| 1. |
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| 2. |
- 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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| 3. |
- 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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| 4. |
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- 2019
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Tidskriftsartikel (refereegranskat)
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| 5. |
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| 6. |
- Zhao, Li-Juan, et al.
(författare)
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Lysine demethylase LSD1 delivered via small extracellular vesicles promotes gastric cancer cell stemness
- 2021
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Ingår i: EMBO Reports. - : EMBO. - 1469-221X .- 1469-3178. ; 22:8
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Tidskriftsartikel (refereegranskat)abstract
- Several studies have examined the functions of nucleic acids in small extracellular vesicles (sEVs). However, much less is known about the protein cargos of sEVs and their functions in recipient cells. This study demonstrates the presence of lysine-specific demethylase 1 (LSD1), which is the first identified histone demethylase, in the culture medium of gastric cancer cells. We show that sEVs derived from gastric cancer cells and the plasma of patients with gastric cancer harbor LSD1. The shuttling of LSD1-containing sEVs from donor cells to recipient gastric cancer cells promotes cancer cell stemness by positively regulating the expression of Nanog, OCT4, SOX2, and CD44. Additionally, sEV-delivered LSD1 suppresses oxaliplatin response of recipient cells in vitro and in vivo, whereas LSD1-depleted sEVs do not. Taken together, we demonstrate that LSD1-loaded sEVs can promote stemness and chemoresistance to oxaliplatin. These findings suggest that the LSD1 content of sEV could serve as a biomarker to predict oxaliplatin response in gastric cancer patients.
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| 7. |
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| 8. |
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| 9. |
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| 10. |
- Ariyawansa, Hiran A., et al.
(författare)
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Fungal diversity notes 111–252—taxonomic and phylogenetic contributions to fungal taxa
- 2015
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Ingår i: Fungal diversity. - : Springer Science and Business Media LLC. - 1560-2745 .- 1878-9129. ; 75, s. 27-274
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Tidskriftsartikel (refereegranskat)abstract
- This paper is a compilation of notes on 142 fungal taxa, including five new families, 20 new genera, and 100 new species, representing a wide taxonomic and geographic range. The new families, Ascocylindricaceae, Caryosporaceae and Wicklowiaceae (Ascomycota) are introduced based on their distinct lineages and unique morphology. The new Dothideomycete genera Pseudomassariosphaeria (Amniculicolaceae), Heracleicola, Neodidymella and P s e u d o m i c ros p h a e r i o p s i s ( D id y m e l l a c e a e ) , P s e u d o p i t h o m y c e s ( D i d y m o s p h a e r i a c e a e ) , Brunneoclavispora, Neolophiostoma and Sulcosporium (Halotthiaceae), Lophiohelichrysum (Lophiostomataceae), G a l l i i c o l a , Popul o c re s c e n t i a a nd Va g i c o l a (Phaeosphaeriaceae), Ascocylindrica (Ascocylindricaceae), E l o n g a t o p e d i c e l l a t a ( R o u s s o e l l a c e a e ) , Pseudoasteromassaria (Latoruaceae) and Pseudomonodictys (Macrodiplodiopsidaceae) are introduced. The newly described species of Dothideomycetes (Ascomycota) are Pseudomassariosphaeria bromicola (Amniculicolaceae), Flammeascoma lignicola (Anteagloniaceae), Ascocylindrica marina (Ascocylindricaceae) , Lembosia xyliae (Asterinaceae), Diplodia crataegicola and Diplodia galiicola ( B o t r yosphae r i a cea e ) , Caryospor a aquat i c a (Caryosporaceae), Heracleicola premilcurensis and Neodi dymell a thai landi cum (Didymellaceae) , Pseudopithomyces palmicola (Didymosphaeriaceae), Floricola viticola (Floricolaceae), Brunneoclavispora bambusae, Neolophiostoma pigmentatum and Sulcosporium thailandica (Halotthiaceae), Pseudoasteromassaria fagi (Latoruaceae), Keissleriella dactylidicola (Lentitheciaceae), Lophiohelichrysum helichrysi (Lophiostomataceae), Aquasubmersa japonica (Lophiotremataceae) , Pseudomonodictys tectonae (Macrodiplodiopsidaceae), Microthyrium buxicola and Tumidispora shoreae (Microthyriaceae), Alloleptosphaeria clematidis, Allophaeosphaer i a c y t i s i , Allophaeosphae r i a subcylindrospora, Dematiopleospora luzulae, Entodesmium artemisiae, Galiicola pseudophaeosphaeria, Loratospora(Basidiomycota) are introduced together with a new genus Neoantrodiella (Neoantrodiellaceae), here based on both morphology coupled with molecular data. In the class Agaricomycetes, Agaricus pseudolangei, Agaricus haematinus, Agaricus atrodiscus and Agaricus exilissimus (Agaricaceae) , Amanita m e l l e i a l b a , Amanita pseudosychnopyramis and Amanita subparvipantherina (Amanitaceae), Entoloma calabrum, Cora barbulata, Dictyonema gomezianum and Inocybe granulosa (Inocybaceae), Xerocomellus sarnarii (Boletaceae), Cantharellus eucalyptorum, Cantharellus nigrescens, Cantharellus tricolor and Cantharellus variabilicolor (Cantharellaceae), Cortinarius alboamarescens, Cortinarius brunneoalbus, Cortinarius ochroamarus, Cortinarius putorius and Cortinarius seidlii (Cortinariaceae), Hymenochaete micropora and Hymenochaete subporioides (Hymenochaetaceae), Xylodon ramicida (Schizoporaceae), Colospora andalasii (Polyporaceae), Russula guangxiensis and Russula hakkae (Russulaceae), Tremella dirinariae, Tremella graphidis and Tremella pyrenulae (Tremellaceae) are introduced. Four new combinations Neoantrodiella gypsea, Neoantrodiella thujae (Neoantrodiellaceae), Punctulariopsis cremeoalbida, Punctulariopsis efibulata (Punctulariaceae) are also introduced here for the division Basidiomycota. Furthermore Absidia caatinguensis, Absidia koreana and Gongronella koreana (Cunninghamellaceae), Mortierella pisiformis and Mortierella formosana (Mortierellaceae) are newly introduced in the Zygomycota, while Neocallimastix cameroonii and Piromyces irregularis (Neocallimastigaceae) ar e i n t roduced i n the Neocallimastigomycota. Reference specimens or changes in classification and notes are provided for Alternaria ethzedia, Cucurbitaria ephedricola, Austropleospora, Austropleospora archidendri, Byssosphaeria rhodomphala, Lophiostoma caulium, Pseudopithomyces maydicus, Massariosphaeria, Neomassariosphaeria and Pestalotiopsis montellica.
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| 11. |
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| 12. |
- Gaulton, Kyle J, et al.
(författare)
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Genetic fine mapping and genomic annotation defines causal mechanisms at type 2 diabetes susceptibility loci.
- 2015
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 47:12, s. 1415-1415
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Tidskriftsartikel (refereegranskat)abstract
- We performed fine mapping of 39 established type 2 diabetes (T2D) loci in 27,206 cases and 57,574 controls of European ancestry. We identified 49 distinct association signals at these loci, including five mapping in or near KCNQ1. 'Credible sets' of the variants most likely to drive each distinct signal mapped predominantly to noncoding sequence, implying that association with T2D is mediated through gene regulation. Credible set variants were enriched for overlap with FOXA2 chromatin immunoprecipitation binding sites in human islet and liver cells, including at MTNR1B, where fine mapping implicated rs10830963 as driving T2D association. We confirmed that the T2D risk allele for this SNP increases FOXA2-bound enhancer activity in islet- and liver-derived cells. We observed allele-specific differences in NEUROD1 binding in islet-derived cells, consistent with evidence that the T2D risk allele increases islet MTNR1B expression. Our study demonstrates how integration of genetic and genomic information can define molecular mechanisms through which variants underlying association signals exert their effects on disease.
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| 13. |
- Kristan, Matej, et al.
(författare)
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The Visual Object Tracking VOT2015 challenge results
- 2015
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Ingår i: Proceedings 2015 IEEE International Conference on Computer Vision Workshops ICCVW 2015. - : IEEE. - 9780769557205 ; , s. 564-586
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Konferensbidrag (refereegranskat)abstract
- The Visual Object Tracking challenge 2015, VOT2015, aims at comparing short-term single-object visual trackers that do not apply pre-learned models of object appearance. Results of 62 trackers are presented. The number of tested trackers makes VOT 2015 the largest benchmark on short-term tracking to date. For each participating tracker, a short description is provided in the appendix. Features of the VOT2015 challenge that go beyond its VOT2014 predecessor are: (i) a new VOT2015 dataset twice as large as in VOT2014 with full annotation of targets by rotated bounding boxes and per-frame attribute, (ii) extensions of the VOT2014 evaluation methodology by introduction of a new performance measure. The dataset, the evaluation kit as well as the results are publicly available at the challenge website(1).
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| 14. |
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| 15. |
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| 16. |
- Leebens-Mack, James H., et al.
(författare)
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One thousand plant transcriptomes and the phylogenomics of green plants
- 2019
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Ingår i: Nature. - : Nature Publishing Group. - 0028-0836 .- 1476-4687. ; 574:7780, s. 679-
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Tidskriftsartikel (refereegranskat)abstract
- Green plants (Viridiplantae) include around 450,000-500,000 species(1,2) of great diversity and have important roles in terrestrial and aquatic ecosystems. Here, as part of the One Thousand Plant Transcriptomes Initiative, we sequenced the vegetative transcriptomes of 1,124 species that span the diversity of plants in a broad sense (Archaeplastida), including green plants (Viridiplantae), glaucophytes (Glaucophyta) and red algae (Rhodophyta). Our analysis provides a robust phylogenomic framework for examining the evolution of green plants. Most inferred species relationships are well supported across multiple species tree and supermatrix analyses, but discordance among plastid and nuclear gene trees at a few important nodes highlights the complexity of plant genome evolution, including polyploidy, periods of rapid speciation, and extinction. Incomplete sorting of ancestral variation, polyploidization and massive expansions of gene families punctuate the evolutionary history of green plants. Notably, we find that large expansions of gene families preceded the origins of green plants, land plants and vascular plants, whereas whole-genome duplications are inferred to have occurred repeatedly throughout the evolution of flowering plants and ferns. The increasing availability of high-quality plant genome sequences and advances in functional genomics are enabling research on genome evolution across the green tree of life.
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| 17. |
- Machiela, Mitchell J, et al.
(författare)
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Female chromosome X mosaicism is age-related and preferentially affects the inactivated X chromosome
- 2016
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Ingår i: Nature Communications. - : Nature Publishing Group. - 2041-1723. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- To investigate large structural clonal mosaicism of chromosome X, we analysed the SNP microarray intensity data of 38,303 women from cancer genome-wide association studies (20,878 cases and 17,425 controls) and detected 124 mosaic X events >2 Mb in 97 (0.25%) women. Here we show rates for X-chromosome mosaicism are four times higher than mean autosomal rates; X mosaic events more often include the entire chromosome and participants with X events more likely harbour autosomal mosaic events. X mosaicism frequency increases with age (0.11% in 50-year olds; 0.45% in 75-year olds), as reported for Y and autosomes. Methylation array analyses of 33 women with X mosaicism indicate events preferentially involve the inactive X chromosome. Our results provide further evidence that the sex chromosomes undergo mosaic events more frequently than autosomes, which could have implications for understanding the underlying mechanisms of mosaic events and their possible contribution to risk for chronic diseases.
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| 18. |
- Wan, Cheng-Liang, et al.
(författare)
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基于玻璃毛细管的大气环境MeV质子微束的产生与测量 : [Production and measurement of MeV proton microbeams in atmospheric environment based on glass capillary]
- 2024
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Ingår i: Wuli xuebao. - 1000-3290. ; 73:10
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Tidskriftsartikel (refereegranskat)abstract
- 本文采用玻璃毛细管产生了大气环境中工作的2.5 MeV质子外束微束, 并对束斑直径及能量分布随玻璃毛细管与束流方向之间角度(倾角)变化进行测量. 测量结果表明, 在玻璃毛细管轴向与束流方向一致时(倾角为0°), 产生的微束中存在保持初始入射能量的直接穿透部分以及散射部分, 其中直接穿透的质子占比最大, 束斑直径也最大. 随着玻璃毛细管倾角的增大, 当其大于几何张角时, 束斑直径变小, 产生的微束全部为能量减小的散射部分, 直接穿透质子消失. 我们对质子在玻璃毛细管内传输时的内壁散射过程进行了模拟计算及离子轨迹分析, 发现大角度的散射部分决定了形成的外束微束斑外围轮廓, 而束斑中心区域由不与毛细管内壁产生任何作用的直接穿透离子构成, 其大小由玻璃毛细管出口直径以及几何容许张角决定. 采用玻璃毛细管产生的外束微束具有产生简单廉价, 微束区域定位简单的特点, 有望在辐射生物学、医学、材料等领域得到广泛应用.
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| 19. |
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| 20. |
- Albert, Benjamin B., et al.
(författare)
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Supplementation with milk enriched with complex lipids during pregnancy : A double-blind randomized controlled trial
- 2021
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 16:2
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Tidskriftsartikel (refereegranskat)abstract
- Background Gangliosides are a class of sphingolipids that are present in the cell membranes of vertebrates. Gangliosides influence a broad range of cellular processes through effects on signal transduction, being found abundantly in the brain, and having a role in neurodevelopment.Objective We aimed to assess the effects of maternal daily consumption of ganglioside-enriched milk vs non-enriched milk and a non-supplemented group of pregnant women on maternal ganglioside levels and pregnancy outcomes.Design Double-blind parallel randomized controlled trial. Methods 1,500 women aged 20-40 years were recruited in Chongqing (China) between 11 and 14 weeks of a singleton pregnancy, and randomized into three groups: Control-received standard powdered milk formulation (>= 4 mg gangliosides/day); Complex milk lipid-enhanced (CML-E) group-same formulation enriched with complex milk lipids (>= 8 mg gangliosides/day) from milk fat globule membrane; Reference-received no milk. Serum ganglioside levels were measured in a randomly selected subsample of 250 women per group.Results CML-E milk was associated with marginally greater total gangliosides levels in maternal serum compared to Control (13.02 vs 12.69 mu g/ml; p = 0.034) but not to Reference group. CML-E milk did not affect cord blood ganglioside levels. Among the 1500 women, CML-E milk consumption was associated with a lower rate of gestational diabetes mellitus than control milk [relative risk 0.80 (95% CI 0.64, 0.99)], but which was not different to the Reference group. CML-E milk supplementation had no other effects on maternal or newborn health.Conclusions Maternal supplementation with milk fat globule membrane, as a source of gangliosides, was not associated with any adverse health outcomes, and did not increase serum gangliosides compared with the non-supplemented reference group.
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| 21. |
- Arun, K. G., et al.
(författare)
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New horizons for fundamental physics with LISA
- 2022
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Ingår i: Living Reviews in Relativity. - : Springer Science and Business Media LLC. - 1433-8351 .- 2367-3613. ; 25:1
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Forskningsöversikt (refereegranskat)abstract
- The Laser Interferometer Space Antenna (LISA) has the potential to reveal wonders about the fundamental theory of nature at play in the extreme gravity regime, where the gravitational interaction is both strong and dynamical. In this white paper, the Fundamental Physics Working Group of the LISA Consortium summarizes the current topics in fundamental physics where LISA observations of gravitational waves can be expected to provide key input. We provide the briefest of reviews to then delineate avenues for future research directions and to discuss connections between this working group, other working groups and the consortium work package teams. These connections must be developed for LISA to live up to its science potential in these areas.
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| 22. |
- Berndt, Sonja I., et al.
(författare)
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Genome-wide meta-analysis identifies 11 new loci for anthropometric traits and provides insights into genetic architecture
- 2013
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 45:5, s. 501-U69
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Tidskriftsartikel (refereegranskat)abstract
- Approaches exploiting trait distribution extremes may be used to identify loci associated with common traits, but it is unknown whether these loci are generalizable to the broader population. In a genome-wide search for loci associated with the upper versus the lower 5th percentiles of body mass index, height and waist-to-hip ratio, as well as clinical classes of obesity, including up to 263,407 individuals of European ancestry, we identified 4 new loci (IGFBP4, H6PD, RSRC1 and PPP2R2A) influencing height detected in the distribution tails and 7 new loci (HNF4G, RPTOR, GNAT2, MRPS33P4, ADCY9, HS6ST3 and ZZZ3) for clinical classes of obesity. Further, we find a large overlap in genetic structure and the distribution of variants between traits based on extremes and the general population and little etiological heterogeneity between obesity subgroups.
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| 23. |
- Fan, Hong-Qi, et al.
(författare)
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Prognostic value of isolated nocturnal hypertension on ambulatory measurement in 8711 individuals from 10 populations
- 2010
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Ingår i: Journal of Hypertension. - 0263-6352 .- 1473-5598. ; 28:10, s. 2036-2045
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Tidskriftsartikel (refereegranskat)abstract
- Background: We and other investigators previously reported that isolated nocturnal hypertension on ambulatory measurement (INH) clustered with cardiovascular risk factors and was associated with intermediate target organ damage. We investigated whether INH might also predict hard cardiovascular endpoints. Methods and results: We monitored blood pressure (BP) throughout the day and followed health outcomes in 8711 individuals randomly recruited from 10 populations (mean age 54.8 years, 47.0% women). Of these, 577 untreated individuals had INH (daytime BP <135/85 mmHg and night-time BP >=120/70 mmHg) and 994 untreated individuals had isolated daytime hypertension on ambulatory measurement (IDH; daytime BP >=135/85 mmHg and night-time BP <120/70 mmHg). During follow-up (median 10.7 years), 1284 deaths (501 cardiovascular) occurred and 1109 participants experienced a fatal or nonfatal cardiovascular event. In multivariable-adjusted analyses, compared with normotension (n = 3837), INH was associated with a higher risk of total mortality (hazard ratio 1.29, P = 0.045) and all cardiovascular events (hazard ratio 1.38, P = 0.037). IDH was associated with increases in all cardiovascular events (hazard ratio 1.46, P = 0.0019) and cardiac endpoints (hazard ratio 1.53, P = 0.0061). Of 577 patients with INH, 457 were normotensive (<140/90 mmHg) on office BP measurement. Hazard ratios associated with INH with additional adjustment for office BP were 1.31 (P = 0.039) and 1.38 (P = 0.044) for total mortality and all cardiovascular events, respectively. After exclusion of patients with office hypertension, these hazard ratios were 1.17 (P = 0.31) and 1.48 (P = 0.034). Conclusion: INH predicts cardiovascular outcome in patients who are normotensive on office or on ambulatory daytime BP measurement.
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| 24. |
- Felsberg, Michael, et al.
(författare)
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The Thermal Infrared Visual Object Tracking VOT-TIR2015 Challenge Results
- 2015
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Ingår i: Proceedings of the IEEE International Conference on Computer Vision. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781467383905 ; , s. 639-651
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Konferensbidrag (refereegranskat)abstract
- The Thermal Infrared Visual Object Tracking challenge 2015, VOTTIR2015, aims at comparing short-term single-object visual trackers that work on thermal infrared (TIR) sequences and do not apply prelearned models of object appearance. VOT-TIR2015 is the first benchmark on short-term tracking in TIR sequences. Results of 24 trackers are presented. For each participating tracker, a short description is provided in the appendix. The VOT-TIR2015 challenge is based on the VOT2013 challenge, but introduces the following novelties: (i) the newly collected LTIR (Linköping TIR) dataset is used, (ii) the VOT2013 attributes are adapted to TIR data, (iii) the evaluation is performed using insights gained during VOT2013 and VOT2014 and is similar to VOT2015.
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| 25. |
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| 26. |
- Hudson, Thomas J., et al.
(författare)
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International network of cancer genome projects
- 2010
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 464:7291, s. 993-998
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Tidskriftsartikel (refereegranskat)abstract
- The International Cancer Genome Consortium (ICGC) was launched to coordinate large-scale cancer genome studies in tumours from 50 different cancer types and/or subtypes that are of clinical and societal importance across the globe. Systematic studies of more than 25,000 cancer genomes at the genomic, epigenomic and transcriptomic levels will reveal the repertoire of oncogenic mutations, uncover traces of the mutagenic influences, define clinically relevant subtypes for prognosis and therapeutic management, and enable the development of new cancer therapies.
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| 27. |
- Ji, Xuemei, et al.
(författare)
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Identification of susceptibility pathways for the role of chromosome 15q25.1 in modifying lung cancer risk
- 2018
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Ingår i: Nature Communications. - : NATURE PUBLISHING GROUP. - 2041-1723. ; 9, s. 1-15
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Tidskriftsartikel (refereegranskat)abstract
- Genome-wide association studies (GWAS) identified the chromosome 15q25.1 locus as a leading susceptibility region for lung cancer. However, the pathogenic pathways, through which susceptibility SNPs within chromosome 15q25.1 affects lung cancer risk, have not been explored. We analyzed three cohorts with GWAS data consisting 42,901 individuals and lung expression quantitative trait loci (eQTL) data on 409 individuals to identify and validate the underlying pathways and to investigate the combined effect of genes from the identified susceptibility pathways. The KEGG neuroactive ligand receptor interaction pathway, two Reactome pathways, and 22 Gene Ontology terms were identified and replicated to be significantly associated with lung cancer risk, with P values less than 0.05 and FDR less than 0.1. Functional annotation of eQTL analysis results showed that the neuroactive ligand receptor interaction pathway and gated channel activity were involved in lung cancer risk. These pathways provide important insights for the etiology of lung cancer.
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| 28. |
- Jin, Ying-Hui, et al.
(författare)
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Chemoprophylaxis, diagnosis, treatments, and discharge management of COVID-19 : An evidence-based clinical practice guideline (updated version)
- 2020
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Ingår i: Military Medical Research. - : Springer Science and Business Media LLC. - 2054-9369. ; 7:1
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Tidskriftsartikel (refereegranskat)abstract
- The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of a rapidly spreading illness, coronavirus disease 2019 (COVID-19), affecting more than seventeen million people around the world. Diagnosis and treatment guidelines for clinicians caring for patients are needed. In the early stage, we have issued "A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus (2019-nCoV) infected pneumonia (standard version)"; now there are many direct evidences emerged and may change some of previous recommendations and it is ripe for develop an evidence-based guideline. We formed a working group of clinical experts and methodologists. The steering group members proposed 29 questions that are relevant to the management of COVID-19 covering the following areas: chemoprophylaxis, diagnosis, treatments, and discharge management. We searched the literature for direct evidence on the management of COVID-19, and assessed its certainty generated recommendations using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. Recommendations were either strong or weak, or in the form of ungraded consensus-based statement. Finally, we issued 34 statements. Among them, 6 were strong recommendations for, 14 were weak recommendations for, 3 were weak recommendations against and 11 were ungraded consensus-based statement. They covered topics of chemoprophylaxis (including agents and Traditional Chinese Medicine (TCM) agents), diagnosis (including clinical manifestations, reverse transcription-polymerase chain reaction (RT-PCR), respiratory tract specimens, IgM and IgG antibody tests, chest computed tomography, chest x-ray, and CT features of asymptomatic infections), treatments (including lopinavir-ritonavir, umifenovir, favipiravir, interferon, remdesivir, combination of antiviral drugs, hydroxychloroquine/chloroquine, interleukin-6 inhibitors, interleukin-1 inhibitors, glucocorticoid, qingfei paidu decoction, lianhua qingwen granules/capsules, convalescent plasma, lung transplantation, invasive or noninvasive ventilation, and extracorporeal membrane oxygenation (ECMO)), and discharge management (including discharge criteria and management plan in patients whose RT-PCR retesting shows SARS-CoV-2 positive after discharge). We also created two figures of these recommendations for the implementation purpose. We hope these recommendations can help support healthcare workers caring for COVID-19 patients.
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| 29. |
- Kristan, Matej, et al.
(författare)
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The Visual Object Tracking VOT2014 Challenge Results
- 2015
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Ingår i: COMPUTER VISION - ECCV 2014 WORKSHOPS, PT II. - Cham : Springer. - 9783319161808 - 9783319161815 ; , s. 191-217
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Konferensbidrag (refereegranskat)abstract
- The Visual Object Tracking challenge 2014, VOT2014, aims at comparing short-term single-object visual trackers that do not apply pre-learned models of object appearance. Results of 38 trackers are presented. The number of tested trackers makes VOT 2014 the largest benchmark on short-term tracking to date. For each participating tracker, a short description is provided in the appendix. Features of the VOT2014 challenge that go beyond its VOT2013 predecessor are introduced: (i) a new VOT2014 dataset with full annotation of targets by rotated bounding boxes and per-frame attribute, (ii) extensions of the VOT2013 evaluation methodology, (iii) a new unit for tracking speed assessment less dependent on the hardware and (iv) the VOT2014 evaluation toolkit that significantly speeds up execution of experiments. The dataset, the evaluation kit as well as the results are publicly available at the challenge website (http://votchallenge.net).
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| 30. |
- Li, Hong, et al.
(författare)
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A Switchable bis-Branched [1]Rotaxane featuring Dual-Mode Molecular Motions and Tunable Molecular Aggregation
- 2014
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Ingår i: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 6:21, s. 18921-18929
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Tidskriftsartikel (refereegranskat)abstract
- A multifunctional bis-branched [1]rotaxane containing a perylene bisimide (PBI) core and two identical bistable[1]rotaxane arms terminated with ferrocene units was prepared and characterized by H-1 NMR, C-13 NMR, and 2D ROESY NMR spectroscopies and by HR-ESI spectrometry. The system is shown to possess several key features: (1) In acetone solution, external acid base stimuli can result in relative mechanical movements of its ring and thread, which can induce extension and contraction movements of the whole system accompanied by a rotational movement of the ferrocene units, thus realizing dual-mode molecular motions, and the optimized conformations at different states are obtained through molecular dynamics simulations employing the general Amber force field. (2) The introduction of PBI enables the system fluorescence encoding through distance-dependent photoinduced electron transfer process from the ferrocene units to the PBI fluorophore. (3) The addition of Zn2+ can increase the degree of aggregation of the system, while adding base hinders aggregation because of the movement of the macrocyde. The tunable aggregated nanostructural morphologies of [1]rotaxane were examined by scanning electron microscopy. These results can pave the way to achieve precise control of integrated and coupling nanomechanical motions at a single-molecule level and provide more insight into controlling the aggregate behavior of switchable mechanically interlocked molecules.
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| 31. |
- Lin, Qi, et al.
(författare)
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Subject-adaptive Loose-fitting Smart Garment Platform for Human Activity Recognition
- 2023
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Ingår i: ACM transactions on sensor networks. - : Association for Computing Machinery (ACM). - 1550-4867 .- 1550-4859. ; 19:4
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Tidskriftsartikel (refereegranskat)abstract
- The ability to recognize and detect changes in human posture is important in awide range of applications such as health care and human-computer interaction. Achieving this goal using loose-fit garments instrumented with sensors is particularly challenging, due to the complex interaction between garments and human body. Herein we present a method to detect and recognize human posture with casual loose-fitting smart garments integrated with highly sensitive, stretchable, optical transparent, and low-cost strain sensors. By attaching these sensors to an off-the-shelf casual jacket, we developed a smart loose-fitting sensing garment that enables posture recognition using a deep learning model, domain-adaptive Convolutional Neural Networks-Long Short-Term Memory (CNN-LSTM). This deep learning model overcame the noise and variation due to the complex interaction between loose-fitting garments and human body. Considering that users' labeled data are usually not available in the training stage, an additional domain discriminator path on the conventional CNN-LSTM model has been introduced to further improve the adaptability. To evaluate the potential of this loose-fitting smart garment, three case studies were conducted under realistic conditions: recognitions of human activities, stationary postures with random hand movements and slouch. Our results demonstrate the potential of the proposed smart garment system for practical applications.
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| 32. |
- Luo, Yifei, et al.
(författare)
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Technology Roadmap for Flexible Sensors
- 2023
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Ingår i: ACS Nano. - : American Chemical Society. - 1936-0851 .- 1936-086X. ; 17:6, s. 5211-5295
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Forskningsöversikt (refereegranskat)abstract
- Humans rely increasingly on sensors to address grand challenges and to improve quality of life in the era of digitalization and big data. For ubiquitous sensing, flexible sensors are developed to overcome the limitations of conventional rigid counterparts. Despite rapid advancement in bench-side research over the last decade, the market adoption of flexible sensors remains limited. To ease and to expedite their deployment, here, we identify bottlenecks hindering the maturation of flexible sensors and propose promising solutions. We first analyze challenges in achieving satisfactory sensing performance for real-world applications and then summarize issues in compatible sensor-biology interfaces, followed by brief discussions on powering and connecting sensor networks. Issues en route to commercialization and for sustainable growth of the sector are also analyzed, highlighting environmental concerns and emphasizing nontechnical issues such as business, regulatory, and ethical considerations. Additionally, we look at future intelligent flexible sensors. In proposing a comprehensive roadmap, we hope to steer research efforts towards common goals and to guide coordinated development strategies from disparate communities. Through such collaborative efforts, scientific breakthroughs can be made sooner and capitalized for the betterment of humanity.
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| 33. |
- Merino, Jordi, et al.
(författare)
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Quality of dietary fat and genetic risk of type 2 diabetes : individual participant data meta-analysis
- 2019
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Ingår i: BMJ. British Medical Journal. - : BMJ Publishing Group Ltd. - 0959-8146 .- 0959-535X. ; 366
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE To investigate whether the genetic burden of type 2 diabetes modifies the association between the quality of dietary fat and the incidence of type 2 diabetes.DESIGN Individual participant data meta-analysis.DATA SOURCES Eligible prospective cohort studies were systematically sourced from studies published between January 1970 and February 2017 through electronic searches in major medical databases (Medline, Embase, and Scopus) and discussion with investigators.REVIEW METHODS Data from cohort studies or multicohort consortia with available genome-wide genetic data and information about the quality of dietary fat and the incidence of type 2 diabetes in participants of European descent was sought. Prospective cohorts that had accrued five or more years of follow-up were included. The type 2 diabetes genetic risk profile was characterized by a 68-variant polygenic risk score weighted by published effect sizes. Diet was recorded by using validated cohort-specific dietary assessment tools. Outcome measures were summary adjusted hazard ratios of incident type 2 diabetes for polygenic risk score, isocaloric replacement of carbohydrate (refined starch and sugars) with types of fat, and the interaction of types of fat with polygenic risk score.RESULTS Of 102 305 participants from 15 prospective cohort studies, 20 015 type 2 diabetes cases were documented after a median follow-up of 12 years (interquartile range 9.4-14.2). The hazard ratio of type 2 diabetes per increment of 10 risk alleles in the polygenic risk score was 1.64 (95% confidence interval 1.54 to 1.75, I-2 = 7.1%, tau(2) = 0.003). The increase of polyunsaturated fat and total omega 6 polyunsaturated fat intake in place of carbohydrate was associated with a lower risk of type 2 diabetes, with hazard ratios of 0.90 (0.82 to 0.98, I-2 = 18.0%, tau(2) = 0.006; per 5% of energy) and 0.99 (0.97 to 1.00, I-2 = 58.8%, tau(2) = 0.001; per increment of 1 g/d), respectively. Increasing monounsaturated fat in place of carbohydrate was associated with a higher risk of type 2 diabetes (hazard ratio 1.10, 95% confidence interval 1.01 to 1.19, I-2 = 25.9%, tau(2) = 0.006; per 5% of energy). Evidence of small study effects was detected for the overall association of polyunsaturated fat with the risk of type 2 diabetes, but not for the omega 6 polyunsaturated fat and monounsaturated fat associations. Significant interactions between dietary fat and polygenic risk score on the risk of type 2 diabetes (P>0.05 for interaction) were not observed.CONCLUSIONS These data indicate that genetic burden and the quality of dietary fat are each associated with the incidence of type 2 diabetes. The findings do not support tailoring recommendations on the quality of dietary fat to individual type 2 diabetes genetic risk profiles for the primary prevention of type 2 diabetes, and suggest that dietary fat is associated with the risk of type 2 diabetes across the spectrum of type 2 diabetes genetic risk.
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| 34. |
- Ni, Yuan Qi, et al.
(författare)
-
Infant-phase reddening by surface Fe-peak elements in a normal type Ia supernova
- 2022
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Ingår i: Nature Astronomy. - : Springer Science and Business Media LLC. - 2397-3366. ; 6:5, s. 568-576
-
Tidskriftsartikel (refereegranskat)abstract
- Type Ia supernovae are thermonuclear explosions of white dwarf stars. They play a central role in the chemical evolution of the Universe and are an important measure of cosmological distances. However, outstanding questions remain about their origins. Despite extensive efforts to obtain natal information from their earliest signals, observations have thus far failed to identify how the majority of them explode. Here, we present infant-phase detections of SN 2018aoz from a very low brightness of −10.5 AB absolute magnitude, revealing a hitherto unseen plateau in the B band that results in a rapid redward colour evolution between 1.0 and 12.4 hours after the estimated epoch of first light. The missing B-band flux is best explained by line-blanket absorption from Fe-peak elements in the outer 1% of the ejected mass. The observed B − V colour evolution of the supernova also matches the prediction from an over-density of Fe-peak elements in the same outer 1% of the ejected mass, whereas bluer colours are expected from a purely monotonic distribution of Fe-peak elements. The presence of excess nucleosynthetic material in the extreme outer layers of the ejecta points to enhanced surface nuclear burning or extended subsonic mixing processes in some normal type Ia SN explosions.
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| 35. |
- Ni, Yuan Qi, et al.
(författare)
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The Origin and Evolution of the Normal Type Ia SN 2018aoz with Infant-phase Reddening and Excess Emission
- 2023
-
Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 946:1
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Tidskriftsartikel (refereegranskat)abstract
- SN 2018aoz is a Type Ia SN with a B-band plateau and excess emission in infant-phase light curves ≲1 day after the first light, evidencing an over-density of surface iron-peak elements as shown in our previous study. Here, we advance the constraints on the nature and origin of SN 2018aoz based on its evolution until the nebular phase. Near-peak spectroscopic features show that the SN is intermediate between two subtypes of normal Type Ia: core normal and broad line. The excess emission may be attributable to the radioactive decay of surface iron-peak elements as well as the interaction of ejecta with either the binary companion or a small torus of circumstellar material. Nebular-phase limits on Hα and He i favor a white dwarf companion, consistent with the small companion size constrained by the low early SN luminosity, while the absence of [O I] and He i disfavors a violent merger of the progenitor. Of the two main explosion mechanisms proposed to explain the distribution of surface iron-peak elements in SN 2018aoz, the asymmetric Chandrasekhar-mass explosion is less consistent with the progenitor constraints and the observed blueshifts of nebular-phase [Fe II] and [Ni II]. The helium-shell double-detonation explosion is compatible with the observed lack of C spectral features, but current 1D models are incompatible with the infant-phase excess emission, Bmax–Vmax color, and weak strength of nebular-phase [Ca II]. Although the explosion processes of SN 2018aoz still need to be more precisely understood, the same processes could produce a significant fraction of Type Ia SNe that appear to be normal after ∼1 day.
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| 36. |
- Park, Jong-Sun, et al.
(författare)
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Auroral electrojet activity for long-duration radial interplanetary magnetic field events
- 2023
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Ingår i: Journal of Geophysical Research - Space Physics. - : American Geophysical Union (AGU). - 2169-9380 .- 2169-9402. ; 128:3
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we provide statistical evidence that the level of solar wind-magnetosphere-ionosphere (SW-M-I) coupling is weaker under radial (Sun-Earth component dominant) interplanetary magnetic field (IMF) conditions than non-radial IMF conditions. This is performed by analyzing auroral electrojet activity (using SuperMAG auroral electrojet indices) in the sunlit and dark ionospheres for long-duration (at least 4 hr) radial IMF events and comparing against the same for long-duration azimuthal (dusk-dawn component dominant) IMF events. We show that the north-south IMF component (IMF Bz) plays a crucial role in controlling the level of auroral electrojet activity as a negative half-wave rectifier even for both IMF orientation categories. However, it is found that the magnitudes of the auroral electrojet indices are generally lower for radial IMF than for azimuthal IMF under similar sets of solar wind (radial bulk velocity and number density) and IMF Bz conditions, regardless of whether these indices are derived in the sunlit or dark regions. Moreover, the efficiency of coupling functions is lower for radial IMF than for azimuthal IMF, implying that increased coupling strength due to the azimuthal IMF component alone cannot well explain weaker auroral electrojets during radial IMF periods. Lastly, the contribution of the radial IMF component itself to auroral electrojet activity is also lower compared to the azimuthal IMF component. Our results suggest that the level of SW-M-I coupling characterized by auroral electrojet activity can be modulated by the radial IMF component, although the effect of this component is weaker than the other two IMF components.
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| 37. |
- Park, Jong-Sun, et al.
(författare)
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Radial Interplanetary Magnetic Field-Induced North-South Asymmetry in the Solar Wind-Magnetosphere-Ionosphere Coupling : A Case Study
- 2022
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Ingår i: Journal of Geophysical Research - Space Physics. - : John Wiley & Sons. - 2169-9380 .- 2169-9402. ; 127:2
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present a case study of the radial interplanetary magnetic field (IMF Bx)-induced asymmetric solar wind-magnetosphere-ionosphere (SW-M-I) coupling between the northern and southern polar caps using ground-based and satellite-based data. Under prolonged conditions of strong earthward IMF on 5 March 2015, we find significant discrepancies between polar cap north (PCN) and polar cap south (PCS) magnetic indices with a negative bay-like change in the PCN and a positive bay-like change in the PCS. The difference between these indices (PCN-PCS) reaches a minimum of −1.63 mV/m, which is approximately three times higher in absolute value than the values for most of the time on this day (within ±0.5 mV/m). The high-latitude plasma convection also shows an asymmetric feature such that there exists an additional convection cell near the noon sector in the northern polar cap, but not in the southern polar cap. Meanwhile, negative bays in the north-south component of ground magnetic field perturbations (less than 50 nT) observed in the nightside auroral region of the Northern Hemisphere are accompanied with the brightening and widening of the nightside auroral oval in the Southern Hemisphere, implying a weak, but clear energy transfer to the nightside ionosphere of both hemispheres. After the hemispheric asymmetries in the polar caps disappear, a substorm onset takes place. All these observations indicate that IMF Bx-induced single lobe reconnection that occurred in the Northern Hemisphere plays an important role in hemispheric asymmetry in the energy transfer from the solar wind to the polar cap through the magnetosphere.
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| 38. |
- Park, Jong-Sun, et al.
(författare)
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Statistical features of polar cap North and South indices in response to interplanetary and terrestrial conditions : a revisit
- 2024
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Ingår i: Space Weather. - : American Geophysical Union (AGU). - 1542-7390. ; 22:4
-
Tidskriftsartikel (refereegranskat)abstract
- In this study, we investigate statistical features of polar cap north (PCN) and south (PCS) indices in response to various interplanetary conditions (interplanetary magnetic field [IMF] orientation in three-dimensions) and terrestrial conditions (seasonal and magnetic local time [MLT] locations of the index stations). The concurrent PCN-PCS pairs for 1998–2002 and 2004–2018 are divided based on their sign type (positive-positive, negative-negative, negative-positive, and positive-negative PCN-PCS pairs) and time coverage (the times when both index stations are in the dawn/dusk MLT sector during northern summer/winter). Analyzing the IMF orientation dependence on the occurrence probabilities of concurrent indices and on the differences between the indices in various sign types for each time coverage reveals that the statistical features in PCN-PCS pairs obtained in the dawn MLT sector can be largely explained by the effects of the three-component IMF (related to the polar cap convection patterns) combined with season (related to the hemispheric asymmetry in solar illumination-induced ionospheric conductance). However, those obtained in the dusk MLT sector are controlled dominantly by seasonal effects rather than IMF orientation effects. Our findings indicate that PCN-PCS pair data provide local views about the solar wind-magnetosphere-ionosphere (SW-M-I) coupling system with different control efficiencies of IMF orientation and season depending on the MLT location of the stations. Therefore, introducing polar cap indices recorded simultaneously at various locations in both hemispheres and analyzing them are strongly required to infer global views of the coupled SW-M-I system in the open field regions with higher confidence.
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| 39. |
- Park, Jong-Sun, et al.
(författare)
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Transpolar Arcs During a Prolonged Radial Interplanetary Magnetic Field Interval
- 2021
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Ingår i: Journal of Geophysical Research - Space Physics. - : John Wiley & Sons. - 2169-9380 .- 2169-9402. ; 126:6
-
Tidskriftsartikel (refereegranskat)abstract
- Transpolar arcs (TPAs) are believed to predominantly occur under northward interplanetary magnetic field (IMF) conditions with their hemispheric asymmetry controlled by the Sun-Earth (radial) component of the IMF. In this study, we present observations of TPAs that appear in both the northern and southern hemispheres even during a prolonged interval of radially oriented IMF. The Defense Meteorological Satellite Program (DMSP) F16 and the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellites observed TPAs on the dawnside polar cap in both hemispheres (one TPA structure in the southern hemisphere and two in the northern hemisphere) during an interval of nearly earthward-oriented IMF on October 29, 2005. The southern hemisphere TPA and one of the northern hemisphere TPAs are associated with electron and ion precipitation and mostly sunward plasma flow (with shears) relative to their surroundings. Meanwhile, the other TPA in the northern hemisphere is associated with an electron-only precipitation and antisunward flow relative to its surroundings. Our observations indicate the following: (a) the TPA formation is not limited to northward IMF conditions; (b) the TPAs can be located on both closed field lines rooted in the polar cap of both hemispheres and open field lines connected to the northward field lines draped over one hemisphere of the magnetopause. We believe that the TPAs presented here are the result of both indirect and direct processes of solar wind energy transfer to the high-latitude ionosphere.
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| 40. |
- Qi, Z., et al.
(författare)
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Application of nonlinear principal component analysis technique to nuclear power plants
- 2019
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Ingår i: International Conference on Nuclear Engineering, Proceedings, ICONE. - : ASME Press. - 9784888982566
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Konferensbidrag (refereegranskat)abstract
- Traditionally, manual calibration of sensors is required and performed during each refueling outage. If the traditional time-directed calibration is replaced by an online monitoring technique, the maintenance cost will be significantly reduced since only the abnormal sensors identified in on-line monitoring need to be re-calibrated or replaced off-line. The Nonlinear Principal Component Analysis (NLPCA), such as Auto-Associative Neural Network (AANN) and Auto-Associative Kernel Principal Component Analysis (AAKPCA), can describe the nonlinear correlation between sensors such as power, temperature, pressure and flowrate. In this paper, AANN and AAKPCA model are tested by simulated redundant data and Tennessee-Eastman process data. The results show that both of them have a high ability of prediction and a low sensitivity. Therefore, they are can be used in on-line monitoring.
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| 41. |
- Qi, Z., et al.
(författare)
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Sensor fault detection in nuclear power plant using auto-associative neural network
- 2019
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Ingår i: International Conference on Nuclear Engineering, Proceedings, ICONE. - : American Society of Mechanical Engineers (ASME). - 9784888983051
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Konferensbidrag (refereegranskat)abstract
- Fault diagnosis system usually includes a prediction module and a diagnosis module. The prediction module is supposed to predict sensor values based on sensor observations, and the diagnosis module is used to determine whether a sensor has degradation or failure by comparing the difference between sensor observations and predictions. Auto-Associative Neural Network (AANN) is a widely applied data-driven prediction method consisting of input layer, mapping layer, bottleneck layer, de-mapping layer and output layer. AANN compresses the information contained in the input data (i.e. sensor observations) into bottleneck layer through mapping layer, and then reconstructs the sensor values at output layer based on the extracted nonlinear features stored in bottleneck layer through de-mapping layer. This paper focuses on the feasibility study of AANN model in fault diagnosis for nuclear power plants. The performance of AANN model was studied by using simulation data, and the AANN model was optimized by combining prejudgment and secondary prediction. The results show that the optimized AANN model can improve the performance comparing to original AANN model, and can be applied to the fault diagnosis for nuclear power plant sensors.
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| 42. |
- Qian, Li-Bing, et al.
(författare)
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Transmission of electrons through the conical glass capillary with the grounded conducting outer surface
- 2017
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Ingår i: Wuli xuebao. - : Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences. - 1000-3290. ; 66:12
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Tidskriftsartikel (refereegranskat)abstract
- The transmission of 1.5 keV-electrons through a conical glass capillary is reported. This study aims to understand the so-called guiding effect for the negatively charged particles (e.g. electrons). The guiding mechanism is understood quite well with positively charged particles in particular highly charged ions, but not clear with electrons, i. e., even the basic scheme mediated by the existence of negative charge patches to guide the electrons is still somewhat controversial.. The study of the charging-up dynamics causing the electrons transport inside the capillary will shed light on this issue. In order to perform this, a data acquisition system has been setup to follow the time evolution of the two-dimensional angular distribution of the transmitted electrons. The electrons are detected by the multi-channel plate (MCP) detector with a phosphor screen. The image from the phosphor screen is recorded by a charge-coupled device camera. The timing signals for the detected events are extracted from the back stack of the MCP detector and recorded by the data acquisition system, synchronized with the acquired images. The electron beam has a size of 0.5 mm x 0.5 mm and a divergence of less than 0.35.. The inner diameter of the straight part of the capillary is 1.2 mm and the exit diameter is 225 mu m. A small conducting aperture of 0.3 mm in diameter is placed at the entrance of the capillary. Two-dimensional angular distribution of the transmitted electrons through conical glass capillary and its time evolution are measured. The results show that the transmission rate decreases and reaches to a constant value for the completely discharged glass capillary with time going by. The centroid of the angular distribution moves to an asymptotic value while the width remains unchanged. These transmission characteristics are different from those indicated in our previous work (2016 Acta Phys: Si n: 65 204103). The difference originates from the different manipulations of the capillary outer surface. A conducting layer is coated on the outer surface of the capillary and grounded in this work. This isolates various discharge/charge channels and forms a new stable discharge channel. The transmission rate as a function of the tilt angle shows that the allowed transmission occurs at the tilt angle limited by the geometrical factors, i. e., the geometrical opening angle given by the aspect ratio as well as the beam divergence. The transmission characteristics suggest that most likely there are formed no negative patches to facilitate the electron transmission through the glass capillary at this selected beam energy. It is different from that of highly charged ions, where the formation of the charge patches prohibits the close collisions between the following ions and guides them out of the capillary.
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| 43. |
- Qu, Chang, et al.
(författare)
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Functional significance of asymmetrical retention of parental alleles in a hybrid pine species complex
- 2024
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Ingår i: Journal of Systematics and Evolution. - : John Wiley & Sons. - 1674-4918 .- 1759-6831. ; 62:1, s. 135-148
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Tidskriftsartikel (refereegranskat)abstract
- Hybrid genomes usually harbor asymmetrical parental contributions. However, it is challenging to infer the functional significance of asymmetrical retention of parental alleles in hybrid populations of conifer trees. Here we investigated the diversity in the glutathione S-transferase (GST) gene family in a hybrid pine Pinus densata and its parents (Pinus tabuliformis and Pinus yunnanensis). Plant GSTs play major roles in protecting plants against biotic and abiotic stresses. In this study, 19 orthologous groups of GST genes were identified and cloned from these three species. We examined their expression in different tissues, and then purified the corresponding proteins to characterize their enzymatic activities and specificities toward different substrates. We found that among the 19 GST orthologous groups, divergence in gene expression and in enzymatic activities toward different substrates was prevalent. P. densata preferentially retained P. yunnanensis-like GSTs for 17 out of the 19 gene loci. We determined the first GST crystal structure from conifer species at a resolution of 2.19 Å. Based on this structure, we performed site-directed mutagenesis to replace amino acid residuals in different wild-types of GSTs to understand their functional impacts. Reciprocal replacement of amino acid residuals in native GSTs of P. densata and P. tabuliformis demonstrated significant changes in enzyme functions and identified key sites controlling GSTs activities. This study illustrates an approach to evaluating the functional significance of sequence variations in conifer genomes. Our study also sheds light on plausible mechanisms for controlling the selective retention of parental alleles in the P. densata genome.
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| 44. |
- Sun, Jia-Qi, et al.
(författare)
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Spatholobus suberectus Column Extract Inhibits Estrogen Receptor Positive Breast Cancer via Suppressing ER MAPK PI3K/AKT Pathway
- 2016
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Ingår i: Evidence-based Complementary and Alternative Medicine. - : Hindawi Limited. - 1741-427X .- 1741-4288.
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Tidskriftsartikel (refereegranskat)abstract
- Although Chinese herbal compounds have long been alternatively applied for cancer treatment in China, their treatment effects have not been sufficiently investigated. The Chinese herb Spatholobus suberectus is commonly prescribed to cancer patients. HPLC analysis has shown that the main components of Spatholobus suberectus are flavonoids that can be classified as phytoestrogens, having a structure similar to estrogen. This study was designed to investigate the effects of Spatholobus suberectus column extract (SSCE) on the estrogen receptor-positive (ER+) breast cancer cell line MCF-7 and its possible molecular mechanism. In our study, MTT assay was performed to evaluate cell viability. The results show that SSCE (80, 160, and 320 mu g/ml) significantly decreased the viability of MCF-7 cells. SSCE also triggered apoptosis, arrested the cell cycle at the G0/G1 phase, and inhibited cell migration. A dual-luciferase reporter system showed that SSCE suppressed intranuclear p-ER activity; Western blot analysis confirmed the repressed expression of phosphorylated-ER alpha (p-ER alpha), ERK1/2, p-ERK1/2, AKT, p-AKT, p-mTOR, PI3K, and p-PI3K, indicating that SSCE suppressed the MAPK PI3K/AKT signaling pathway. Collectively, our results suggest that SSCE causes apoptosis, an arrest in the G0/G1 phase, and a decrease in migration in ER+ MCF-7 cells via hypoactivity of the ER and suppression of the MAPK PI3K/AKT pathway.
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| 45. |
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| 46. |
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| 47. |
- Wan, Cheng-Liang, et al.
(författare)
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Dynamics of slow electrons transmitting through straight glass capillary and tapered glass capillary
- 2016
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Ingår i: Wuli xuebao. - : Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences. - 1000-3290. ; 65:20
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Tidskriftsartikel (refereegranskat)abstract
- It has been found that the transmission rate of the electrons through insulating capillaries as a function of time/incident charge is not the same as that of the ions. The question arises that by using the electrons, if the negative charge patches can be formed to facilitate the transmission of the following electrons, thereby substantiating that the so-called guiding effect works also for electrons. This study aims to observe the time evolutions of the transmission of electrons through a straight glass tube and a tapered glass capillary. This will reveal the details of how and (or) if the negative charge patches can be formed when the electrons transport through them. In this work, a set of MCP/phosphor two-dimensional detection system based on Labview platform is developed to obtain the time evolution of the angular distribution of the transmitted electrons. The pulsed electron beams are obtained to test our detection system. The time evolution of the angular profile of 1.5 keV electrons transmitting through the glass tube/capillary is observed. The transmitted electrons are observed on the detector for a very short time and disappear for a time and then appear again for both the glass tube and tapered glass capillary, leading to an oscillation. The positive charge patches are formed in the insulating glass tube and tapered glass capillary since the secondary electron emission coefficient for the incident energy is larger than 1. It is due to the fact that fast discharge of the deposited charge leads to the increase of the transmission rate, while the fast blocking of the incident electrons due to the deposited positive charge leads to the decrease of the transmission rate. The geometrical configuration of the taper glass capillary tends to make the secondary electrons deposited at the exit part to form the negative patches that facilitate the transmission of electrons. This suggests that if the stable transmission needs to be reached for producing the electron micro-beam by using tapered glass capillaries, the steps must be taken to have the proper grounding and shielding of the glass capillaries and tubes. Our results show a difference in transmission through the insulating capillary between electrons and highly charged ions.
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| 48. |
- Wang, Yu-Cheng, et al.
(författare)
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Porous Carbon Membrane-Supported Atomically Dispersed Pyrrole-Type Fe-N-4 as Active Sites for Electrochemical Hydrazine Oxidation Reaction
- 2020
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Ingår i: Small. - : Wiley. - 1613-6810 .- 1613-6829. ; 16:31
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Tidskriftsartikel (refereegranskat)abstract
- The rational design of catalytically active sites in porous materials is essential in electrocatalysis. Herein, atomically dispersed Fe-N-x sites supported by hierarchically porous carbon membranes are designed to electrocatalyze the hydrazine oxidation reaction (HzOR), one of the key techniques in electrochemical nitrogen transformation. The high intrinsic catalytic activity of the Fe-N-x single-atom catalyst together with the uniquely mixed micro-/macroporous membrane support positions such an electrode among the best-known heteroatom-based carbon anodes for hydrazine fuel cells. Combined with advanced characterization techniques, electrochemical probe experiments, and density functional theory calculation, the pyrrole-type Fe-N-4 structure is identified as the real catalytic site in HzOR.
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| 49. |
- Winestrand, Sandra, et al.
(författare)
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Oxalate decarboxylase of Trametes versicolor : biochemical characterization and performance in bleaching filtrates from the pulp and paper industry
- 2012
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Ingår i: Journal of chemical technology and biotechnology (1986). - : Wiley. - 0268-2575 .- 1097-4660. ; 87:11, s. 1600-1606
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Oxalate decarboxylase (ODC) from acid-induced cultures of the white-rot fungus Trametes versicolor was purified and characterized with respect to its biochemical properties and the possibility to utilize the enzyme for treatment of process water with the intention to prevent problems with calcium-oxalate scaling in the pulp and paper industry. RESULTS: Purified T. versicolor ODC was identified by tandem mass spectrometry. As estimated by using SDS-PAGE, the molecular mass was 69 kDa, and 60 kDa after deglycosylation with N-glycosidase F. The pH optimum was 2.5 and the temperature optimum was 4045 degrees C. The effects of ten potential inhibitors in industrial filtrates were examined. The enzyme was sensitive to low concentrations (0.1 mmol L-1) of chlorite and sulfite. T. versicolor ODC exhibited activity in 16 filtrates collected from mechanical pulping and kraft pulping. It had higher activity than ODC from Aspergillus niger in all of the filtrates and higher activity than oxalate oxidase from barley in all filtrates except two. CONCLUSIONS: The investigation shows basic biochemical properties of T. versicolor ODC and indicates that the enzyme may be useful for treatment of industrial filtrates under acidic conditions. Copyright (c) 2012 Society of Chemical Industry
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- Wu, Ai Ping, et al.
(författare)
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The factors affecting a native obligate parasite, Cuscuta australis, in selecting an exotic weed, Humulus scandens, as its host
- 2019
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- In weed management, using native parasites to control exotic weeds is considered a better alternative than classical biological control. But the risk must be assessed because of the potential damage caused by these agents. We conducted this project to investigate the mechanism driving the choice of a native obligate parasite, Cuscuta australis, between the exotic, Humulus scandens, and native plants as its host through field and pot experiments. The results showed that C. australis preferred the exotic weed over native (naturalized) hosts and caused a notable reduction in the biomass of H. scandens in the field. In contrast, the results of the pot experimentindicated that C. australis preferred a mix of native (naturalized) hosts over the exotic weed. Both texperiments indicated that the parasitic preference of C. australis was induced more by light irradiance than plant water, carbon (C), nitrogen (N) and phosphorus (P) contents, indicating that the native parasite can only be used to control H. scandens when the exotic weed forms mono-cultures or dominates the community. Accordingly, induction and release of C. australis to control H. scandens should be conducted with great caution.
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