; 95% CI: 1.76-6.06) was observed in regard to impaired awakening; however, no consistent effect of impaired sleep was seen on long-term cardiovascular prognosis. Conclusion: Results suggest sex-specific effects of impaired sleep that differ by short-and long-term prognosis. Sleep complaints are frequent, easily recognizable, and potentially manageable. Evaluation of sleep complaints may, even if they represent prognostic markers rather than risk factors, provide additional information in clinical risk assessment that could benefit secondary cardiovascular prevention.
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| 22. |
- Cuapio, Angelica, et al.
(författare)
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NK cell frequencies, function and correlates to vaccine outcome in BNT162b2 mRNA anti-SARS-CoV-2 vaccinated healthy and immunocompromised individuals
- 2022
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Ingår i: Molecular Medicine. - : BioMed Central (BMC). - 1076-1551 .- 1528-3658. ; 28:1
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Tidskriftsartikel (refereegranskat)abstract
- Adaptive immune responses have been studied extensively in the course of mRNA vaccination against COVID-19. Considerably fewer studies have assessed the effects on innate immune cells. Here, we characterized NK cells in healthy individuals and immunocompromised patients in the course of an anti-SARS-CoV-2 BNT162b2 mRNA prospective, open-label clinical vaccine trial. See trial registration description in notes. Results revealed preserved NK cell numbers, frequencies, subsets, phenotypes, and function as assessed through consecutive peripheral blood samplings at 0, 10, 21, and 35 days following vaccination. A positive correlation was observed between the frequency of NKG2C+ NK cells at baseline (Day 0) and anti-SARS-CoV-2 Ab titers following BNT162b2 mRNA vaccination at Day 35. The present results provide basic insights in regards to NK cells in the context of mRNA vaccination, and have relevance for future mRNA-based vaccinations against COVID-19, other viral infections, and cancer.Trial registration: The current study is based on clinical material from the COVAXID open-label, non-randomized prospective clinical trial registered at EudraCT and clinicaltrials.gov (no. 2021–000175-37). Description: https://clinicaltrials.gov/ct2/show/NCT04780659?term=2021-000175-37&draw=2&rank=1.
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| 23. |
- Dall'Osto, Manuel, et al.
(författare)
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Simultaneous measurements of aerosol size distributions at three sites in the European high Arctic
- 2019
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Ingår i: Atmospheric Chemistry And Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 19:11, s. 7377-7395
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Tidskriftsartikel (refereegranskat)abstract
- Aerosols are an integral part of the Arctic climate system due to their direct interaction with radiation and indirect interaction through cloud formation. Understanding aerosol size distributions and their dynamics is crucial for the ability to predict these climate relevant effects. When of favourable size and composition, both long-rangetransported - and locally formed particles - may serve as cloud condensation nuclei (CCN). Small changes of composition or size may have a large impact on the low CCN concentrations currently characteristic of the Arctic environment. We present a cluster analysis of particle size distributions (PSDs; size range 8-500 nm) simultaneously collected from three high Arctic sites during a 3-year period (20132015). Two sites are located in the Svalbard archipelago: Zeppelin research station (ZEP; 474 m above ground) and the nearby Gruvebadet Observatory (GRU; about 2 km distance from Zeppelin, 67 m above ground). The third site (Villum Research Station at Station Nord, VRS; 30 m above ground) is 600 km west-northwest of Zeppelin, at the tip of northeastern Greenland. The GRU site is included in an inter-site comparison for the first time. K-means cluster analysis pro- vided eight specific aerosol categories, further combined into broad PSD classes with similar characteristics, namely pristine low concentrations (12 %-14 % occurrence), new particle formation (16 %-32 %), Aitken (21 %-35 %) and accumulation (20 %-50 %). Confined for longer time periods by consolidated pack sea ice regions, the Greenland site GRU shows PSDs with lower ultrafine-mode aerosol concentrations during summer but higher accumulation-mode aerosol concentrations during winter, relative to the Svalbard sites. By association with chemical composition and cloud condensation nuclei properties, further conclusions can be derived. Three distinct types of accumulation-mode aerosol are observed during winter months. These are associated with sea spray (largest detectable sizes, > 400 nm), Arctic haze (main mode at 150 nm) and aged accumulation-mode (main mode at 220 nm) aerosols. In contrast, locally produced particles, most likely of marine biogenic origin, exhibit size distributions dominated by the nucleation and Aitken mode during summer months. The obtained data and analysis point towards future studies, including apportioning the relative contribution of primary and secondary aerosol formation processes and elucidating anthropogenic aerosol dynamics and transport and removal processes across the Greenland Sea. In order to address important research questions in the Arctic on scales beyond a singular station or measurement events, it is imperative to continue strengthening international scientific cooperation.
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| 24. |
- Dankiewicz, Josef, et al.
(författare)
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Hypothermia versus Normothermia after Out-of-Hospital Cardiac Arrest
- 2021
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Ingår i: New England Journal of Medicine. - : MASSACHUSETTS MEDICAL SOC. - 0028-4793 .- 1533-4406. ; 384:24, s. 2283-2294
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Tidskriftsartikel (refereegranskat)abstract
- Hypothermia or Normothermia after Cardiac Arrest This trial randomly assigned patients with coma after out-of-hospital cardiac arrest to undergo targeted hypothermia at 33 degrees C or normothermia with treatment of fever. At 6 months, there were no significant between-group differences regarding death or functional outcomes. Background Targeted temperature management is recommended for patients after cardiac arrest, but the supporting evidence is of low certainty. Methods In an open-label trial with blinded assessment of outcomes, we randomly assigned 1900 adults with coma who had had an out-of-hospital cardiac arrest of presumed cardiac or unknown cause to undergo targeted hypothermia at 33 degrees C, followed by controlled rewarming, or targeted normothermia with early treatment of fever (body temperature, >= 37.8 degrees C). The primary outcome was death from any cause at 6 months. Secondary outcomes included functional outcome at 6 months as assessed with the modified Rankin scale. Prespecified subgroups were defined according to sex, age, initial cardiac rhythm, time to return of spontaneous circulation, and presence or absence of shock on admission. Prespecified adverse events were pneumonia, sepsis, bleeding, arrhythmia resulting in hemodynamic compromise, and skin complications related to the temperature management device. Results A total of 1850 patients were evaluated for the primary outcome. At 6 months, 465 of 925 patients (50%) in the hypothermia group had died, as compared with 446 of 925 (48%) in the normothermia group (relative risk with hypothermia, 1.04; 95% confidence interval [CI], 0.94 to 1.14; P=0.37). Of the 1747 patients in whom the functional outcome was assessed, 488 of 881 (55%) in the hypothermia group had moderately severe disability or worse (modified Rankin scale score >= 4), as compared with 479 of 866 (55%) in the normothermia group (relative risk with hypothermia, 1.00; 95% CI, 0.92 to 1.09). Outcomes were consistent in the prespecified subgroups. Arrhythmia resulting in hemodynamic compromise was more common in the hypothermia group than in the normothermia group (24% vs. 17%, P<0.001). The incidence of other adverse events did not differ significantly between the two groups. Conclusions In patients with coma after out-of-hospital cardiac arrest, targeted hypothermia did not lead to a lower incidence of death by 6 months than targeted normothermia. (Funded by the Swedish Research Council and others; TTM2 ClinicalTrials.gov number, .)
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| 25. |
- Debuyser, Michael, et al.
(författare)
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Behaviour of monolithic and laminated glass exposed to radiant heating
- 2017
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Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 130, s. 212-229
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Tidskriftsartikel (refereegranskat)abstract
- Glass is seeing a growing interest as a structural material as a result of its relatively good strength to weight ratio and the obvious aesthetic benefits of its use in buildings. However due to the sensitivity of glass to thermal shock and the considerably temperature-dependent behaviour of interlayer materials as a result of their visco-elastic nature, the mechanical behaviour of laminated glass will be severely influenced by exposure to fire. Relatively little research has been conducted in the past to study the response of load bearing structural glass, and laminated glass in particular to radiant heating. This paper represents an effort to try to understand the effects of through depth radiation absorption and temperature conduction through laminated glass with a view to ultimately developing a model for studying load bearing glass exposed to elevated temperatures, such as those that would be expected in a fire. The paper reports on an experimental research programme in which several monolithic and laminated glass configurations were exposed to a radiant heat flux to study the different phenomena that occur upon exposure to fire conditions, including the ratios of absorbed, transmitted and reflected heat flux to the incident heat flux. The paper then presents a numerical heat transfer model which is developed based on these experimental results and that is able to determine the evolution of the temperature profile as a result of a given incident heat flux. The effectiveness of the heat transfer model is demonstrated through comparison with the temperatures measured during the experimental work.
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| 26. |
- Gao, Yu, et al.
(författare)
-
Immunodeficiency syndromes differentially impact the functional profile of SARS-CoV-2-specific T cells elicited by mRNA vaccination
- 2022
-
Ingår i: Immunity. - : Elsevier. - 1074-7613 .- 1097-4180. ; 55:9, s. 1732-1746.e5
-
Tidskriftsartikel (refereegranskat)abstract
- Many immunocompromised patients mount suboptimal humoral immunity after SARS-CoV-2 mRNA vaccination. Here, we assessed the single-cell profile of SARS-CoV-2-specific T cells post-mRNA vaccination in healthy individuals and patients with various forms of immunodeficiencies. Impaired vaccine-induced cell-mediated immunity was observed in many immunocompromised patients, particularly in solid-organ transplant and chronic lymphocytic leukemia patients. Notably, individuals with an inherited lack of mature B cells, i.e., X-linked agammaglobulinemia (XLA) displayed highly functional spike-specific T cell responses. Single-cell RNA-sequencing further revealed that mRNA vaccination induced a broad functional spectrum of spike-specific CD4+ and CD8+ T cells in healthy individuals and patients with XLA. These responses were founded on polyclonal repertoires of CD4+ T cells and robust expansions of oligoclonal effector-memory CD45RA+ CD8+ T cells with stem-like characteristics. Collectively, our data provide the functional continuum of SARS-CoV-2-specific T cell responses post-mRNA vaccination, highlighting that cell-mediated immunity is of variable functional quality across immunodeficiency syndromes.
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| 27. |
- George, Jan Peter, et al.
(författare)
-
Method comparison of indirect assessments of understory leaf area index (LAIu) : A case study across the extended network of ICOS forest ecosystem sites in Europe
- 2021
-
Ingår i: Ecological Indicators. - : Elsevier BV. - 1470-160X .- 1872-7034. ; 128
-
Tidskriftsartikel (refereegranskat)abstract
- Leaf area index (LAI) is a key ecological indicator for describing the structure of canopies and for modelling energy exchange between atmosphere and biosphere. While LAI of the forest overstory can be accurately assessed over large spatial scales via remote sensing, LAI of the forest understory (LAIu) is still largely ignored in ecological studies and ecosystem modelling due to the fact that it is often too complex to be destructively sampled or approximated by other site parameters. Additionally, so far only few attempts have been made to retrieve understory LAI via remote sensing, because dense canopies with high LAI are often hindering retrieval algorithms to produce meaningful estimates for understory LAI. Consequently, the forest understory still constitutes a poorly investigated research realm impeding ecological studies to properly account for its contribution to the energy absorption capacity of forest stands. This study aims to compare three conceptually different indirect retrieval methodologies for LAIu over a diverse panel of forest understory types distributed across Europe. For this we carried out near-to-surface measurements of understory reflectance spectra as well as digital surface photography over the extended network of Integrated Carbon Observation System (ICOS) forest ecosystem sites. LAIu was assessed by exploiting the empirical relationship between vegetation cover and light absorption (Beer-Lambert- Bouguer law) as well as by utilizing proposed relationships with two prominent vegetation indices: normalized difference vegetation index (NDVI) and simple ratio (SR). Retrievals from the three methods were significantly correlated with each other (r = 0.63–0.99, RMSE = 0.53–0.72), but exhibited also significant bias depending on the LAI scale. The NDVI based retrieval approach most likely overestimates LAI at productive sites when LAIu > 2, while the simple ratio algorithm overestimates LAIu at sites with sparse understory vegetation and presence of litter or bare soil. The purely empirical method based on the Beer-Lambert law of light absorption seems to offer a good compromise, since it provides reasonable LAIu values at both low and higher LAI ranges. Surprisingly, LAIu variation among sites seems to be largely decoupled from differences in climate and light permeability of the overstory, but significantly increased with vegetation diversity (expressed as species richness) and hence proposes new applications of LAIu in ecological modelling.
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| 28. |
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| 29. |
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| 30. |
- Gorski, Mathias, et al.
(författare)
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Genetic loci and prioritization of genes for kidney function decline derived from a meta-analysis of 62 longitudinal genome-wide association studies
- 2022
-
Ingår i: Kidney International. - : Elsevier. - 0085-2538 .- 1523-1755. ; 102:3, s. 624-639
-
Tidskriftsartikel (refereegranskat)abstract
- Estimated glomerular filtration rate (eGFR) reflects kidney function. Progressive eGFR-decline can lead to kidney failure, necessitating dialysis or transplantation. Hundreds of loci from genome-wide association studies (GWAS) for eGFR help explain population cross section variability. Since the contribution of these or other loci to eGFR-decline remains largely unknown, we derived GWAS for annual eGFR-decline and meta-analyzed 62 longitudinal studies with eGFR assessed twice over time in all 343,339 individuals and in high-risk groups. We also explored different covariate adjustment. Twelve genomewide significant independent variants for eGFR-decline unadjusted or adjusted for eGFR- baseline (11 novel, one known for this phenotype), including nine variants robustly associated across models were identified. All loci for eGFR-decline were known for cross-sectional eGFR and thus distinguished a subgroup of eGFR loci. Seven of the nine variants showed variant- by-age interaction on eGFR cross section (further about 350,000 individuals), which linked genetic associations for eGFR-decline with agedependency of genetic cross- section associations. Clinically important were two to four-fold greater genetic effects on eGFR-decline in high-risk subgroups. Five variants associated also with chronic kidney disease progression mapped to genes with functional in- silico evidence (UMOD, SPATA7, GALNTL5, TPPP). An unfavorable versus favorable nine-variant genetic profile showed increased risk odds ratios of 1.35 for kidney failure (95% confidence intervals 1.03- 1.77) and 1.27 for acute kidney injury (95% confidence intervals 1.08-1.50) in over 2000 cases each, with matched controls). Thus, we provide a large data resource, genetic loci, and prioritized genes for kidney function decline, which help inform drug development pipelines revealing important insights into the age-dependency of kidney function genetics.
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| 31. |
- Gray, Linsay, et al.
(författare)
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International differences in self-reported health measures in 33 major metropolitan areas in Europe
- 2012
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Ingår i: European Journal of Public Health. - : Oxford University Press (OUP). - 1101-1262 .- 1464-360X. ; 22:1, s. 40-47
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The increasing concentration of populations into large conurbations in recent decades has not been matched by international health assessments, which remain largely focused at the country level. We aimed to demonstrate the use of routine survey data to compare the health of large metropolitan centres across Europe and determine the extent to which differences are due to socio-economic factors.METHODS:Multilevel modelling of health survey data on 126 853 individuals from 33 metropolitan areas in the UK, Republic of Ireland, Sweden, Norway, Finland, Spain, Belgium and Germany compared general health, longstanding illness, acute sickness, psychological distress and obesity with the average for all areas, accounting for education and social class.RESULTS:We found some areas (Greater Glasgow; Greater Manchester, Cheshire and Merseyside; Northumberland, Tyne and Wear and South Yorkshire) had significantly higher levels of poor health. Other areas (West Flanders and Antwerp) had better than average health. Differences in individual socio-economic circumstances did not explain findings. With a few exceptions, acute sickness levels did not vary.CONCLUSION:Health tended to be worse in metropolitan areas in the north and west of the UK and the central belt and south east of Germany, and more favourable in Sweden and north west Belgium, even accounting for socio-economic composition of local populations. This study demonstrated that combining national health survey data covering different areas is viable but not without technical difficulties. Future comparisons between European regions should be made using standardized sampling, recruitment and data collection protocols, allowing proper monitoring of health inequalities.
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| 32. |
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| 33. |
- Honfi, Daniel, et al.
(författare)
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Behavior of load-bearing glass at elevated temperature
- 2018
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Ingår i: ce/papers. - : Wiley. - 2509-7075. ; 2:5-6, s. 533-540
-
Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT The use of glass as a structural material has increased in the built environment over the last decades. Despite the large number of research projects and studies, it still poses difficulties in structural design. This particularly applies to the behaviour of glass in fire and under elevated temperatures since the available data on temperature dependent mechanical and thermal properties of glass is still limited. This contribution provides a brief overview of material properties of glass at elevated temperature and elaborates on current requirements for the fire safety included in standards.
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| 34. |
- Kaya, Ibrahim, et al.
(författare)
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On-Tissue Chemical Derivatization of Catecholamines Using 4-(N-Methyl)pyridinium Boronic Acid for ToF-SIMS and LDI-ToF Mass Spectrometry Imaging
- 2018
-
Ingår i: Analytical Chemistry. - : American Chemical Society (ACS). - 0003-2700 .- 1520-6882. ; 90:22, s. 13580-13590
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Tidskriftsartikel (refereegranskat)abstract
- The analysis of small polar compounds with ToF-SIMS and MALDI-ToF-MS have been generally hindered by low detection sensitivity, poor ionization efficiency, ion suppression, analyte in-source fragmentation, and background spectral interferences from either a MALDI matrix and/or endogenous tissue components. Chemical derivatization has been a well-established strategy for improved mass spectrometric detection of many small molecular weight endogenous compounds in tissues. Here, we present a devised strategy to selectively derivatize and sensitively detect catecholamines with both secondary ion ejection and laser desorption ionization strategies, which are used in many imaging mass spectrometry (IMS) experiments. Chemical derivatization of catecholamines was performed by a reaction with a synthesized permanent pyridinium-cation-containing boronic acid molecule, 4-(N-methyl)pyridinium boronic acid, through boronate ester formation (boronic acid-diol reaction). The derivatization facilitates their sensitive detection with ToF-SIMS and LDI-ToF mass spectrometric techniques. 4-(N-Methyl)pyridinium boronic acid worked as a reactive matrix for catecholamines with LDI and improved the sensitivity of detection for both SIMS and LDI, while the isotopic abundances of the boron atom reflect a unique isotopic pattern for derivatized catecholamines in MS analysis. Finally, the devised strategy was applied, as a proof of concept, for on-tissue chemical derivatization and GCIB-ToF-SIMS (down to 3 μm per pixel spatial resolution) and LDI-ToF mass spectrometry imaging of dopamine, epinephrine, and norepinephrine in porcine adrenal gland tissue sections. MS/MS using collision-induced dissociation (CID)-ToF-ToF-SIMS was subsequently employed on the same tissue sections after SIMS and LDI mass spectrometry imaging experiments, which provided tandem MS information for the validation of the derivatized catecholamines in situ. This methodology can be a powerful approach for the selective and sensitive ionization/detection and spatial localization of diol-containing molecules such as aminols, vic-diols, saccharides, and glycans along with catecholamines in tissue sections with both SIMS and LDI/MALDI-MS techniques. © 2018 American Chemical Society.
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| 35. |
- Kaya, Ibrahim, et al.
(författare)
-
Spatial Lipidomics Reveals Region and Long Chain Base Specific Accumulations of Monosialogangliosides in Amyloid Plaques in Familial Alzheimer's Disease Mice (5xFAD) Brain
- 2020
-
Ingår i: ACS Chemical Neuroscience. - : American Chemical Society (ACS). - 1948-7193. ; 11:1, s. 14-24
-
Tidskriftsartikel (refereegranskat)abstract
- Ganglioside metabolism is significantly altered in Alzheimer's disease (AD), which is a progressive neuro-degenerative disease prominently characterized by one of its pathological hallmarks, amyloid deposits or "senile plaques". While the plaques mainly consist of aggregated variants of amyloid-beta protein (A beta), recent studies have revealed a number of lipid species including gangliosides in amyloid plaques along with A beta peptides. It has been widely suggested that long chain (sphingosine) base (LCBs), C18:1-LCB and C20:1-LCB, containing gangliosides might play different roles in neuronal function in vivo. In order to elucidate region-specific aspects of amyloid-plaque associated C18:1-LCB and C20:1-LCB ganglioside accumulations, high spatial resolution (10 mu m per pixel) matrix assisted laser desorption ionization imaging mass spectrometry (MALDI-IMS) of gangliosides in amyloid plaques was performed in hippocampal and adjacent cortical regions of 12 month old 5xFAD mouse coronal brain sections from two different stereotaxic coordinates (bregma points, -2.2 and -2.7 mm). MALDI-IMS uncovered brain-region (2 and 3D) and/or LCB specific accumulations of monosialogangliosides (GMs): GM1, GM2, and GM3 in the hippocampal and cortical amyloid plaques. The results reveal monosialogangliosides to be an important component of amyloid plaques and the accumulation of different gangliosides is region and LCB specific in 12 month old 5xFAD mouse brain. This is discussed in relation to amyloid-associated AD pathogenesis such as lipid related immune changes in amyloid plaques, AD specific ganglioside metabolism, and, notably, AD-associated impaired neurogenesis in the subgranular zone.
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| 36. |
- Lange, David, et al.
(författare)
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A Comparison of the Conditions in a Fire Resistance Furnace When Testing Combustible and Non-combustible Construction
- 2020
-
Ingår i: Fire technology. - : Springer. - 0015-2684 .- 1572-8099. ; 56:4, s. 1621-1654
-
Tidskriftsartikel (refereegranskat)abstract
- This paper reports on two experiments conducted in a fire resistance furnace to study the differences in the boundary conditions, the fire dynamics and the fuel required to run the furnace when a combustible timber specimen as opposed to a non-combustible concrete specimen is tested. In both experiments measurements were taken in the furnace to evaluate the difference in the environments of the furnace and the response of the elements being tested. These include non-control plate thermometers distributed throughout the furnace; O2, CO2 and CO gas measurements taken at different distances from the specimen surface and in the furnace exhaust; instrumentation of one of the bricks comprising the furnace lining with thermocouples at different depths from the exposed surface; and mass loss of the combustible timber specimen. Thermal exposure of elements in a furnace is discussed, as well as the impact of the different materials on the similarity of thermal exposure. This is done through analysis and discussion of the different measurements taken and the apparent influence of the specimen being tested on the boundary condition of the heat diffusion equation. We conclude that; (1) the fire dynamics in a furnace are dependent on the specimen being tested; (2) that the test with the combustible specimen requires less fuel flow to the burners such that the control plate thermometers follow the ISO 834 temperature–time curve compared to the non-combustible specimen, however that this is not only a result of the combustibility of the specimen but is also a consequence of the different thermal inertia of the two materials; (3) that the boundary condition for heat transfer to a test object in furnace tests is dependent on the properties of the specimen being tested; and (4) that the timber when placed on the furnace experiences smouldering combustion after the char layer has formed. A fire resistance test of combustible construction of a given period represents a significantly less onerous test in terms of energy absorbed or fuel made available than one of a non-combustible construction, implying that the existing fire resistance framework may not be appropriate for timber structures and that an alternative approach may be required.
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| 37. |
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| 38. |
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| 39. |
- Lange, David, et al.
(författare)
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Mechanical response of a partially restrained column exposed to localised fires
- 2014
-
Ingår i: Fire safety journal. - : Elsevier BV. - 0379-7112 .- 1873-7226. ; 67:Jul, s. 82-95
-
Tidskriftsartikel (refereegranskat)abstract
- Recent trends in structural fire engineering research have focussed on the response of buildings with large open plan spaces to so-called travelling fires. These fires travel horizontally across the floor plate of a building and result in time and spatially varying thermal exposure and response of the structure to the fire. What has received little attention, however, is the effect that non-uniform thermal exposure has on columns. Recent tests conducted at SP demonstrated the effect of a small non-uniformity of thermal exposure, resulting in a thermal gradient of around 1 °C/mm, on a column exposed to a pool fire. The curvature resulting from a non-uniform thermal exposure where the column is pinned, or in cases where the column is partially restrained, will result in an eccentricity in the column's loading and large second order effects. This paper describes the effect of thermal exposure varying in both the horizontal and vertical axes to columns by means of including this thermal boundary in a solution of classical Euler beam theory. The resulting solution allows for a variation in the stiffness of the rotational restraint at both ends of the column and a non-uniform temperature exposure through the column's section and along its height. The resulting equations help to understand better the impact of the assumptions of 'lumped capacitance' on steel columns, suggesting a challenge to this assumption in some instances, as well as to enhance understanding of the impact of non-uniform fires on steel columns.
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| 40. |
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| 41. |
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| 42. |
- Lange, Mark, 1958-, et al.
(författare)
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Capturing Quality Perceptions in the Design Rational of a Modular Product Concept
- 2001
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Ingår i: Design for Configuration: A Debate Based on the 5th Wdk Workshop on Product Structuring. - : Springer Berlin/Heidelberg. - 9783540677390 ; , s. 101-116
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The design of a product is a process of negotiating product knowledge represented in two general forms, 1) verbal and textual statements in a "design rationale" about a product and 2) models of a product using graphical modleing languages. The objective of this process is an artifact with which a user will interact, an interaction based on the use of our senses. The problem here is that, when considering the use of computer systems to support communication during integrated product development, the rationale behind the design, representing what is understood about a product lacks a quantifiable relationship to the models of a product. A approach to understand this problem can be found in the domain of semiotic sign theory, where product synthesis in design is treated as an act of semiosis. This approach is discussed in this paper in conjunction with product structuring supported by the method, Modular Function Deployment, the result of which is presented as a portion of a general theory of synthesis called Design Semiosis.
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| 43. |
- Lange, Vinzenz, et al.
(författare)
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Targeted quantitative analysis of Streptococcus pyogenes virulence factors by multiple reaction monitoring
- 2008
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Ingår i: Molecular & Cellular Proteomics. - 1535-9484. ; 7:8, s. 1489-1500
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Tidskriftsartikel (refereegranskat)abstract
- In many studies, particularly in the field of systems biology, it is essential that identical protein sets are precisely quantified in multiple samples such as those representing differentially perturbed cell states. The high degree of reproducibility required for such experiments has not been achieved by classical mass spectrometry-based proteomics methods. In this study we describe the implementation of a targeted quantitative approach by which predetermined protein sets are first identified and subsequently quantified at high sensitivity reliably in multiple samples. This approach consists of three steps. First, the proteome is extensively mapped out by multidimensional fractionation and tandem mass spectrometry, and the data generated are assembled in the PeptideAtlas database. Second, based on this proteome map, peptides uniquely identifying the proteins of interest, proteotypic peptides, are selected, and multiple reaction monitoring (MRM) transitions are established and validated by MS2 spectrum acquisition. This process of peptide selection, transition selection, and validation is supported by a suite of software tools, TIQAM (Targeted Identification for Quantitative Analysis by MRM), described in this study. Third, the selected target protein set is quantified in multiple samples by MRM. Applying this approach we were able to reliably quantify low abundance virulence factors from cultures of the human pathogen Streptococcus pyogenes exposed to increasing amounts of plasma. The resulting quantitative protein patterns enabled us to clearly define the subset of virulence proteins that is regulated upon plasma exposure.
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| 44. |
- Lushnikova, Alexandra, et al.
(författare)
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Altered levels of immune checkpoint molecules in colon biopsies and sera from microscopic colitis and ulcerative colitis patients compared to controls
- 2021
-
Ingår i: Journal of Immunology. - : American Association of Immunologists. - 0022-1767 .- 1550-6606. ; 206:Suppl.
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Background: Microscopic colitis (MC), comprising lymphocytic colitis (LC) and collagenous colitis (CC), is an inflammatory bowel disorder. MC patients have a lower risk of developing colorectal cancer (CRC) than ulcerative colitis (UC) patients. We hypothesize that the immune response in MC is geared more towards immune surveillance of tumor cells than that of UC, which instead contributes to inflammation-associated CRC.Methods: Using Luminex, protein levels of 14 immune checkpoints (TIM-3, CD28, CD137, CD27, CD152, HVEM, IDO, LAG-3, BTLA, GITR, CD80, PD-1, PD-L1, PD-L2) in protein lysates from colon biopsies (controls, n = 9; diarrhea controls, n = 7; LC, n = 14; CC, n = 15; UC, n = 17) were analyzed. Soluble checkpoints were analyzed in serum (23 controls, 17 LC, 36 CC and 2 UC).Results: In patients with active LC and CC, CD137, IDO, and CD80 levels were increased compared with one or both control groups. CD152 and PD-1 levels were increased in patients with active CC compared with both control groups. In patients with active UC, levels of CD137, CD152, BTLA, PD-1, and PD-L2 were increased compared with both control groups, IDO levels were increased compared with controls, and CD80 levels were raised compared with diarrhea controls.In sera, CD27, IDO, CD80, PD-1, and PD-L2 levels were decreased in LC patients compared to controls.Conclusions: Increased levels of immune checkpoint molecules in colon biopsies from UC and MC patients are likely a sign of inflammation and may indicate what kind of homeostatic feed-back mechanisms are active to balance inflammation. Lowered concentrations of soluble immune checkpoint molecules in sera from patients with LC indicate a different level of homeostatic balance systemically in LC patients versus controls.
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| 45. |
- Niessl, Julia, et al.
(författare)
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Identification of resident memory CD8+ T cells with functional specificity for SARS-CoV-2 in unexposed oropharyngeal lymphoid tissue
- 2021
-
Ingår i: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 6:64
-
Tidskriftsartikel (refereegranskat)abstract
- Cross-reactive CD4+ T cells that recognize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are more commonly detected in the peripheral blood of unexposed individuals compared with SARS-CoV-2–reactive CD8+ T cells. However, large numbers of memory CD8+ T cells reside in tissues, feasibly harboring localized SARS-CoV-2–specific immune responses. To test this idea, we performed a comprehensive functional and phenotypic analysis of virus-specific T cells in tonsils, a major lymphoid tissue site in the upper respiratory tract, and matched peripheral blood samples obtained from children and adults before the emergence of COVID-19 (coronavirus disease 2019). We found that SARS-CoV-2–specific memory CD4+ T cells could be found at similar frequencies in the tonsils and peripheral blood in unexposed individuals, whereas functional SARS-CoV-2–specific memory CD8+ T cells were almost only detectable in the tonsils. Tonsillar SARS-CoV-2–specific memory CD8+ T cells displayed a follicular homing and tissue-resident memory phenotype, similar to tonsillar Epstein-Barr virus–specific memory CD8+ T cells, but were functionally less potent than other virus-specific memory CD8+ T cell responses. The presence of preexisting tissue-resident memory CD8+ T cells in unexposed individuals could potentially enable rapid sentinel immune responses against SARS-CoV-2.
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| 46. |
- Olsson, Kim, et al.
(författare)
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Uncertainty propagation in FE modelling of a fire resistance test using fractional factorial design based model reduction and deterministic sampling
- 2017
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Ingår i: Fire safety journal. - : Elsevier BV. - 0379-7112 .- 1873-7226. ; 91, s. 517-523
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, fractional factorial design (FFD) and deterministic sampling (DS) are applied to a finite element (FE) model of a fire resistance test of a loaded steel beam, to investigate how uncertainties are propagated through the FE model. The sought quantity was the time when the deflection of the beam exceeded 225. mm. The FFD method was used as a model reduction technique which reduced the number of uncertain parameters from 5 to 3. The DS method was compared to a reference Monte Carlo (MC) method of 1000 simulations from all 5 uncertain parameters, which was the minimum number of simulations in order for the statistical moments to converge. The combined FFD and DS method successfully computed the propagation of the mean and standard deviation in the model, compared to the MC method. Given the uncertainties in the FE model, the fractional factorial design reduced the number of simulations required in the DS method by 82%. The combined method of FFD and DS reduced the number of required simulations by 96% compared to the MC method. The DS method did not capture the tails of the probability distribution and is therefore not a suitable candidate for probabilistic evaluation of the time of failure at the edges of the domain of possible failure times. Future research could very well be on improving the tails in DS. However, the DS method provides a conservative 95% coverage interval of 6. min for the time to failure of the steel beam.
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| 47. |
- Petersen, L., et al.
(författare)
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Creating comparable public tolerance and technical performance measures for critical infrastructure resilience evaluation
- 2018
-
Ingår i: Safety and Reliability - Safe Societies in a Changing World - Proceedings of the 28th International European Safety and Reliability Conference, ESREL 2018. - 9780815386827 ; , s. 1231-1240
-
Konferensbidrag (refereegranskat)abstract
- No consensus currently exists on how to measure and evaluate Critical Infrastructure (CI) resilience. Attempting to use the public’s declared coping capacity as a target for CI resilience, this paper explores how to develop relevant resilience performance measurements that enable comparison to the tolerance levels of the general public. To do so, one must first establish the normal performance of the system and the applicable performance measures. Then, a survey is used to convert public perception into these measures as to enable comparison with the technical resilience performance. The CI resilience will be presented through a family of so-called resilience triangles which will illustrate the evolution of the performance, before, during and after a crisis event. A case study of the Municipal Water Network of Barreiro, Portugal, is used. The overall performance is preferably described with the categories quality, quantity and delivery. In quantifying the performance the importance of what is being assessed, to what hazard and for which end-user became evident.
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| 48. |
- Petersen, Laura, et al.
(författare)
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Resilience for whom? : The general public's tolerance levels as CI resilience criteria
- 2020
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Ingår i: International Journal of Critical Infrastructure Protection. - : Elsevier B.V.. - 1874-5482 .- 2212-2087. ; 28
-
Tidskriftsartikel (refereegranskat)abstract
- While maintaining a minimum level of service and rapidly restoring services to normal are key components of critical infrastructure (CI) resilience, who should and how to define these parameters remains under debate. Rarely solicited in the debate, yet integral actors in CI resilience, is the general public. In response to this, this paper presents a questionnaire-based methodology for determining public tolerance levels for service reduction and recovery rapidity. This paper explores this under-researched area using a case-study of the Barreiro Municipal Water Network. It draws on key themes that emerged from the literature as well as interviews with the CI operators in order to develop a tolerance questionnaire, implements said questionnaire (N = 1005), and analysizes the results. Results demonstrate that the methodology works for collecting tolerance levels, that when taking into account vulnerable groups, public tolerance levels appear higher than CI operator capability and that communication expectations are high.
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| 49. |
- Pingel, Ronnie, 1978-
(författare)
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Some Aspects of Propensity Score-based Estimators for Causal Inference
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis consists of four papers that are related to commonly used propensity score-based estimators for average causal effects.The first paper starts with the observation that researchers often have access to data containing lots of covariates that are correlated. We therefore study the effect of correlation on the asymptotic variance of an inverse probability weighting and a matching estimator. Under the assumptions of normally distributed covariates, constant causal effect, and potential outcomes and a logit that are linear in the parameters we show that the correlation influences the asymptotic efficiency of the estimators differently, both with regard to direction and magnitude. Further, the strength of the confounding towards the outcome and the treatment plays an important role.The second paper extends the first paper in that the estimators are studied under the more realistic setting of using the estimated propensity score. We also relax several assumptions made in the first paper, and include the doubly robust estimator. Again, the results show that the correlation may increase or decrease the variances of the estimators, but we also observe that several aspects influence how correlation affects the variance of the estimators, such as the choice of estimator, the strength of the confounding towards the outcome and the treatment, and whether constant or non-constant causal effect is present.The third paper concerns estimation of the asymptotic variance of a propensity score matching estimator. Simulations show that large gains can be made for the mean squared error by properly selecting smoothing parameters of the variance estimator and that a residual-based local linear estimator may be a more efficient estimator for the asymptotic variance. The specification of the variance estimator is shown to be crucial when evaluating the effect of right heart catheterisation, i.e. we show either a negative effect on survival or no significant effect depending on the choice of smoothing parameters. In the fourth paper, we provide an analytic expression for the covariance matrix of logistic regression with normally distributed regressors. This paper is related to the other papers in that logistic regression is commonly used to estimate the propensity score.
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| 50. |
- Pisek, Jan, et al.
(författare)
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Retrieval and validation of forest background reflectivity from daily Moderate Resolution Imaging Spectroradiometer (MODIS) bidirectional reflectance distribution function (BRDF) data across European forests
- 2021
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Ingår i: Biogeosciences. - : Copernicus GmbH. - 1726-4170 .- 1726-4189. ; 18:2, s. 621-635
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Tidskriftsartikel (refereegranskat)abstract
- Information about forest background reflectance is needed for accurate biophysical parameter retrieval from forest canopies (overstory) with remote sensing. Separating under- and overstory signals would enable more accurate modeling of forest carbon and energy fluxes. We retrieved values of the normalized difference vegetation index (NDVI) of the forest understory with the multi-angular Moderate Resolution Imaging Spectroradiometer (MODIS) bidirectional reflectance distribution function (BRDF)/albedo data (gridded 500 m daily Collection 6 product), using a method originally developed for boreal forests. The forest floor background reflectance estimates from the MODIS data were compared with in situ understory reflectance measurements carried out at an extensive set of forest ecosystem experimental sites across Europe. The reflectance estimates from MODIS data were, hence, tested across diverse forest conditions and phenological phases during the growing season to examine their applicability for ecosystems other than boreal forests. Here we report that the method can deliver good retrievals, especially over different forest types with open canopies (low foliage cover). The performance of the method was found to be limited over forests with closed canopies (high foliage cover), where the signal from understory becomes too attenuated. The spatial heterogeneity of individual field sites and the limitations and documented quality of the MODIS BRDF product are shown to be important for the correct assessment and validation of the retrievals obtained with remote sensing.
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