| 1. |
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| 2. |
- Klionsky, Daniel J., et al.
(författare)
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Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
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Ingår i: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
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Forskningsöversikt (refereegranskat)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
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| 3. |
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- 2019
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Tidskriftsartikel (refereegranskat)
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| 4. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 5. |
- Ruilope, LM, et al.
(författare)
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Design and Baseline Characteristics of the Finerenone in Reducing Cardiovascular Mortality and Morbidity in Diabetic Kidney Disease Trial
- 2019
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Ingår i: American journal of nephrology. - : S. Karger AG. - 1421-9670 .- 0250-8095. ; 50:5, s. 345-356
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Tidskriftsartikel (refereegranskat)abstract
- <b><i>Background:</i></b> Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. <b><i>Patients and</i></b> <b><i>Methods:</i></b> The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate ≥25 mL/min/1.73 m<sup>2</sup> and albuminuria (urinary albumin-to-creatinine ratio ≥30 to ≤5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level α = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. <b><i>Conclusions:</i></b> FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049.
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| 6. |
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| 7. |
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| 8. |
- Bentham, James, et al.
(författare)
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A century of trends in adult human height
- 2016
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Ingår i: eLIFE. - 2050-084X. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- Being taller is associated with enhanced longevity, and higher education and earnings. We reanalysed 1472 population-based studies, with measurement of height on more than 18.6 million participants to estimate mean height for people born between 1896 and 1996 in 200 countries. The largest gain in adult height over the past century has occurred in South Korean women and Iranian men, who became 20.2 cm (95% credible interval 17.522.7) and 16.5 cm (13.319.7) taller, respectively. In contrast, there was little change in adult height in some sub-Saharan African countries and in South Asia over the century of analysis. The tallest people over these 100 years are men born in the Netherlands in the last quarter of 20th century, whose average heights surpassed 182.5 cm, and the shortest were women born in Guatemala in 1896 (140.3 cm; 135.8144.8). The height differential between the tallest and shortest populations was 19-20 cm a century ago, and has remained the same for women and increased for men a century later despite substantial changes in the ranking of countries.
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| 9. |
- Bentham, James, et al.
(författare)
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A century of trends in adult human height
- 2016
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Ingår i: eLIFE. - : eLife Sciences Publications Ltd. - 2050-084X. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- Being taller is associated with enhanced longevity, and higher education and earnings. We reanalysed 1472 population-based studies, with measurement of height on more than 18.6 million participants to estimate mean height for people born between 1896 and 1996 in 200 countries. The largest gain in adult height over the past century has occurred in South Korean women and Iranian men, who became 20.2 cm (95% credible interval 17.5–22.7) and 16.5 cm (13.3– 19.7) taller, respectively. In contrast, there was little change in adult height in some sub-Saharan African countries and in South Asia over the century of analysis. The tallest people over these 100 years are men born in the Netherlands in the last quarter of 20th century, whose average heights surpassed 182.5 cm, and the shortest were women born in Guatemala in 1896 (140.3 cm; 135.8– 144.8). The height differential between the tallest and shortest populations was 19-20 cm a century ago, and has remained the same for women and increased for men a century later despite substantial changes in the ranking of countries.
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| 10. |
- Danaei, Goodarz, et al.
(författare)
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Effects of diabetes definition on global surveillance of diabetes prevalence and diagnosis: a pooled analysis of 96 population-based studies with 331288 participants
- 2015
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Ingår i: The Lancet Diabetes & Endocrinology. - 2213-8595 .- 2213-8587. ; 3:8, s. 624-637
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Tidskriftsartikel (refereegranskat)abstract
- Background Diabetes has been defined on the basis of different biomarkers, including fasting plasma glucose (FPG), 2-h plasma glucose in an oral glucose tolerance test (2hOGTT), and HbA(1c). We assessed the effect of different diagnostic definitions on both the population prevalence of diabetes and the classification of previously undiagnosed individuals as having diabetes versus not having diabetes in a pooled analysis of data from population-based health examination surveys in different regions. Methods We used data from 96 population-based health examination surveys that had measured at least two of the biomarkers used for defining diabetes. Diabetes was defined using HbA(1c) (HbA(1c) >= 6 . 5% or history of diabetes diagnosis or using insulin or oral hypoglycaemic drugs) compared with either FPG only or FPG-or-2hOGTT definitions (FPG >= 7 . 0 mmol/L or 2hOGTT >= 11 . 1 mmol/L or history of diabetes or using insulin or oral hypoglycaemic drugs). We calculated diabetes prevalence, taking into account complex survey design and survey sample weights. We compared the prevalences of diabetes using different definitions graphically and by regression analyses. We calculated sensitivity and specificity of diabetes diagnosis based on HbA1c compared with diagnosis based on glucose among previously undiagnosed individuals (ie, excluding those with history of diabetes or using insulin or oral hypoglycaemic drugs). We calculated sensitivity and specificity in each survey, and then pooled results using a random-effects model. We assessed the sources of heterogeneity of sensitivity by meta-regressions for study characteristics selected a priori. Findings Population prevalence of diabetes based on FPG- or-2hOGTT was correlated with prevalence based on FPG alone (r= 0 . 98), but was higher by 2-6 percentage points at different prevalence levels. Prevalence based on HbA(1c) was lower than prevalence based on FPG in 42 . 8% of age-sex-survey groups and higher in another 41 . 6%; in the other 15 . 6%, the two definitions provided similar prevalence estimates. The variation across studies in the relation between glucose-based and HbA(1c)-based prevalences was partly related to participants' age, followed by natural logarithm of per person gross domestic product, the year of survey, mean BMI, and whether the survey population was national, subnational, or from specific communities. Diabetes defined as HbA(1c) 6 . 5% or more had a pooled sensitivity of 52 . 8% (95% CI 51 . 3-54 . 3%) and a pooled specificity of 99 . 74% (99 . 71-99 . 78%) compared with FPG 7 . 0 mmol/L or more for diagnosing previously undiagnosed participants; sensitivity compared with diabetes defined based on FPG-or-2hOGTT was 30 . 5% (28 . 7-32 . 3%). None of the preselected study-level characteristics explained the heterogeneity in the sensitivity of HbA(1c) versus FPG. Interpretation Different biomarkers and definitions for diabetes can provide different estimates of population prevalence of diabetes, and differentially identify people without previous diagnosis as having diabetes. Using an HbA(1c)-based definition alone in health surveys will not identify a substantial proportion of previously undiagnosed people who would be considered as having diabetes using a glucose-based test.
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| 11. |
- Darakchieva, Vanya, et al.
(författare)
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Free electron behavior in InN : On the role of dislocations and surface electron accumulation
- 2009
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 94:2, s. 022109-
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Tidskriftsartikel (refereegranskat)abstract
- The free electron behavior in InN is studied on the basis of decoupled bulk and surface accumulation electron densities in InN films measured by contactless optical Hall effect. It is shown that the variation in the bulk electron density with film thickness does not follow the models of free electrons generated by dislocation-associated nitrogen vacancies. This finding, further supported by transmission electron microscopy results, indicates the existence of a different thickness-dependent doping mechanism. Furthermore, we observe a noticeable dependence of the surface electron density on the bulk density, which can be exploited for tuning the surface charge in future InN based devices.
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| 12. |
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| 13. |
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| 14. |
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| 15. |
- Flannick, Jason, et al.
(författare)
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Data Descriptor : Sequence data and association statistics from 12,940 type 2 diabetes cases and controls
- 2017
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Ingår i: Scientific Data. - : Springer Science and Business Media LLC. - 2052-4463. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- To investigate the genetic basis of type 2 diabetes (T2D) to high resolution, the GoT2D and T2D-GENES consortia catalogued variation from whole-genome sequencing of 2,657 European individuals and exome sequencing of 12,940 individuals of multiple ancestries. Over 27M SNPs, indels, and structural variants were identified, including 99% of low-frequency (minor allele frequency [MAF] 0.1-5%) non-coding variants in the whole-genome sequenced individuals and 99.7% of low-frequency coding variants in the whole-exome sequenced individuals. Each variant was tested for association with T2D in the sequenced individuals, and, to increase power, most were tested in larger numbers of individuals (> 80% of low-frequency coding variants in similar to ~82 K Europeans via the exome chip, and similar to ~90% of low-frequency non-coding variants in similar to ~44 K Europeans via genotype imputation). The variants, genotypes, and association statistics from these analyses provide the largest reference to date of human genetic information relevant to T2D, for use in activities such as T2D-focused genotype imputation, functional characterization of variants or genes, and other novel analyses to detect associations between sequence variation and T2D.
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| 16. |
- Fuchsberger, Christian, et al.
(författare)
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The genetic architecture of type 2 diabetes
- 2016
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 536:7614, s. 41-47
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Tidskriftsartikel (refereegranskat)abstract
- The genetic architecture of common traits, including the number, frequency, and effect sizes of inherited variants that contribute to individual risk, has been long debated. Genome-wide association studies have identified scores of common variants associated with type 2 diabetes, but in aggregate, these explain only a fraction of the heritability of this disease. Here, to test the hypothesis that lower-frequency variants explain much of the remainder, the GoT2D and T2D-GENES consortia performed whole-genome sequencing in 2,657 European individuals with and without diabetes, and exome sequencing in 12,940 individuals from five ancestry groups. To increase statistical power, we expanded the sample size via genotyping and imputation in a further 111,548 subjects. Variants associated with type 2 diabetes after sequencing were overwhelmingly common and most fell within regions previously identified by genome-wide association studies. Comprehensive enumeration of sequence variation is necessary to identify functional alleles that provide important clues to disease pathophysiology, but large-scale sequencing does not support the idea that lower-frequency variants have a major role in predisposition to type 2 diabetes.
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| 17. |
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| 18. |
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| 19. |
- Guo, Hui-Hui, et al.
(författare)
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Alleviation of allergic asthma by rosmarinic acid via gut-lung axis
- 2024
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Ingår i: Phytomedicine. - : Elsevier. - 0944-7113 .- 1618-095X. ; 126
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Tidskriftsartikel (refereegranskat)abstract
- Background: Asthma affects 3% of the global population, leading to over 0.25 million deaths. Due to its complexity, asthma is difficult to cure or prevent, and current therapies have limitations. This has led to a growing demand for alternative asthma treatments. We found rosmarinic acid (RosA) as a potential new drug candidate from natural medicine. However, RosA has poor bioavailability and remains mainly in the gastrointestinal tract after oral administration, suggesting the involvement of gut microbiota in its bioactivity. Purpose: To investigate the mechanism of RosA in alleviating allergic asthma by gut-lung axis. Methods: We used 16S rRNA gene sequencing and metabolites analysis to investigate RosA's modulation of gut microbiota. Techniques of molecular biology and metabolomics were employed to study the pharmacological mechanism of RosA. Cohousing was used to confirm the involvement of gut microbiota in RosA-induced improvement of allergic asthma. Results: RosA decreased cholate levels from spore-forming bacteria, leading to reduced 5-hydroxytryptamine (5HT) synthesis, bronchoconstriction, vasodilation, and inflammatory cell infiltration. It also increased short-chain fatty acids (SCFAs) levels, facilitating the expression of intestinal tight junction proteins to promote intestinal integrity. SCFAs upregulated intestinal monocarboxylate transporters (MCTs), thereby improving their systemic delivery to reduce Th2/ILC2 mediated inflammatory response and suppress eosinophil influx and mucus production in lung. Additionally, RosA inhibited lipopolysaccharide (LPS) production and translocation, leading to reduced TLR4-NF kappa B mediated pulmonary inflammation and oxidative stress. Conclusions: The anti-asthmatic mechanism of oral RosA is primarily driven by modulation of gut microbiotaderived 5-HT, SCFAs, and LPS, achieving a combined synergistic effect. RosA is a safe, effective, and reliable drug candidate that could potentially replace glucocorticoids for asthma treatment.
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| 20. |
- Huang, Zi-Nan, et al.
(författare)
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Analysis of the stress field in the reactor vessel of the China Initiative Accelerator Driven System during postulated ULOF and UTOP transients
- 2023
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Ingår i: Annals of Nuclear Energy. - : Elsevier BV. - 0306-4549 .- 1873-2100. ; 194
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Tidskriftsartikel (refereegranskat)abstract
- The China Initiative Accelerator Driven System (CiADS) was proposed by China Academy of Science since 2015. The subcritical reactor in CiADS is a liquid Lead Bismuth Eutectic (LBE) cooled fast reactor. When the reactor core is in operation, the LBE coolant will directly contact and corrode the inner surface of reactor vessel. Due to the high temperature, the corrosion will be more severe. If the stress on the reactor vessel exceeds the limit, the plastic deformation will occur, leading to the generation and expansion of defects and cracks, and the safety of the reactor will be affected. Therefore, evaluating the stress field of the reactor vessel under different operating conditions is a very important research project. In this paper, the finite element analysis software ADINA was applied to analyze the reactor vessel in CiADS, and the ASME Code was used as stress assessment standards. We can preliminarily prove that the stress assessments of the vessel during the postulated Unprotected Loss of Flow (ULOF) accidents satisfy the requirements of ASME Code. The limit reactivity insertion to protect the vessel from plastic deformation is 0.58$ in the postulated Unprotected Transient over Power (UTOP) accidents based on our current results. Therefore, we can preliminarily conclude that the current material selection and structural design of the reactor vessel in CiADS could survive most of the postulated transient accidents considering the stress effect.
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| 21. |
- Jiang, Linhai, et al.
(författare)
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Controlled Synthesis of CeO2/Graphene Nanocomposites with Highly Enhanced Optical and Catalytic Properties
- 2012
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Ingår i: The Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 116:21, s. 11741-11745
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, CeO2 nanocubes with the (200)-terminated surface/graphene sheet composites have been prepared successfully by a simple hydrothermal method. It is found that the CeO2 nanocubes with high crystallinity and specific exposed surface are well dispersed on well-exfoliated graphene surface. The (200)-terminated surface/graphene sheet composites modified electrode showed much higher sensitivity and excellent selectivity in its catalytic performance compared to a CeO2 nanoparticle-modified electrode. The photoluminescence intensity of the CeO2 anchored on graphene is about 30 times higher than that of pristine CeO2 crystals in air. The higher oxygen vacancy concentration in CeO2 is supposed to be an important cause for the higher photoluminescence and better electrochemical catalytic performance observed in the (200)-terminated surface/graphene sheet composites. Such ingenious design of supported well-dispersed catalysts in nanostructured ceria catalysts, synthesized in one step with an exposed high-activity surface, is important for technical applications and theoretical investigations.
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| 22. |
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| 23. |
- Kristan, Matej, et al.
(författare)
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The Ninth Visual Object Tracking VOT2021 Challenge Results
- 2021
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Ingår i: 2021 IEEE/CVF INTERNATIONAL CONFERENCE ON COMPUTER VISION WORKSHOPS (ICCVW 2021). - : IEEE COMPUTER SOC. - 9781665401913 ; , s. 2711-2738
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Konferensbidrag (refereegranskat)abstract
- The Visual Object Tracking challenge VOT2021 is the ninth annual tracker benchmarking activity organized by the VOT initiative. Results of 71 trackers are presented; many are state-of-the-art trackers published at major computer vision conferences or in journals in recent years. The VOT2021 challenge was composed of four sub-challenges focusing on different tracking domains: (i) VOT-ST2021 challenge focused on short-term tracking in RGB, (ii) VOT-RT2021 challenge focused on "real-time" short-term tracking in RGB, (iii) VOT-LT2021 focused on long-term tracking, namely coping with target disappearance and reappearance and (iv) VOT-RGBD2021 challenge focused on long-term tracking in RGB and depth imagery. The VOT-ST2021 dataset was refreshed, while VOT-RGBD2021 introduces a training dataset and sequestered dataset for winner identification. The source code for most of the trackers, the datasets, the evaluation kit and the results along with the source code for most trackers are publicly available at the challenge website(1).
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| 24. |
- Kristan, Matej, et al.
(författare)
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The Sixth Visual Object Tracking VOT2018 Challenge Results
- 2019
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Ingår i: Computer Vision – ECCV 2018 Workshops. - Cham : Springer Publishing Company. - 9783030110086 - 9783030110093 ; , s. 3-53
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Konferensbidrag (refereegranskat)abstract
- The Visual Object Tracking challenge VOT2018 is the sixth annual tracker benchmarking activity organized by the VOT initiative. Results of over eighty trackers are presented; many are state-of-the-art trackers published at major computer vision conferences or in journals in the recent years. The evaluation included the standard VOT and other popular methodologies for short-term tracking analysis and a “real-time” experiment simulating a situation where a tracker processes images as if provided by a continuously running sensor. A long-term tracking subchallenge has been introduced to the set of standard VOT sub-challenges. The new subchallenge focuses on long-term tracking properties, namely coping with target disappearance and reappearance. A new dataset has been compiled and a performance evaluation methodology that focuses on long-term tracking capabilities has been adopted. The VOT toolkit has been updated to support both standard short-term and the new long-term tracking subchallenges. Performance of the tested trackers typically by far exceeds standard baselines. The source code for most of the trackers is publicly available from the VOT page. The dataset, the evaluation kit and the results are publicly available at the challenge website (http://votchallenge.net).
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| 25. |
- Kristanl, Matej, et al.
(författare)
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The Seventh Visual Object Tracking VOT2019 Challenge Results
- 2019
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Ingår i: 2019 IEEE/CVF INTERNATIONAL CONFERENCE ON COMPUTER VISION WORKSHOPS (ICCVW). - : IEEE COMPUTER SOC. - 9781728150239 ; , s. 2206-2241
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Konferensbidrag (refereegranskat)abstract
- The Visual Object Tracking challenge VOT2019 is the seventh annual tracker benchmarking activity organized by the VOT initiative. Results of 81 trackers are presented; many are state-of-the-art trackers published at major computer vision conferences or in journals in the recent years. The evaluation included the standard VOT and other popular methodologies for short-term tracking analysis as well as the standard VOT methodology for long-term tracking analysis. The VOT2019 challenge was composed of five challenges focusing on different tracking domains: (i) VOT-ST2019 challenge focused on short-term tracking in RGB, (ii) VOT-RT2019 challenge focused on "real-time" short-term tracking in RGB, (iii) VOT-LT2019 focused on long-term tracking namely coping with target disappearance and reappearance. Two new challenges have been introduced: (iv) VOT-RGBT2019 challenge focused on short-term tracking in RGB and thermal imagery and (v) VOT-RGBD2019 challenge focused on long-term tracking in RGB and depth imagery. The VOT-ST2019, VOT-RT2019 and VOT-LT2019 datasets were refreshed while new datasets were introduced for VOT-RGBT2019 and VOT-RGBD2019. The VOT toolkit has been updated to support both standard short-term, long-term tracking and tracking with multi-channel imagery. Performance of the tested trackers typically by far exceeds standard baselines. The source code for most of the trackers is publicly available from the VOT page. The dataset, the evaluation kit and the results are publicly available at the challenge website(1).
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| 26. |
- Li, Lu, 1964, et al.
(författare)
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The Importance of GLUT3 for De Novo Lipogenesis in Hypoxia-Induced Lipid Loading of Human Macrophages
- 2012
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Ingår i: Plos One. - : Public Library of Science (PLoS). - 1932-6203. ; 7:8
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Tidskriftsartikel (refereegranskat)abstract
- Atherosclerotic lesions are characterized by lipid-loaded macrophages (foam cells) and hypoxic regions. Although it is well established that foam cells are produced by uptake of cholesterol from oxidized LDL, we previously showed that hypoxia also promotes foam cell formation even in the absence of exogenous lipids. The hypoxia-induced lipid accumulation results from increased triglyceride biosynthesis but the exact mechanism is unknown. Our aim was to investigate the importance of glucose in promoting hypoxia-induced de novo lipid synthesis in human macrophages. In the absence of exogenous lipids, extracellular glucose promoted the accumulation of Oil Red O-stained lipid droplets in human monocyte-derived macrophages in a concentration-dependent manner. Lipid droplet accumulation was higher in macrophages exposed to hypoxia at all assessed concentrations of glucose. Importantly, triglyceride synthesis from glucose was increased in hypoxic macrophages. GLUT3 was highly expressed in macrophage-rich and hypoxic regions of human carotid atherosclerotic plaques and in macrophages isolated from these plaques. In human monocyte-derived macrophages, hypoxia increased expression of both GLUT3 mRNA and protein, and knockdown of GLUT3 with siRNA significantly reduced both glucose uptake and lipid droplet accumulation. In conclusion, we have shown that hypoxia-induced increases in glucose uptake through GLUT3 are important for lipid synthesis in macrophages, and may contribute to foam cell formation in hypoxic regions of atherosclerotic lesions.
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| 27. |
- Li, Youbing, et al.
(författare)
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A-site alloying-guided universal design of noble metal-based MAX phases
- 2024
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Ingår i: Matter. - : Cell Press. - 2590-2393 .- 2590-2385. ; 7:2, s. 523-538
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Tidskriftsartikel (refereegranskat)abstract
- Mn+1AXn (MAX) phases have attracted significant attention due to their structural diversity and potential applications. Designing MAX phases with single-atom-thick A layers featuring 4d/5d-orbital electronic elements is interesting work. Here, we present a comprehensive report on noble metal-based M2(A1-xA′x)C (M = V, Ti, Nb; A = Al, Sn, In, Ga, Ge; A′ = Ru, Rh, Pd, Ir, Pt, Au and combinations thereof; 0 < x ≤ 0.4) phases featuring A sublayers of 4d/5d-orbital electronic elements through an A-site alloying strategy. The chemical composition of MAX phases can be adjusted by selecting different M- and A-site elements, with morphology tailored by distinct C sources. Furthermore, the V2(Sn0.8Pt0.2)C (15.7 wt % Pt) catalyst showed better performance for hydrogen evolution reaction compared to the commercial Pt/C (20 wt % Pt) electrode. This study highlights the prospects of A-site alloying for the design of novel MAX phases with unique properties and promising applications in electrocatalysis and beyond.
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| 28. |
- Palmer, Nicholette D, et al.
(författare)
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A genome-wide association search for type 2 diabetes genes in African Americans.
- 2012
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Ingår i: PloS one. - San Francisco : Public Library of Science (PLoS). - 1932-6203. ; 7:1, s. e29202-
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Tidskriftsartikel (refereegranskat)abstract
- African Americans are disproportionately affected by type 2 diabetes (T2DM) yet few studies have examined T2DM using genome-wide association approaches in this ethnicity. The aim of this study was to identify genes associated with T2DM in the African American population. We performed a Genome Wide Association Study (GWAS) using the Affymetrix 6.0 array in 965 African-American cases with T2DM and end-stage renal disease (T2DM-ESRD) and 1029 population-based controls. The most significant SNPs (n = 550 independent loci) were genotyped in a replication cohort and 122 SNPs (n = 98 independent loci) were further tested through genotyping three additional validation cohorts followed by meta-analysis in all five cohorts totaling 3,132 cases and 3,317 controls. Twelve SNPs had evidence of association in the GWAS (P<0.0071), were directionally consistent in the Replication cohort and were associated with T2DM in subjects without nephropathy (P<0.05). Meta-analysis in all cases and controls revealed a single SNP reaching genome-wide significance (P<2.5×10(-8)). SNP rs7560163 (P = 7.0×10(-9), OR (95% CI) = 0.75 (0.67-0.84)) is located intergenically between RND3 and RBM43. Four additional loci (rs7542900, rs4659485, rs2722769 and rs7107217) were associated with T2DM (P<0.05) and reached more nominal levels of significance (P<2.5×10(-5)) in the overall analysis and may represent novel loci that contribute to T2DM. We have identified novel T2DM-susceptibility variants in the African-American population. Notably, T2DM risk was associated with the major allele and implies an interesting genetic architecture in this population. These results suggest that multiple loci underlie T2DM susceptibility in the African-American population and that these loci are distinct from those identified in other ethnic populations.
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| 29. |
- Scott, Robert A., et al.
(författare)
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An Expanded Genome-Wide Association Study of Type 2 Diabetes in Europeans
- 2017
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 66:11, s. 2888-2902
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Tidskriftsartikel (refereegranskat)abstract
- To characterize type 2 diabetes (T2D)-associated variation across the allele frequency spectrum, we conducted a meta-analysis of genome-wide association data from 26,676 T2D case and 132,532 control subjects of European ancestry after imputation using the 1000 Genomes multiethnic reference panel. Promising association signals were followed up in additional data sets (of 14,545 or 7,397 T2D case and 38,994 or 71,604 control subjects). We identified 13 novel T2D-associated loci (P < 5 x 10(-8)), including variants near the GLP2R, GIP, and HLA-DQA1 genes. Our analysis brought the total number of independent T2D associations to 128 distinct signals at 113 loci. Despite substantially increased sample size and more complete coverage of low-frequency variation, all novel associations were driven by common single nucleotide variants. Credible sets of potentially causal variants were generally larger than those based on imputation with earlier reference panels, consistent with resolution of causal signals to common risk haplotypes. Stratification of T2D-associated loci based on T2D-related quantitative trait associations revealed tissue-specific enrichment of regulatory annotations in pancreatic islet enhancers for loci influencing insulin secretion and in adipocytes, monocytes, and hepatocytes for insulin action-associated loci. These findings highlight the predominant role played by common variants of modest effect and the diversity of biological mechanisms influencing T2D pathophysiology.
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| 30. |
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| 31. |
- Yang, Fangkai, et al.
(författare)
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Diffusion-Based Time Series Data Imputation for Cloud Failure Prediction at Microsoft 365
- 2023
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Ingår i: ESEC/FSE 2023 - Proceedings of the 31st ACM Joint Meeting European Software Engineering Conference and Symposium on the Foundations of Software Engineering. - : Association for Computing Machinery (ACM). ; , s. 2050-2055
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Konferensbidrag (refereegranskat)abstract
- Ensuring reliability in large-scale cloud systems like Microsoft 365 is crucial. Cloud failures, such as disk and node failure, threaten service reliability, causing service interruptions and financial loss. Existing works focus on failure prediction and proactively taking action before failures happen. However, they suffer from poor data quality, like data missing in model training and prediction, which limits performance. In this paper, we focus on enhancing data quality through data imputation by the proposed Diffusion+, a sample-efficient diffusion model, to impute the missing data efficiently conditioned on the observed data. Experiments with industrial datasets and application practice show that our model contributes to improving the performance of downstream failure prediction.
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| 32. |
- Yang, Lu, et al.
(författare)
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Spasmolytic Mechanism of Aqueous Licorice Extract on Oxytocin-Induced Uterine Contraction through Inhibiting the Phosphorylation of Heat Shock Protein 27
- 2017
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Ingår i: Molecules. - : MDPI AG. - 1431-5157 .- 1420-3049. ; 22:9
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Tidskriftsartikel (refereegranskat)abstract
- Licorice derived from the roots and rhizomes of Glycyrrhiza uralensis Fisch. (Fabaceae), is one of the most widely-used traditional herbal medicines in China. It has been reported to possess significant analgesic activity for treating spastic pain. The aim of this study is to investigate the spasmolytic molecular mechanism of licorice on oxytocin-induced uterine contractions and predict the relevant bioactive constituents in the aqueous extract. The aqueous extraction from licorice inhibited the amplitude and frequency of uterine contraction in a concentration-dependent manner. A morphological examination showed that myometrial smooth muscle cells of oxytocin-stimulated group were oval-shaped and arranged irregularly, while those with a single centrally located nucleus of control and licorice-treated groups were fusiform and arranged orderly. The percentage of phosphorylation of HSP27 at Ser-15 residue increased up to 50.33% at 60 min after oxytocin stimulation. Furthermore, this increase was significantly suppressed by licorice treatment at the concentration of 0.2 and 0.4 mg/mL. Colocalization between HSP27 and alpha-SMA was observed in the myometrial tissues, especially along the actin bundles in the oxytocin-stimulated group. On the contrary, the colocalization was no longer shown after treatment with licorice. Additionally, employing ChemGPS-NP provided support for a preliminary assignment of liquiritigenin and isoliquiritigenin as protein kinase C (PKC) inhibitors in addition to liquiritigenin, isoliquiritigenin, liquiritin and isoliquiritin as MAPK-activated protein kinase 2 (MK2) inhibitors. These assigned compounds were docked with corresponding crystal structures of respective proteins with negative and low binding energy, which indicated a high affinity and tight binding capacity for the active site of the kinases. These results suggest that licorice exerts its spasmolytic effect through inhibiting the phosphorylation of HSP27 to alter the interaction between HSP27 and actin. Furthermore, our results provide support for the prediction that potential bioactive constituents from aqueous licorice extract inhibit the relevant up-stream kinases that phosphorylate HSP27.
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| 33. |
- Zhou, Bin, et al.
(författare)
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Worldwide trends in diabetes since 1980: A pooled analysis of 751 population-based studies with 4.4 million participants
- 2016
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Ingår i: The Lancet. - : Elsevier B.V.. - 0140-6736 .- 1474-547X. ; 387:10027, s. 1513-1530
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Tidskriftsartikel (refereegranskat)abstract
- Background: One of the global targets for non-communicable diseases is to halt, by 2025, the rise in the age standardised adult prevalence of diabetes at its 2010 levels. We aimed to estimate worldwide trends in diabetes, how likely it is for countries to achieve the global target, and how changes in prevalence, together with population growth and ageing, are aff ecting the number of adults with diabetes.Methods: We pooled data from population-based studies that had collected data on diabetes through measurement of its biomarkers. We used a Bayesian hierarchical model to estimate trends in diabetes prevalence-defined as fasting plasma glucose of 7.0 mmol/L or higher, or history of diagnosis with diabetes, or use of insulin or oral hypoglycaemic drugs-in 200 countries and territories in 21 regions, by sex and from 1980 to 2014. We also calculated the posterior probability of meeting the global diabetes target if post-2000 trends continue.Findings: We used data from 751 studies including 4372000 adults from 146 of the 200 countries we make estimates for. Global age-standardised diabetes prevalence increased from 4.3% (95% credible interval 2.4-17.0) in 1980 to 9.0% (7.2-11.1) in 2014 in men, and from 5.0% (2.9-7.9) to 7.9% (6.4-9.7) in women. The number of adults with diabetes in the world increased from 108 million in 1980 to 422 million in 2014 (28.5% due to the rise in prevalence, 39.7% due to population growth and ageing, and 31.8% due to interaction of these two factors). Age-standardised adult diabetes prevalence in 2014 was lowest in northwestern Europe, and highest in Polynesia and Micronesia, at nearly 25%, followed by Melanesia and the Middle East and north Africa. Between 1980 and 2014 there was little change in age-standardised diabetes prevalence in adult women in continental western Europe, although crude prevalence rose because of ageing of the population. By contrast, age-standardised adult prevalence rose by 15 percentage points in men and women in Polynesia and Micronesia. In 2014, American Samoa had the highest national prevalence of diabetes (>30% in both sexes), with age-standardised adult prevalence also higher than 25% in some other islands in Polynesia and Micronesia. If post-2000 trends continue, the probability of meeting the global target of halting the rise in the prevalence of diabetes by 2025 at the 2010 level worldwide is lower than 1% for men and is 1% for women. Only nine countries for men and 29 countries for women, mostly in western Europe, have a 50% or higher probability of meeting the global target.Interpretation: Since 1980, age-standardised diabetes prevalence in adults has increased, or at best remained unchanged, in every country. Together with population growth and ageing, this rise has led to a near quadrupling of the number of adults with diabetes worldwide. The burden of diabetes, both in terms of prevalence and number of adults aff ected, has increased faster in low-income and middle-income countries than in high-income countries.
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| 34. |
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| 35. |
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| 36. |
- Abelev, Betty, et al.
(författare)
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Long-range angular correlations on the near and away side in p-Pb collisions at root S-NN=5.02 TeV
- 2013
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Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 719:1-3, s. 29-41
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Tidskriftsartikel (refereegranskat)abstract
- Angular correlations between charged trigger and associated particles are measured by the ALICE detector in p-Pb collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV for transverse momentum ranges within 0.5 < P-T,P-assoc < P-T,P-trig < 4 GeV/c. The correlations are measured over two units of pseudorapidity and full azimuthal angle in different intervals of event multiplicity, and expressed as associated yield per trigger particle. Two long-range ridge-like structures, one on the near side and one on the away side, are observed when the per-trigger yield obtained in low-multiplicity events is subtracted from the one in high-multiplicity events. The excess on the near-side is qualitatively similar to that recently reported by the CMS Collaboration, while the excess on the away-side is reported for the first time. The two-ridge structure projected onto azimuthal angle is quantified with the second and third Fourier coefficients as well as by near-side and away-side yields and widths. The yields on the near side and on the away side are equal within the uncertainties for all studied event multiplicity and p(T) bins, and the widths show no significant evolution with event multiplicity or p(T). These findings suggest that the near-side ridge is accompanied by an essentially identical away-side ridge. (c) 2013 CERN. Published by Elsevier B.V. All rights reserved.
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| 37. |
- Abelev, Betty, et al.
(författare)
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Measurement of prompt J/psi and beauty hadron production cross sections at mid-rapidity in pp collisions at root s=7 TeV
- 2012
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; :11
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Tidskriftsartikel (refereegranskat)abstract
- The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at root s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L-int = 5.6 nb(-1). The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum p(t) > 1,3 GeV/c and rapidity vertical bar y vertical bar < 0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the psi(2S) and chi(c) resonances, is sigma(prompt J/psi) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 8.3 +/- 0.8(stat.) +/- 1.1 (syst.)(-1.4)(+1.5) (syst. pol.) mu b. The cross section for the production of b-hadrons decaying to J/psi with p(t) > 1.3 GeV/c and vertical bar y vertical bar < 0.9 is a sigma(J/psi <- hB) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 1.46 +/- 0.38 (stat.)(-0.32)(+0.26) (syst.) mu b. The results are compared to QCD model predictions. The shape of the p(t) and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the b (b) over bar pair total cross section and d sigma/dy at mid-rapidity.
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| 38. |
- Álvarez-Muñiz, Jaime, et al.
(författare)
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The Giant Radio Array for Neutrino Detection (GRAND) : Science and design
- 2020
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Ingår i: Science China Physics, Mechanics & Astronomy. - : Springer Science and Business Media LLC. - 1674-7348 .- 1869-1927. ; 63:1
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Forskningsöversikt (refereegranskat)abstract
- The Giant Radio Array for Neutrino Detection (GRAND) is a planned large-scale observatory of ultra-high-energy (UHE) cosmic particles, with energies exceeding 108 GeV. Its goal is to solve the long-standing mystery of the origin of UHE cosmic rays. To do this, GRAND will detect an unprecedented number of UHE cosmic rays and search for the undiscovered UHE neutrinos and gamma rays associated to them with unmatched sensitivity. GRAND will use large arrays of antennas to detect the radio emission coming from extensive air showers initiated by UHE particles in the atmosphere. Its design is modular: 20 separate, independent sub-arrays, each of 10000 radio antennas deployed over 10000 km(2). A staged construction plan will validate key detection techniques while achieving important science goals early. Here we present the science goals, detection strategy, preliminary design, performance goals, and construction plans for GRAND.
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| 39. |
- Arnaudov, B, et al.
(författare)
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Energy position of near-band-edge emission spectra of InN epitaxial layers with different doping levels
- 2004
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 69:11
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Tidskriftsartikel (refereegranskat)abstract
- We studied the shape and energy position of near-band-edge photoluminescence spectra of InN epitaxial layers with different doping levels. We found that the experimental spectra of InN layers with moderate doping level can be nicely interpreted in the frames of the "free-to-bound" recombination model in degenerate semiconductors. For carrier concentrations above n>5x10(18) cm(-3) the emission spectra can also be modeled satisfactorily, but a contribution due to a pushing up of nonequilibrium holes over the thermal delocalization level in the valence band tails should be considered in the model. The emission spectra of samples with low doping level were instead explained as a recombination from the bottom of the conduction band to a shallow acceptor assuming the same value of the acceptor binding energy estimated from the spectra of highly doped samples. Analyzing the shape and energy position of the free-electron recombination spectra we determined the carrier concentrations responsible for the emissions and found that the fundamental band gap energy of InN is E-g=692+/-2 meV for an effective mass at the conduction-band minimum m(n0)=0.042m(0).
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| 40. |
- Arnaudov, B., et al.
(författare)
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Free-to-bound radiative recombination in highly conducting InN epitaxial layers
- 2004
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Ingår i: Superlattices and Microstructures. - : Elsevier BV. - 0749-6036 .- 1096-3677. ; 36:4-6, s. 563-571
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Tidskriftsartikel (refereegranskat)abstract
- We present a theoretical simulation of near-band-edge emission spectra of highly conducting n-InN assuming the model of 'free-to-bound' radiative recombination (FBRR) of degenerate electrons from the conduction band with nonequilibrium holes located in the valence band tails. We also study experimental photoluminescence (PL) spectra of highly conducting InN epitaxial layers grown by MBE and MOVPE with electron concentrations in the range (7.7 × 1017-6 × 1018) cm-3 and find that the energy positions and shape of the spectra depend on the impurity concentration. By modeling the experimental PL spectra of the InN layers we show that spectra can be nicely interpreted in the framework of the FBRR model with specific peculiarities for different doping levels. Analyzing simultaneously the shape and energy position of the InN emission spectra we determine the fundamental bandgap energy of InN to vary between Eg = 692 meV for effective mass mn0 = 0.042m0 and Eg =710 meV for mn0 = 0.1m0. © 2004 Elsevier Ltd. All rights reserved.
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| 41. |
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| 42. |
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| 43. |
- Bi, Zhaoxia, et al.
(författare)
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InGaN Platelets : Synthesis and Applications toward Green and Red Light-Emitting Diodes
- 2019
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Ingår i: Nano Letters. - : American Chemical Society. - 1530-6984 .- 1530-6992. ; 19:5, s. 2832-2839
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Tidskriftsartikel (refereegranskat)abstract
- In this work, we present a method to synthesize arrays of hexagonal InGaN submicrometer platelets with a top c-plane area having an extension of a few hundred nanometers by selective area metal-organic vapor-phase epitaxy. The InGaN platelets were made by in situ annealing of InGaN pyramids, whereby InGaN from the pyramid apex was thermally etched away, leaving a c-plane surface, while the inclined {101Ì1} planes of the pyramids were intact. The as-formed c-planes, which are rough with islands of a few tens of nanometers, can be flattened with InGaN regrowth, showing single bilayer steps and high-quality optical properties (full width at half-maximum of photoluminescence at room temperature: 107 meV for In 0.09 Ga 0.91 N and 151 meV for In 0.18 Ga 0.82 N). Such platelets offer surfaces having relaxed lattice constants, thus enabling shifting the quantum well emission from blue (as when grown on GaN) to green and red. For single InGaN quantum wells grown on the c-plane of such InGaN platelets, a sharp interface between the quantum well and the barriers was observed. The emission energy from the quantum well, grown under the same conditions, was shifted from 2.17 eV on In 0.09 Ga 0.91 N platelets to 1.95 eV on In 0.18 Ga 0.82 N platelets as a result of a thicker quantum well and a reduced indium pulling effect on In 0.18 Ga 0.82 N platelets. On the basis of this method, prototype light-emitting diodes were demonstrated with green emission on In 0.09 Ga 0.91 N platelets and red emission on In 0.18 Ga 0.82 N platelets.
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| 44. |
- Bi, Zhaoxia, et al.
(författare)
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Realization of Ultrahigh Quality InGaN Platelets to be Used as Relaxed Templates for Red Micro-LEDs
- 2020
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Ingår i: ACS Applied Materials and Interfaces. - : NLM (Medline). - 1944-8244 .- 1944-8252. ; 12:15, s. 17845-17851
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Tidskriftsartikel (refereegranskat)abstract
- In this work, arrays of predominantly relaxed InGaN platelets with indium contents of up to 18%, free from dislocations and offering a smooth top c-plane, are presented. The InGaN platelets are grown by metal-organic vapor phase epitaxy on a dome-like InGaN surface formed by chemical mechanical polishing of InGaN pyramids defined by 6 equivalent {101̅1} planes. The dome-like surface is flattened during growth, through the formation of bunched steps, which are terminated when reaching the inclined {101̅1} planes. The continued growth takes place on the flattened top c-plane with single bilayer surface steps initiated at the six corners between the c-plane and the inclined {101̅1} planes, leading to the formation of high-quality InGaN layers. The top c-plane of the as-formed InGaN platelets can be used as a high-quality template for red micro light-emitting diodes.
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| 45. |
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| 46. |
- Bu, Changshen, et al.
(författare)
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Oxy-fuel conversion of sub-bituminous coal particles in fluidized bed and pulverized combustors
- 2017
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Ingår i: Proceedings of the Combustion Institute. - : Elsevier BV. - 1540-7489. ; 36:3, s. 3331-3339
-
Tidskriftsartikel (refereegranskat)abstract
- Oxy-fuel combustion in pulverized coal (PC) and fluidizedbed (FB) boilers is being increasingly investigated due toits potential use for carbon dioxide capture. The combustionconditions in the two types of unit differ significantlybecause of fuel size, furnace temperature, and fluid dynamics. These differences affect the change of combustioncharacteristics from air (O2/N2)to oxy-fuel (O2/CO2) conditions in PC and FB in different ways. In this paper, the oxy-fuel combustion behavior of a single sub-bituminouscoal particle in PC is compared with that in FB conditions.The FB data were measured in our bench-scale FB test rig,whereas the PC data were collected from literature. The FB tests were performed at 1088 K with 0%vol
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| 47. |
- Bu, C. S., et al.
(författare)
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Effect of CO2 on oxy-fuel combustion of coal-char particles in a fluidized bed: Modeling and comparison with the conventional mode of combustion
- 2016
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Ingår i: Applied Energy. - : Elsevier BV. - 1872-9118 .- 0306-2619. ; 177, s. 247-259
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Tidskriftsartikel (refereegranskat)abstract
- A char combustion model is developed to study the effect of CO2 on the combustion of coarse char particles under oxy-fuel conditions in a fluidized bed (FB). It is a transient one-dimensional model, taking into account the heat and mass transfer from the bed to the particle and the heterogeneous combustion and gasification of char. The model shows good ability to predict the char temperature history measured in our previous work for different combinations of O2/CO2 and O2/N2 with various coal types. Simulations are carried out to establish the role of CO2 in oxy-fuel conversion at different O2 levels, particle sizes, and bed temperatures. The model is used to analyze the relative contribution of carbon in the char consumed by CO2 (gasification) and O2 (combustion), as well as the differences of the peak temperatures and the burnout times in O2/CO2 and O2/N2 for char particles in a commercial FB combustor. The results indicate that the conversion of coarse (mm size) char particles in an oxy-FB is controlled by the diffusion of O2 both in the O2/CO2 and O2/N2 case. The burn-out time decreases with the bed temperature also in both cases. The lower O2 diffusion rate in CO2 compared to N2, is the main reason for the longer burnout time and lower peak temperature found using O2/CO2 at bed temperatures of 1073–1173 K. In that temperature window, the contribution of the CO2-char gasification is limited, being notable only at high bed temperature in O2/CO2, e.g. 1223 K. In such high temperature conditions (rarely expected to be found in commercial coal FBC) the predicted burnout time of a lignite char-particle becomes shorter in O2/CO2 than in O2/N2.
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| 48. |
- Bu, C. S., et al.
(författare)
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Oxy-fuel combustion of a single fuel particle in a fluidized bed: Char combustion characteristics, an experimental study
- 2016
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Ingår i: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947. ; 287, s. 649-656
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Tidskriftsartikel (refereegranskat)abstract
- The effect of an oxy-fuel atmosphere on char conversion in a fluidized bed (FB) was examined by comparingmeasurements of single fuel particles exposed to O2/N2 and O2/CO2 atmospheres. The experimentswere carried out in a transparent and electrically heated FB at 1088 K and five O2 inlet concentrations(ranging from 0 up to 40%vol) using four ranks of coal (from anthracite to lignite) and one type of wood,all with 6 mm (spherical) diameter. The evolution of temperature with time of the various fuels at differentgas atmospheres and the microstructure of the char resulting after devolatilization are presented,from which the effect of the oxy-fuel atmosphere (changing CO2 by N2 at different fixed O2 concentrations)on char combustion characteristics is determined and analyzed. Results show that the apparentaverage combustion rate of a fuel particle decreases (and consequently the burnout time increases) whenchanging O2/N2 by O2/CO2. This effect was more significant at high O2 concentrations and most notablefor anthracite. Consistently, the time to reach the peak temperature was longer when shifting from O2/N2to O2/CO2. However, the char specific surface area, pore volume, and average pore diameter of char werenot significantly modified by replacing N2 with CO2.
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| 49. |
- Chen, Q., et al.
(författare)
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Thermodynamic calculation and kinetic simulation related to solidification process
- 2006
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Ingår i: Modeling of Casting, Welding and Advanced Solidification Processes - XI. - 0873396294 - 9780873396295 ; , s. 529-536
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Konferensbidrag (refereegranskat)abstract
- This paper presents a brief review and some new results of the thermodynamic calculation and kinetic simulation related to the micro-modelling of solidification processes by using ThermoCalc and DICTRA. Emphasis is given on a partial-equilibrium approach developed as a modification of the Scheil-Gulliver non-equilibrium approximation to treat effectively the back diffusion of fast diffusing elements in solid phases. We start with a DICTRA simulation and successfully explain why the P peak drifts away from those of Mn and Si in the experimentally observed composition profiles of a carbon steel. Then, for this steel and other 16 carbon and low alloy steels, we perform both non-equilibrium and partial-equilibrium solidification calculations and demonstrate the significant improvement of the partial-equilibrium approach by comparing the freezing range results with those from either DICTRA simulations or experimental observations.
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| 50. |
- Daelman, Bo, et al.
(författare)
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Frailty and cognitive function in middle-aged and older adults with congenital heart disease
- 2024
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Ingår i: Journal of the American College of Cardiology. - : Elsevier. - 0735-1097 .- 1558-3597. ; 83:12, s. 1149-1159
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Tidskriftsartikel (refereegranskat)abstract
- Background: Life expectancy of patients with congenital heart disease (CHD) has increased rapidly, resulting in a growing and aging population. Recent studies have shown that older people with CHD have higher morbidity, health care use, and mortality. To maintain longevity and quality of life, understanding their evolving medical and psychosocial challenges is essential.Objectives: The authors describe the frailty and cognitive profile of middle-aged and older adults with CHD to identify predictor variables and to explore the relationship with hospital admissions and outpatient visits.Methods: Using a cross-sectional, multicentric design, we included 814 patients aged ≥40 years from 11 countries. Frailty phenotype was determined using the Fried method. Cognitive function was assessed by the Montreal Cognitive Assessment.Results: In this sample, 52.3% of patients were assessed as robust, 41.9% as prefrail, and 5.8% as frail; 38.8% had cognitive dysfunction. Multinomial regression showed that frailty was associated with older age, female sex, higher physiologic class, and comorbidities. Counterintuitively, patients with mild heart defects were more likely than those with complex lesions to be prefrail. Patients from middle-income countries displayed more prefrailty than those from higher-income countries. Logistic regression demonstrated that cognitive dysfunction was related to older age, comorbidities, and lower country-level income.Conclusions: Approximately one-half of included patients were (pre-)frail, and more than one-third experienced cognitive impairment. Frailty and cognitive dysfunction were identified in patients with mild CHD, indicating that these concerns extend beyond severe CHD. Assessing frailty and cognition routinely could offer valuable insights into this aging population.
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