| 1. |
- Bianchi, Marco, et al.
(författare)
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Robust Surface Doping of Bi2Se3 by Rubidium Intercalation
- 2012
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Ingår i: ACS Nano. - : American Chemical Society (ACS). - 1936-086X .- 1936-0851. ; 6:8, s. 7009-7015
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Tidskriftsartikel (refereegranskat)abstract
- Rubidium adsorption on the surface of the topological insulator Bi2Se3 is found to induce a strong downward band bending, leading to the appearance of a quantum-confined two-dimensional electron gas state (2DEG) in the conduction band. The 2DEG shows a strong Rashba-type spin orbit splitting, and it has previously been pointed out that this has relevance to nanoscale spintronics devices. The adsorption of Rb atoms, on the other hand, renders the surface very reactive, and exposure to oxygen leads to a rapid degrading of the 2DEG. We show that intercalating the Rb atoms, presumably into the van der Waals gaps in the quintuple layer structure of Bi2Se3, drastically reduces the surface reactivity while not affecting the promising electronic structure. The intercalation process is observed above room temperature and accelerated with increasing initial Rb coverage, an effect that is ascribed to the Coulomb interaction between the charged Rb ions. Coulomb repulsion is also thought to be responsible for a uniform distribution of Rb on the surface.
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| 2. |
- Feng, Chungang, et al.
(författare)
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A cis-Regulatory Mutation of PDSS2 Causes Silky-Feather in Chickens
- 2014
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Ingår i: PLOS Genetics. - : Public Library of Science (PLoS). - 1553-7390 .- 1553-7404. ; 10:8, s. e1004576-
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Tidskriftsartikel (refereegranskat)abstract
- Silky-feather has been selected and fixed in some breeds due to its unique appearance. This phenotype is caused by a single recessive gene (hookless, h). Here we map the silky-feather locus to chromosome 3 by linkage analysis and subsequently fine-map it to an 18.9 kb interval using the identical by descent (IBD) method. Further analysis reveals that a C to G transversion located upstream of the prenyl (decaprenyl) diphosphate synthase, subunit 2 (PDSS2) gene is causing silky-feather. All silky-feather birds are homozygous for the G allele. The silky-feather mutation significantly decreases the expression of PDSS2 during feather development in vivo. Consistent with the regulatory effect, the C to G transversion is shown to remarkably reduce PDSS2 promoter activity in vitro. We report a new example of feather structure variation associated with a spontaneous mutation and provide new insight into the PDSS2 function.
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| 3. |
- Wang, Peng-Fei, et al.
(författare)
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A novel self-refreshable capacitorless DRAM cell and its extended applications
- 2010
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Ingår i: Solid-State Electronics. - : Elsevier BV. - 0038-1101 .- 1879-2405. ; 54:9, s. 985-990
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Tidskriftsartikel (refereegranskat)abstract
- A novel DRAM cell based on floating junction gate (FJG) concept is investigated for its extended applications. Compared to the two-transistor floating gate DRAM cell, the new memory cell investigated in the present work has a much simpler configuration with only one transistor. Besides, its write speed is improved by introducing an integrated gated-diode so that state “1” can be self-refreshable. In this paper, the device configuration, the DRAM application feasibility, the self-refreshing ability, and the non-destructive read are explored. In addition, extended applications of the DRAM cell using the FJG concept will be discussed.
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| 4. |
- Weinstein, John N., et al.
(författare)
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The cancer genome atlas pan-cancer analysis project
- 2013
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 45:10, s. 1113-1120
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Forskningsöversikt (refereegranskat)abstract
- The Cancer Genome Atlas (TCGA) Research Network has profiled and analyzed large numbers of human tumors to discover molecular aberrations at the DNA, RNA, protein and epigenetic levels. The resulting rich data provide a major opportunity to develop an integrated picture of commonalities, differences and emergent themes across tumor lineages. The Pan-Cancer initiative compares the first 12 tumor types profiled by TCGA. Analysis of the molecular aberrations and their functional roles across tumor types will teach us how to extend therapies effective in one cancer type to others with a similar genomic profile. © 2013 Nature America, Inc. All rights reserved.
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| 5. |
- Yang, Tien-Nan, et al.
(författare)
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Variations in monsoonal rainfall over the last 21 kyr inferred from sedimentary organic matter in Tung-Yuan Pond, southern Taiwan
- 2011
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Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 30:23-24, s. 3413-3422
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Tidskriftsartikel (refereegranskat)abstract
- Changes in paleorainfall intensity linked to the strength of the East Asian (EA) summer monsoon since 21 cal kyr BP are inferred from the organic matter contents of a 15-m sediment core from Tung-Yuan Pond in southern Taiwan. High total organic carbon/total nitrogen (TOC/TN) values in association with increased TOC content suggest that more soil-derived material containing terrestrial organic matter (OM) was delivered to the lake during periods of increased runoff associated with extensive precipitation that resulted from intensified summer monsoons, whereas low values indicate OM possessing a dominant algal origin during weakened summer monsoons. Rainfall intensity in terms of the proportion of terrestrial OM was high in four periods: the last deglaciation (similar to 17.2 to similar to 12.2 ka), the early Holocene (similar to 10.6 to similar to 8.6 ka), the middle Holocene Thermal Optimum (similar to 7.7 to similar to 5 ka) and the late Holocene (similar to 4.2 to similar to 2 ka), whereas it was low in the intervening time periods. High TOC/TN values coincide with peak values of summer insolation, and thus the strongest EA summer monsoon during the early and middle Holocene: small drops in these ratios correspond to increasing and decreasing solar radiation in the deglacial period and the late Holocene, respectively. The four intervals with low TOC/TN ratios, as well as episodic drops of the ratios during the deglaciation and the early and late Holocene are concordant with the late last glacial (similar to 21 to similar to 17.2 ka), the Oldest (similar to 14.8 ka), the Older (similar to 13.3 ka) and the Younger Dryas (similar to 13 to similar to 11.5 ka), the 8.2 cold event (similar to 8.6-7.7 ka) and a late Holocene cold event (similar to 5-4.2 ka), and suggest a weakened EA summer monsoon during these times. Moreover, high frequency hydrological variability occurred during the early Holocene, heavy rainfall persisted during the middle Holocene, and precipitation intensity generally diminished after similar to 5 ka. The Tung-Yuan Pond sediment record indicates that the TOC/TN ratio can be used as a paleorainfall intensity proxy to trace variations in the EA summer monsoon strength in other small lakes. Crown Copyright
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