| 11. |
- Chen, Chun Lin, et al.
(författare)
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In situ TEM observation of decomposition of high-purity sapphire
- 2009
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Ingår i: Philosophical Magazine Letters. - : Informa UK Limited. - 0950-0839 .- 1362-3036. ; 89:2, s. 113-119
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Tidskriftsartikel (refereegranskat)abstract
- The decomposition of agr-Al2O3 under 200 keV electron irradiation has been investigated by in situ high-resolution electron microscopy (HREM). It was confirmed that aluminium precipitated from agr-Al2O3 under 200 keV electron irradiation for less than 1 min over the temperature range from 700 to 1273 K. The electron dose rate was of the order of 1023 e m-2 s-1 and the vacuum level of the microscope was better than 10-6 Pa. The mechanisms of agr-Al2O3 decomposition were discussed based on two possible decomposition models: the thermally activated atom movement and the forced atom displacement
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| 12. |
- Chien, Ming-Hsien, et al.
(författare)
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Vascular endothelial growth factor-C (VEGF-C) promotes angiogenesis by induction of COX-2 in leukemic cells via the VEGF-R3/JNK/AP-1 pathway.
- 2009
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Ingår i: Carcinogenesis. - : Oxford University Press (OUP). - 0143-3334 .- 1460-2180. ; 30:12, s. 2005-13
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Tidskriftsartikel (refereegranskat)abstract
- Vascular endothelial growth factor (VEGF)-C is recognized as a tumor lymphangiogenic factor based on the effects of activated VEGF-R3 on lymphatic endothelial cells. Many tumor cells express VEGF-R3 but the function of this receptor in tumor cells is largely unknown. It has been reported that the VEGF-C/VEGF-R3 axis is activated in subsets of leukemia patients. Herein, we have shown that VEGF-C induces angiogenic activity in the tube formation assay invitro and Matrigel plug assay in vivo by upregulating an angiogenic factor, cyclooxygenase-2 (COX-2), through VEGF-R3 in the human acute myeloid leukemia (AML) cell line, THP-1. COX-2 induction by VEGF-C was also observed in other VEGF-R3(+) human AML cell lines (U937 and HL60). Moreover, immunohistochemical analysis of bone marrow specimens of 37 patients diagnosed with AML revealed that VEGF-C expression in specimens was associated with the expression of COX-2 (P < 0.001). The manner by which signaling pathways transduced by VEGF-C is responsible for COX-2 upregulation was further investigated. Blocking the p42/44 mitogen-activated protein kinase (MAPK) pathway with the MAPK kinase inhibitor, PD 98059, failed to inhibit VEGF-C-mediated COX-2 expression. However, VEGF-C-induced COX-2 upregulation was effectively abolished by overexpression of dominant-negative c-Jun N-terminal kinase (JNK) or treatment with the JNK inhibitor, SP 600125. VEGF-C induced JNK-dependent nuclear translocation of c-Jun. Furthermore, chromatin immunoprecipitation and reporter assays revealed that VEGF-C enhanced c-Jun binding to the cyclic adenosine 3',5'-monophosphate-response element of the COX-2 promoter and induced COX-2 expression. In sum, the data herein highlight the pathogenic role of VEGF-C in leukemia via regulation of angiogenesis through upregulation of COX-2.
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| 13. |
- Ding, Li, et al.
(författare)
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Somatic mutations affect key pathways in lung adenocarcinoma
- 2008
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 455:7216, s. 1069-1075
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Tidskriftsartikel (refereegranskat)abstract
- Determining the genetic basis of cancer requires comprehensive analyses of large collections of histopathologically well-classified primary tumours. Here we report the results of a collaborative study to discover somatic mutations in 188 human lung adenocarcinomas. DNA sequencing of 623 genes with known or potential relationships to cancer revealed more than 1,000 somatic mutations across the samples. Our analysis identified 26 genes that are mutated at significantly high frequencies and thus are probably involved in carcinogenesis. The frequently mutated genes include tyrosine kinases, among them the EGFR homologue ERBB4; multiple ephrin receptor genes, notably EPHA3; vascular endothelial growth factor receptor KDR; and NTRK genes. These data provide evidence of somatic mutations in primary lung adenocarcinoma for several tumour suppressor genes involved in other cancers--including NF1, APC, RB1 and ATM--and for sequence changes in PTPRD as well as the frequently deleted gene LRP1B. The observed mutational profiles correlate with clinical features, smoking status and DNA repair defects. These results are reinforced by data integration including single nucleotide polymorphism array and gene expression array. Our findings shed further light on several important signalling pathways involved in lung adenocarcinoma, and suggest new molecular targets for treatment.
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| 14. |
- Fu, J., et al.
(författare)
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Trends in graded precipitation in China from 1961 to 2000
- 2008
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Ingår i: Advances in atmospheric Sciences. - : Springer Science and Business Media LLC. - 1861-9533 .- 0256-1530. ; 25:2, s. 267-278
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Tidskriftsartikel (refereegranskat)abstract
- Daily precipitation rates observed at 576 stations in China from 1961 to 2000 were classified into six grades of intensity, including trace (no amount), slight (<= 1 mm d(-1)), small, large, heavy, and very heavy. The last four grades together constitute the so called effective precipitation (> 1 mm d(-)1). The spatial distribution and temporal trend of the graded precipitation days are examined. A decreasing trend in trace precipitation days is observed for the whole of China, except at several sites in the south of the middle section of the Yangtze River, while a decreasing trend in slight precipitation days only appears in eastern China. The decreasing trend and interannual variability of trace precipitation days is consistent with the warming trend and corresponding temperature variability in China for the same period, indicating a possible role played by increased surface air temperature in cloud formation processes. For the effective precipitation days, a decreasing trend is observed along the Yellow River valley and for the middle reaches of the Yangtze River and Southwest China, while an increasing trend is found for Xinjiang, the eastern Tibetan Plateau, Northeast China and Southeast China. The decreasing trend of effective precipitation days for the middle-lower Yellow River valley and the increasing trend for the lower Yangtze River valley are most likely linked to anomalous monsoon circulation in East China. The most important contributor to the trend in effective precipitation depends upon the region concerned.
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| 15. |
- Fu, Ying, et al.
(författare)
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Design of semiconductor CdSe core ZnS/CdS multishell quantum dots for multiphoton applications
- 2007
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 90:17, s. 173102-1-173102-3
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Tidskriftsartikel (refereegranskat)abstract
- Optical properties of colloidal II-VI semiconductor CdSe cores with ZnS and CdS multishell quantum dots (QDs) have been studied by experimental characterization and theoretical analysis. Due to the large number of energy states densely compacted in both conduction and valence bands of the quantum dots, strong interband and intraband optical couplings are induced by the multiphoton excitation, implicating an efficient fluorescence of such II-VI-based core-multishell CdSe QDs. This fact in combination with the advantage of the size tolerance of II-VI QDs with respect to the narrow fluorescence bandwidth make these systems excellent candidates for applications using fluorescence induced by multiphoton excitation.
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| 16. |
- Gao, S-W, et al.
(författare)
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Enhanced NEH method in solving permutation flow shop problem
- 2007
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Ingår i: Shanghai Jiaotong University. Journal. - 1007-1172. ; 12E:1, s. 47-52
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Tidskriftsartikel (refereegranskat)abstract
- This paper proposed an enhanced NEH with full insertion moves to solve the permutation flow shop problem. The characteristics of the original NEH are investigated and analyzed, and it is concluded that the given method would be promising to find better solutions, while the cost would be increased. Fast makespan calculating method and eliminating non-promising permutation policy are introduced to reduce the evaluation effort. The former decreases the time complexity from O(n4m) to O(n3m), which is an acceptable cost for medium and small size instances considering the obtained solution quality. The results from computational experience show that the latter also can eliminate a lot of non-promising solutions.
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| 17. |
- Garcia-Closas, Montserrat, et al.
(författare)
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Heterogeneity of breast cancer associations with five susceptibility loci by clinical and pathological characteristics
- 2008
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Ingår i: PLoS genetics. - : Public Library of Science (PLoS). - 1553-7404. ; 4:4, s. e1000054-
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Tidskriftsartikel (refereegranskat)abstract
- A three-stage genome-wide association study recently identified single nucleotide polymorphisms (SNPs) in five loci (fibroblast growth receptor 2 (FGFR2), trinucleotide repeat containing 9 (TNRC9), mitogen-activated protein kinase 3 K1 (MAP3K1), 8q24, and lymphocyte-specific protein 1 (LSP1)) associated with breast cancer risk. We investigated whether the associations between these SNPs and breast cancer risk varied by clinically important tumor characteristics in up to 23,039 invasive breast cancer cases and 26,273 controls from 20 studies. We also evaluated their influence on overall survival in 13,527 cases from 13 studies. All participants were of European or Asian origin. rs2981582 in FGFR2 was more strongly related to ER-positive (per-allele OR (95%CI) = 1.31 (1.27-1.36)) than ER-negative (1.08 (1.03-1.14)) disease (P for heterogeneity = 10(-13)). This SNP was also more strongly related to PR-positive, low grade and node positive tumors (P = 10(-5), 10(-8), 0.013, respectively). The association for rs13281615 in 8q24 was stronger for ER-positive, PR-positive, and low grade tumors (P = 0.001, 0.011 and 10(-4), respectively). The differences in the associations between SNPs in FGFR2 and 8q24 and risk by ER and grade remained significant after permutation adjustment for multiple comparisons and after adjustment for other tumor characteristics. Three SNPs (rs2981582, rs3803662, and rs889312) showed weak but significant associations with ER-negative disease, the strongest association being for rs3803662 in TNRC9 (1.14 (1.09-1.21)). rs13281615 in 8q24 was associated with an improvement in survival after diagnosis (per-allele HR = 0.90 (0.83-0.97). The association was attenuated and non-significant after adjusting for known prognostic factors. Our findings show that common genetic variants influence the pathological subtype of breast cancer and provide further support for the hypothesis that ER-positive and ER-negative disease are biologically distinct. Understanding the etiologic heterogeneity of breast cancer may ultimately result in improvements in prevention, early detection, and treatment.
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| 18. |
- Haeger-Eugensson, Marie, et al.
(författare)
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Spridning av föroreningar till luft från bränder
- 2008
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Detta projekt är en del av en större studie med övergripande syftet att ta fram en metod för beräkning av emissioner från bränder samt användande av dessa till spridningsberäkningar både till luft och vatten. Resultat från luftemissionsdelen har använts som indata till de beräkningar genomförda i detta delprojekt vars syfte varit att testa hur dispersion och haltnivåer kan skilja sig beroende på val av modell, definiera styrande brand- och meteorologiska parametrarna, för deposition och halt i luft och att utveckla och testa en metod för generaliserade spridningsberäknigar för bränder genom statistiskt bearbetade resultat från ett års beräkningar för olika meteorologiska klasser. Det har hittills varit svårt att spridningsberäkna bränder med avancerade spridningsmodeller eftersom nödvändiga indata inte funnits. Fokus har istället legat på att återge brandförloppet bra medan meteorologi, och därmed dispersionen, varit förenklad. Vi har inte funnit utred-ningar som visar om enklare modeller eller generaliseringar av befintliga brandmodeller utgör ett tillräckligt bra underlag för snabb bedömning av miljö- och hälsoeffekter från bränder. Beräkningarna i detta projekt är genomförda med TAPM-modellen under olika årstider som medel- och maximala dygnsvärden samt av dygnsdeposition av PM10 för respektive plymriktning. Medelvärdena används för bedömning av miljöpåverkan och maximala dygnshalter för mer akuta hälsoeffekter för att utforma och förebyggande åtgärder, både akut och långsiktigt (t.ex. stadsplanering). Förhållandet mellan max- och medelhalter varierar beroende på säsong och spridningsförutsättningar, med maxhalten ca 50 ggr högre och med stor variation. Haltnivåerna i centrum- respektive kransplymerna är båda ca 200 µg/m3 även om emissionen är ca 5 ggr högre i cen-trumplymen jämfört med de sammanlagda emissionerna från kransplymerna. Skälet är att den högre centrumplymen sprids mer effektivt till följd av den dubbelt så höga vindhastigheten på hög nivå. Validering av beräknade haltnivåer och plymlyft har visat att med brandindata från en brandmodell har spridningen av PM10 återgets väl med TAPM -modellen. Beräkningarna är även tänkta att vara bas för utveckling av en modell anpassad för användande under fältmässiga förhållanden för att snabbt få fram beslutsunderlag för åtgärder vid olyckor (som evakuering) och därmed förebygga och minimera skador på t.ex. miljön och människors hälsa.
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| 19. |
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| 20. |
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