| 11. |
- Cheng, Qiaoyun, et al.
(författare)
-
The conversion of nanocellulose into solvent-free nanoscale liquid crystals by attaching long side-arms for multi-responsive optical materials
- 2020
-
Ingår i: Journal of Materials Chemistry C. - : ROYAL SOC CHEMISTRY. - 2050-7526 .- 2050-7534. ; 8:32, s. 11022-11031
-
Tidskriftsartikel (refereegranskat)abstract
- Nanocellulose, with its unique optical and chemical properties, has received increasing attention as feedstock to fabricate sustainable materials. However, achieving a nanocellulose-based solvent-free liquid crystal with good responsiveness still remains a challenge. Herein, for the first time, solvent-free supramolecular liquid crystals were fabricated by attaching long side-arms on the fiber-like nanocellulose derived from tunicate (TCNC) with an average width of 20 nm and 400-3000 nm in length. The side-arms were grafted via surface condensation with a charged organosilane, followed by further functionalization with a counter-ion polyoxyethylene ether. The nanoscale liquid crystals consisted of the stiff TCNC as the core and flexible side-arms as the soft shells, forming the core-shell structure with an average width of 34-36 nm. The resulting solvent-free liquid crystal exhibited transparent and viscous liquid-like fluidity, as well as a bright birefringence between the crossed polarizers at room temperature. In our findings, the stiff core provided crystal-like ordering, whereas the soft shells induced the high mobility of the TCNCs as a result of the increased fractional free volume, as shown by positron annihilation lifetime spectra. The unique flowability enables the possibility of multi-responsiveness to temperature, deformation, and alternating electric fields. In addition, the thermo-responsiveness can be regulated by tailoring the canopy. This work provides a novel strategy for the conversion of solid nanocellulose into a solvent-free nanoscale liquid crystal, which is promising for use as a responsive optical material.
|
|
| 12. |
- Demerath, Ellen W., et al.
(författare)
-
Epigenome-wide association study (EWAS) of BMI, BMI change and waist circumference in African American adults identifies multiple replicated loci
- 2015
-
Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 24:15, s. 4464-4479
-
Tidskriftsartikel (refereegranskat)abstract
- Obesity is an important component of the pathophysiology of chronic diseases. Identifying epigenetic modifications associated with elevated adiposity, including DNA methylation variation, may point to genomic pathways that are dysregulated in numerous conditions. The Illumina 450K Bead Chip array was used to assay DNA methylation in leukocyte DNA obtained from 2097 African American adults in the Atherosclerosis Risk in Communities (ARIC) study. Mixed-effects regression models were used to test the association of methylation beta value with concurrent body mass index (BMI) and waist circumference (WC), and BMI change, adjusting for batch effects and potential confounders. Replication using whole-blood DNA from 2377 White adults in the Framingham Heart Study and CD4+ T cell DNA from 991 Whites in the Genetics of Lipid Lowering Drugs and Diet Network Study was followed by testing using adipose tissue DNA from 648 women in the Multiple Tissue Human Expression Resource cohort. Seventy-six BMI-related probes, 164 WC-related probes and 8 BMI change-related probes passed the threshold for significance in ARIC (P < 1 x 10(-7); Bonferroni), including probes in the recently reported HIF3A, CPT1A and ABCG1 regions. Replication using blood DNA was achieved for 37 BMI probes and 1 additional WC probe. Sixteen of these also replicated in adipose tissue, including 15 novel methylation findings near genes involved in lipid metabolism, immune response/cytokine signaling and other diverse pathways, including LGALS3BP, KDM2B, PBX1 and BBS2, among others. Adiposity traits are associated with DNA methylation at numerous CpG sites that replicate across studies despite variation in tissue type, ethnicity and analytic approaches.
|
|
| 13. |
- Fedorowski, Artur, et al.
(författare)
-
Orthostatic hypotension and novel blood pressure-associated gene variants: Genetics of Postural Hemodynamics (GPH) Consortium.
- 2012
-
Ingår i: European Heart Journal. - : Oxford University Press (OUP). - 1522-9645 .- 0195-668X. ; 33:18, s. 2331-2341
-
Tidskriftsartikel (refereegranskat)abstract
- Aims: Orthostatic hypotension (OH), an independent predictor of mortality and cardiovascular events, strongly correlates with hypertension. Recent genome-wide studies have identified new loci influencing blood pressure (BP) in populations, but their impact on OH remains unknown.Methods and resultsA total of 38 970 men and women of European ancestry from five population-based cohorts were included, of whom 2656 (6.8%) met the diagnostic criteria for OH (systolic/diastolic BP drop ≥20/10 mmHg within 3 min of standing). Thirty-one recently discovered BP-associated single nucleotide polymorphisms (SNPs) were examined using an additive genetic model and the major allele as referent. Relations between OH, orthostatic systolic BP response, and genetic variants were assessed by inverse variance-weighted meta-analysis. We found Bonferroni adjusted (P < 0.0016) significant evidence for association between OH and the EBF1 locus (rs11953630, per-minor-allele odds ratio, 95% confidence interval: 0.90, 0.85-0.96; P = 0.001), and nominal evidence (P < 0.05) for CYP17A1 (rs11191548: 0.85, 0.75-0.95; P = 0.005), and NPR3-C5orf23 (rs1173771: 0.92, 0.87-0.98; P= 0.009) loci. Among subjects not taking BP-lowering drugs, three SNPs within the NPPA/NPPB locus were nominally associated with increased risk of OH (rs17367504: 1.13, 1.02-1.24; P = 0.02, rs198358: 1.10, 1.01-1.20; P = 0.04, and rs5068: 1.22, 1.04-1.43; P = 0.01). Moreover, an ADM variant was nominally associated with continuous orthostatic systolic BP response in the adjusted model (P= 0.04).ConclusionThe overall association between common gene variants in BP loci and OH was generally weak and the direction of effect inconsistent with resting BP findings. These results suggest that OH and resting BP share few genetic components.
|
|
| 14. |
- Hedman, Åsa K., et al.
(författare)
-
Epigenetic Patterns in Blood Associated With Lipid Traits Predict Incident Coronary Heart Disease Events and Are Enriched for Results From Genome-Wide Association Studies
- 2017
-
Ingår i: Circulation. - : LIPPINCOTT WILLIAMS & WILKINS. - 1942-325X .- 1942-3268. ; 10:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background- Genome-wide association studies have identified loci influencing circulating lipid concentrations in humans; further information on novel contributing genes, pathways, and biology may be gained through studies of epigenetic modifications. Methods and Results- To identify epigenetic changes associated with lipid concentrations, we assayed genome-wide DNA methylation at cytosine-guanine dinucleotides (CpGs) in whole blood from 2306 individuals from 2 population-based cohorts, with replication of findings in 2025 additional individuals. We identified 193 CpGs associated with lipid levels in the discovery stage (P < 1.08E-07) and replicated 33 (at Bonferroni-corrected P < 0.05), including 25 novel CpGs not previously associated with lipids. Genes at lipid-associated CpGs were enriched in lipid and amino acid metabolism processes. A differentially methylated locus associated with triglyceridesand high-density lipoprotein cholesterol (HDL- C; cg27243685; P= 8.1E-26 and 9.3E-19) was associated with cis-expression of a reverse cholesterol transporter (ABCG1; P= 7.2E-28) and incident cardiovascular disease events (hazard ratio per SD increment, 1.38; 95% confidence interval, 1.15-1.66; P= 0.0007). We found significant cis-methylation quantitative trait loci at 64% of the 193 CpGs with an enrichment of signals from genome-wide association studies of lipid levels (P-TC = 0.004, PHDL-C = 0.008 and P-triglycerides = 0.00003) and coronary heart disease ( P= 0.0007). For example, genome-wide significant variants associated with low-density lipoprotein cholesterol and coronary heart disease at APOB were cis-methylation quantitative trait loci for a low-density lipoprotein cholesterol-related differentially methylated locus. Conclusions-We report novel associations of DNA methylation with lipid levels, describe epigenetic mechanisms related to previous genome-wide association studies discoveries, and provide evidence implicating epigenetic regulation of reverse cholesterol transport in blood in relation to occurrence of cardiovascular disease events.
|
|
| 15. |
- Hou, Liping, et al.
(författare)
-
Genome-wide association study of 40,000 individuals identifies two novel loci associated with bipolar disorder.
- 2016
-
Ingår i: Human molecular genetics. - : Oxford University Press (OUP). - 1460-2083 .- 0964-6906. ; 25:15, s. 3383-94
-
Tidskriftsartikel (refereegranskat)abstract
- Bipolar disorder (BD) is a genetically complex mental illness characterized by severe oscillations of mood and behavior. Genome-wide association studies (GWAS) have identified several risk loci that together account for a small portion of the heritability. To identify additional risk loci, we performed a two-stage meta-analysis of >9 million genetic variants in 9,784 bipolar disorder patients and 30,471 controls, the largest GWAS of BD to date. In this study, to increase power we used ∼2,000 lithium-treated cases with a long-term diagnosis of BD from the Consortium on Lithium Genetics, excess controls, and analytic methods optimized for markers on the X-chromosome. In addition to four known loci, results revealed genome-wide significant associations at two novel loci: an intergenic region on 9p21.3 (rs12553324, p = 5.87 × 10(-9); odds ratio = 1.12) and markers within ERBB2 (rs2517959, p = 4.53 × 10(-9); odds ratio = 1.13). No significant X-chromosome associations were detected and X-linked markers explained very little BD heritability. The results add to a growing list of common autosomal variants involved in BD and illustrate the power of comparing well-characterized cases to an excess of controls in GWAS.
|
|
| 16. |
- Huan, Tianxiao, et al.
(författare)
-
Genome-wide identification of DNA methylation QTLs in whole blood highlights pathways for cardiovascular disease
- 2019
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- Identifying methylation quantitative trait loci (meQTLs) and integrating them with disease-associated variants from genome-wide association studies (GWAS) may illuminate functional mechanisms underlying genetic variant-disease associations. Here, we perform GWAS of >415 thousand CpG methylation sites in whole blood from 4170 individuals and map 4.7 million cis- and 630 thousand trans-meQTL variants targeting >120 thousand CpGs. Independent replication is performed in 1347 participants from two studies. By linking cis-meQTL variants with GWAS results for cardiovascular disease (CVD) traits, we identify 92 putatively causal CpGs for CVD traits by Mendelian randomization analysis. Further integrating gene expression data reveals evidence of cis CpG-transcript pairs causally linked to CVD. In addition, we identify 22 trans-meQTL hotspots each targeting more than 30 CpGs and find that trans-meQTL hotspots appear to act in cis on expression of nearby transcriptional regulatory genes. Our findings provide a powerful meQTL resource and shed light on DNA methylation involvement in human diseases.
|
|
| 17. |
- Li, Zhiqi, et al.
(författare)
-
Efficient perovskite solar cells enabled by ion-modulated grain boundary passivation with a fill factor exceeding 84%
- 2019
-
Ingår i: Journal of Materials Chemistry A. - : ROYAL SOC CHEMISTRY. - 2050-7488 .- 2050-7496. ; 7:39, s. 22359-22365
-
Tidskriftsartikel (refereegranskat)abstract
- Alkali metal cation modulation toward high-electronic-quality perovskite films requires strict control over trap densities in the devices. By introducing tailor-made potassium cation (K+)-functionalized carbon nanodots (CNDs@K) into the perovskite precursor solution, we succeeded in defect passivation and crystallization control of the perovskite film. X-ray diffraction indicated that the binding effect of carbon dots confined the K+ ions in the grain boundary and prevented excessive cations from occupying interstitial sites, thereby reducing the microstrain of the polycrystalline film. Consequently, the synergistic effect of the tailored crystal size and suppressed grain boundary defects could reduce the charge trap density, facilitate charge generation, and lengthen the carrier lifetime, leading to a boosted efficiency of 21.01% with a high fill factor of 84%. This performance is among the best reported for carbon dot-doped PSCs.
|
|
| 18. |
- Liu, Chunyu, et al.
(författare)
-
Experimental study on effects of ammonia enrichment on the thermoacoustic instability of lean premixed swirling methane flames
- 2024
-
Ingår i: Fuel. - 0016-2361. ; 357
-
Tidskriftsartikel (refereegranskat)abstract
- Ammonia (NH3) has recently emerged as a promising carbon-free energy carrier. Further development and application of NH3 as fuel in the gas turbine industry can significantly reduce the emissions of carbon dioxide (CO2) and contribute to the achievement of a carbon–neutral society. This study experimentally examined the thermoacoustic instability characteristics of a laboratory-scaled lean premixed gas turbine model combustor operated with different NH3 blending ratios with methane (CH4). Experiments conducted under a wide range of inlet velocities and equivalence ratios suggest that NH3 concentration is critical in determining the characteristics of the instability. Specifically, when the NH3 proportion is less than 50 %, the addition of NH3 causes a mode transition of the instability. However, when the content of NH3 is greater than 50 %, it is shown that the instabilities are suppressed, indicating that the addition of a certain amount of NH3 can enhance the stability of CH4 flames. Additional analysis of flame dynamics reveals that the introduction of NH3 causes the lengthening of the flame front and weakens heat release rate fluctuations in the flame root regions. Further Proper Orthogonal Decomposition (POD) analysis of the flow field shows that the instability modes are strongly coupled with periodic vortex motions of the flow dynamics along the shear layers. Finally, the mode shifting phenomena is successfully predicted by low-order thermoacoustic network modeling. It is suggested that the change in convective time delay caused by NH3 addition is responsible for such transitions.
|
|
| 19. |
- Liu, Chunyu, et al.
(författare)
-
Influence of swirl intensity on combustion dynamics and emissions in an ammonia-enriched methane/air combustor
- 2024
-
Ingår i: Physics of Fluids. - 1070-6631. ; 36:3
-
Tidskriftsartikel (refereegranskat)abstract
- Ammonia (NH3) has been widely considered as a promising carbon-free energy and hydrogen carrier for various applications. The large-scale direct utilization of NH3 as fuel in gas turbine engines is currently attracting significant interest, with strong focuses on improving the efficiency and stability of the system and reducing the emissions of pollutants. The present study experimentally examined the impacts of swirl intensity on combustion stability and emissions in an NH3-enriched premixed swirl-stabilized CH4/air combustor under a wide range of equivalence ratios. Simultaneous high-speed OH* chemiluminescence and particle image velocimetry measurements suggested that increasing swirl intensity resulted in more compact flame shapes and expanded the recirculation zone, which promoted flame stability at higher NH3 ratios. However, under specified conditions, enhancing swirl intensity could increase the instability frequency and amplitude of pressure oscillations. The flame dynamics exhibited different behaviors depending on the swirl intensity. At high swirl intensity, the flames underwent high-frequency, small-amplitude periodic motion. At low swirl intensity, the flames oscillated axially with large amplitude and low frequency. For flow dynamics, the stability of the vortex at high swirl intensity contrasted with the periodic vortex shedding at low swirl intensity. Furthermore, the two-dimensional Rayleigh index indicated that the dominant positive thermoacoustic coupling regions were located near the flame shear layers and flame tail at low and high swirl intensities, respectively. Finally, the experimental results showed that swirl intensity affected pollutant emissions by influencing the temperature of combustion chamber and gas mixing efficiency. The pathway of fuel-type NOx was found to be dominant in the NOx emission of the NH3/CH4/air flames.
|
|
| 20. |
- Mendelson, Michael M., et al.
(författare)
-
Association of Body Mass Index with DNA Methylation and Gene Expression in Blood Cells and Relations to Cardiometabolic Disease : A Mendelian Randomization Approach
- 2017
-
Ingår i: PLoS Medicine. - : PUBLIC LIBRARY SCIENCE. - 1549-1277 .- 1549-1676. ; 14:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background The link between DNA methylation, obesity, and adiposity-related diseases in the general population remains uncertain. Methods and Findings We conducted an association study of body mass index (BMI) and differential methylation for over 400,000 CpGs assayed by microarray in whole-blood-derived DNA from 3,743 participants in the Framingham Heart Study and the Lothian Birth Cohorts, with independent replication in three external cohorts of 4,055 participants. We examined variations in whole blood gene expression and conducted Mendelian randomization analyses to investigate the functional and clinical relevance of the findings. We identified novel and previously reported BMI-related differential methylation at 83 CpGs that replicated across cohorts; BMI-related differential methylation was associated with concurrent changes in the expression of genes in lipid metabolism pathways. Genetic instrumental variable analysis of alterations in methylation at one of the 83 replicated CpGs, cg11024682 (intronic to sterol regulatory element binding transcription factor 1 [SREBF1]), demonstrated links to BMI, adiposity-related traits, and coronary artery disease. Independent genetic instruments for expression of SREBF1 supported the findings linking methylation to adiposity and cardiometabolic disease. Methylation at a substantial proportion (16 of 83) of the identified loci was found to be secondary to differences in BMI. However, the cross-sectional nature of the data limits definitive causal determination. Conclusions We present robust associations of BMI with differential DNA methylation at numerous loci in blood cells. BMI-related DNA methylation and gene expression provide mechanistic insights into the relationship between DNA methylation, obesity, and adiposity-related diseases.
|
|
