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| 2. |
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- 2019
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Tidskriftsartikel (refereegranskat)
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| 3. |
- 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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| 4. |
- Menkveld, Albert J., et al.
(författare)
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Nonstandard Errors
- 2024
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Ingår i: JOURNAL OF FINANCE. - : Wiley-Blackwell. - 0022-1082 .- 1540-6261. ; 79:3, s. 2339-2390
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Tidskriftsartikel (refereegranskat)abstract
- In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty-nonstandard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for more reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants.
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| 5. |
- Chen, Baoqing, et al.
(författare)
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The Long Noncoding RNA CCAT2 Induces Chromosomal Instability Through BOP1-AURKB Signaling
- 2020
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Ingår i: Gastroenterology. - : Elsevier BV. - 0016-5085 .- 1528-0012. ; 159:6, s. 2146-2162
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Tidskriftsartikel (refereegranskat)abstract
- Background & AimsChromosomal instability (CIN) is a carcinogenesis event that promotes metastasis and resistance to therapy by unclear mechanisms. Expression of the colon cancer–associated transcript 2 gene (CCAT2), which encodes a long noncoding RNA (lncRNA), associates with CIN, but little is known about how CCAT2 lncRNA regulates this cancer enabling characteristic.MethodsWe performed cytogenetic analysis of colorectal cancer (CRC) cell lines (HCT116, KM12C/SM, and HT29) overexpressing CCAT2 and colon organoids from C57BL/6N mice with the CCAT2 transgene and without (controls). CRC cells were also analyzed by immunofluorescence microscopy, γ-H2AX, and senescence assays. CCAT2 transgene and control mice were given azoxymethane and dextran sulfate sodium to induce colon tumors. We performed gene expression array and mass spectrometry to detect downstream targets of CCAT2 lncRNA. We characterized interactions between CCAT2 with downstream proteins using MS2 pull-down, RNA immunoprecipitation, and selective 2′-hydroxyl acylation analyzed by primer extension analyses. Downstream proteins were overexpressed in CRC cells and analyzed for CIN. Gene expression levels were measured in CRC and non-tumor tissues from 5 cohorts, comprising more than 900 patients.ResultsHigh expression of CCAT2 induced CIN in CRC cell lines and increased resistance to 5-fluorouracil and oxaliplatin. Mice that expressed the CCAT2 transgene developed chromosome abnormalities, and colon organoids derived from crypt cells of these mice had a higher percentage of chromosome abnormalities compared with organoids from control mice. The transgenic mice given azoxymethane and dextran sulfate sodium developed more and larger colon polyps than control mice given these agents. Microarray analysis and mass spectrometry indicated that expression of CCAT2 increased expression of genes involved in ribosome biogenesis and protein synthesis. CCAT2 lncRNA interacted directly with and stabilized BOP1 ribosomal biogenesis factor (BOP1). CCAT2 also increased expression of MYC, which activated expression of BOP1. Overexpression of BOP1 in CRC cell lines resulted in chromosomal missegregation errors, and increased colony formation, and invasiveness, whereas BOP1 knockdown reduced viability. BOP1 promoted CIN by increasing the active form of aurora kinase B, which regulates chromosomal segregation. BOP1 was overexpressed in polyp tissues from CCAT2 transgenic mice compared with healthy tissue. CCAT2 lncRNA and BOP1 mRNA or protein were all increased in microsatellite stable tumors (characterized by CIN), but not in tumors with microsatellite instability compared with nontumor tissues. Increased levels of CCAT2 lncRNA and BOP1 mRNA correlated with each other and with shorter survival times of patients.ConclusionsWe found that overexpression of CCAT2 in colon cells promotes CIN and carcinogenesis by stabilizing and inducing expression of BOP1 an activator of aurora kinase B. Strategies to target this pathway might be developed for treatment of patients with microsatellite stable colorectal tumors.
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| 6. |
- Li, Guoshuai, et al.
(författare)
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Site selection of desert solar farms based on heterogeneous sand flux
- 2024
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Ingår i: npj Climate and Atmospheric Science. - 2397-3722. ; 7:1
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Tidskriftsartikel (refereegranskat)abstract
- Site selection for building solar farms in deserts is crucial and must consider the dune threats associated with sand flux, such as sand burial and dust contamination. Understanding changes in sand flux can optimize the site selection of desert solar farms. Here we use the ERA5-Land hourly wind data with 0.1° × 0.1° resolution to calculate the yearly sand flux from 1950 to 2022. The mean of sand flux is used to score the suitability of global deserts for building solar farms. We find that the majority of global deserts have low flux potential (≤ 40 m3 m-1 y-1) and resultant flux potential (≤ 2.0 m3 m-1 y-1) for the period 1950–2022. The scoring result demonstrates that global deserts have obvious patchy distribution of site suitability for building solar farms. Our study contributes to optimizing the site selection of desert solar farms, which aligns with the United Nations sustainability development goals for achieving affordable and clean energy target by 2030.
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| 7. |
- Pan, Liang, et al.
(författare)
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a A Resistance-Switchable and Ferroelectric Metal Organic Framework
- 2014
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 0002-7863 .- 1520-5126. ; 136:50, s. 17477-17483
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Tidskriftsartikel (refereegranskat)abstract
- The ever-emerging demands on miniaturization of electronic devices have pushed the development of innovative materials with desired properties. One major endeavor is the development of organic- or organic-inorganic hybrid-based electronics as alternatives or supplements to silicon-based devices. Herein we report the first observation of the coexistence of resistance switching and ferroelectricity in a metal-organic framework (MOF) material, [InC16H11N2O8]center dot 1.5H(2)O, denoted as RSMOF-1. The electrical resistance of RSMOF-1 can be turned on and off repeatedly with a current ratio of 30. A first-principles molecular dynamics simulation suggests that the resistive switching effect is related to the ferroelectric transition of N center dot center dot center dot H-O center dot center dot center dot H-N bridge-structured dipoles of the guest water molecules and the amino-tethered MOF nanochannel. The discovery of the resistive switching effect and ferroelectricity in MOFs offers great potential for the physical implementation of novel electronics for next-generation digital processing and communication.
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| 8. |
- Wain, Louise V., et al.
(författare)
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Novel Blood Pressure Locus and Gene Discovery Using Genome-Wide Association Study and Expression Data Sets From Blood and the Kidney
- 2017
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Ingår i: Hypertension. - 0194-911X .- 1524-4563. ; 70:3, s. e4-e19
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Tidskriftsartikel (refereegranskat)abstract
- Elevated blood pressure is a major risk factor for cardiovascular disease and has a substantial genetic contribution. Genetic variation influencing blood pressure has the potential to identify new pharmacological targets for the treatment of hypertension. To discover additional novel blood pressure loci, we used 1000 Genomes Project-based imputation in 150 134 European ancestry individuals and sought significant evidence for independent replication in a further 228 245 individuals. We report 6 new signals of association in or near HSPB7, TNXB, LRP12, LOC283335, SEPT9, and AKT2, and provide new replication evidence for a further 2 signals in EBF2 and NFKBIA. Combining large whole-blood gene expression resources totaling 12 607 individuals, we investigated all novel and previously reported signals and identified 48 genes with evidence for involvement in blood pressure regulation that are significant in multiple resources. Three novel kidney-specific signals were also detected. These robustly implicated genes may provide new leads for therapeutic innovation.
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| 9. |
- Wang, Hui, et al.
(författare)
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On the Structure of alpha-BiFeO3
- 2013
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Ingår i: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 52:5, s. 2388-2392
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Tidskriftsartikel (refereegranskat)abstract
- Polycrystalline and monocrystalline alpha-BiFeO3 crystals have been synthesized by solid state reaction and flux growth method, respectively. X-ray, neutron, and electron diffraction techniques are used to study the crystallographic and magnetic structure of alpha-BiFeO3. The present data show that alpha-BiFeO3 crystallizes in space group PI with a = 0.563 17(1) nm, b = 0.563 84(1) nm, c = 0.563 70(1) nm, alpha = 59.33(1)degrees, beta = 59.35(1)degrees, gamma = 59.38(1)degrees, and the magnetic structure of alpha-BiFeO3 can be described by space group PI with magnetic modulation vector in reciprocal space q = 0.0045a* - 0.0045b*, which is the magnetic structure model proposed by I. Sosnowska(1) applied to the new PI crystal symmetry of alpha-BiFeO3
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| 10. |
- Xu, Ke Jun, et al.
(författare)
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Bogoliubov quasiparticle on the gossamer Fermi surface in electron-doped cuprates
- 2023
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Ingår i: Nature Physics. - : Springer Nature. - 1745-2473 .- 1745-2481. ; 19:12, s. 1834-1840
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Tidskriftsartikel (refereegranskat)abstract
- Electron-doped cuprates consistently exhibit strong antiferromagnetic correlations, leading to the prevalent belief that antiferromagnetic spin fluctuations mediate Cooper pairing in these unconventional superconductors. However, early investigations showed that although antiferromagnetic spin fluctuations create the largest pseudogap at hot spots in momentum space, the superconducting gap is also maximized at these locations. This presented a paradox for spin-fluctuation-mediated pairing: Cooper pairing is strongest at momenta where the normal-state low-energy spectral weight is most suppressed. Here we investigate this paradox and find evidence that a gossamer—meaning very faint—Fermi surface can provide an explanation for these observations. We study Nd2–xCexCuO4 using angle-resolved photoemission spectroscopy and directly observe the Bogoliubov quasiparticles. First, we resolve the previously observed reconstructed main band and the states gapped by the antiferromagnetic pseudogap around the hot spots. Within the antiferromagnetic pseudogap, we also observe gossamer states with distinct dispersion, from which coherence peaks of Bogoliubov quasiparticles emerge below the superconducting critical temperature. Moreover, the direct observation of a Bogoliubov quasiparticle permits an accurate determination of the superconducting gap, yielding a maximum value an order of magnitude smaller than the pseudogap, establishing the distinct nature of these two gaps. We propose that orientation fluctuations in the antiferromagnetic order parameter are responsible for the gossamer states.
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