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21.
Forrest SR 《Nature》2004,428(6986):911-918
Organic electronics are beginning to make significant inroads into the commercial world, and if the field continues to progress at its current, rapid pace, electronics based on organic thin-film materials will soon become a mainstay of our technological existence. Already products based on active thin-film organic devices are in the market place, most notably the displays of several mobile electronic appliances. Yet the future holds even greater promise for this technology, with an entirely new generation of ultralow-cost, lightweight and even flexible electronic devices in the offing, which will perform functions traditionally accomplished using much more expensive components based on conventional semiconductor materials such as silicon.  相似文献   
22.
Peumans P  Uchida S  Forrest SR 《Nature》2003,425(6954):158-162
The power conversion efficiency of small-molecular-weight and polymer organic photovoltaic cells has increased steadily over the past decade. This progress is chiefly attributable to the introduction of the donor-acceptor heterojunction that functions as a dissociation site for the strongly bound photogenerated excitons. Further progress was realized in polymer devices through use of blends of the donor and acceptor materials: phase separation during spin-coating leads to a bulk heterojunction that removes the exciton diffusion bottleneck by creating an interpenetrating network of the donor and acceptor materials. The realization of bulk heterojunctions using mixtures of vacuum-deposited small-molecular-weight materials has, on the other hand, posed elusive: phase separation induced by elevating the substrate temperature inevitably leads to a significant roughening of the film surface and to short-circuited devices. Here, we demonstrate that the use of a metal cap to confine the organic materials during annealing prevents the formation of a rough surface morphology while allowing for the formation of an interpenetrating donor-acceptor network. This method results in a power conversion efficiency 50 per cent higher than the best values reported for comparable bilayer devices, suggesting that this strained annealing process could allow for the formation of low-cost and high-efficiency thin film organic solar cells based on vacuum-deposited small-molecular-weight organic materials.  相似文献   
23.
Retroviral transduction of T-cell antigen receptor beta-chain and myc genes   总被引:2,自引:0,他引:2  
R Fulton  D Forrest  R McFarlane  D Onions  J C Neil 《Nature》1987,326(6109):190-194
Support for multistage models of oncogenesis has been provided by several highly leukaemogenic retrovirus isolates that have transduced more than one host cell gene. Where functional studies have been performed, these retroviral oncogenes show synergy for in vitro transformation and leukaemogenesis. In naturally occurring feline leukaemias associated with feline leukaemia virus (FeLV), retroviral transduction of myc is a frequent oncogenic mechanism. But evidence suggesting that the FeLV v-myc genes might be insufficient for leukaemogenesis was provided by the latency (12 weeks) and clonality of FeLV/v-myc-induced tumours and the absence of demonstrable in vitro transformation by these viruses. In the search for secondary leukaemogenic events in FeLV/v-myc tumours, we have identified a case of FeLV transduction of a T-cell antigen receptor beta-chain gene. The proviruses carrying this gene (which we have named v-tcr) were a separate population from those carrying v-myc. In its normal role, the T-cell receptor beta-chain forms part of a multimeric complex involved in antigen recognition and T-cell activation. We suggest that v-tcr is a novel viral oncogene which assisted v-myc in the genesis of a naturally occurring case of thymic lymphosarcoma.  相似文献   
24.
25.
Population genomics of human gene expression   总被引:1,自引:0,他引:1  
Genetic variation influences gene expression, and this variation in gene expression can be efficiently mapped to specific genomic regions and variants. Here we have used gene expression profiling of Epstein-Barr virus-transformed lymphoblastoid cell lines of all 270 individuals genotyped in the HapMap Consortium to elucidate the detailed features of genetic variation underlying gene expression variation. We find that gene expression is heritable and that differentiation between populations is in agreement with earlier small-scale studies. A detailed association analysis of over 2.2 million common SNPs per population (5% frequency in HapMap) with gene expression identified at least 1,348 genes with association signals in cis and at least 180 in trans. Replication in at least one independent population was achieved for 37% of cis signals and 15% of trans signals, respectively. Our results strongly support an abundance of cis-regulatory variation in the human genome. Detection of trans effects is limited but suggests that regulatory variation may be the key primary effect contributing to phenotypic variation in humans. We also explore several methodologies that improve the current state of analysis of gene expression variation.  相似文献   
26.
使用非侵害性根吸收硝酸盐检测系统,在较低NO3-浓度下,测定10 m mol/L的蔗糖、葡萄糖、果糖、半乳糖、棉子糖、D-甘露醇、甘露糖、阿拉伯糖、乳糖对水稻品种"汕优63"硝酸盐吸收的影响,以10 min为间隔连续测定4 h,结果表明:加入蔗糖后对水稻硝酸盐的吸收有显著的、立即的、持续的促进作用,与加入蔗糖前相比,硝酸盐净吸收率上升了298%,葡萄糖、半乳糖、果糖、棉子糖对水稻硝酸盐的吸收亦有明显的促进作用,上升幅度140%~223%;乳糖、D-甘露醇、阿拉伯糖无明显影响;甘露糖则有抑制作用.蔗糖可能足作为主要的信号分子参与植物硝酸盐吸收的正反馈调控.  相似文献   
27.
With respect to the problem that index value is ofter given in the form of interval linguistic assessment information in the dynamic multiple attribute group decision making, a novel dynamic grey incidence group decision making methodology based on interval two tuple linguistic information is proposed. Firstly, the algorithms and properties of the interval two tuple linguistic information are used to aggregate the information evaluation matrix. Secondly, the positive and negative ideal schemes for each time period are designed in order to deal with the problem that the expert weights and time weights are known, while index weights are unknown, so that the multi objective programming model with the minimum deviation of the grey incidence degree between each scheme and the positive ideal scheme for each stage is built to determine the index weights. Thirdly, the grey incidence each stage degree with interval two tuple linguistic information between each scheme and the positive and negative ideal scheme for each stage is calculated to establish the optimization model of the optimal membership degree for scheme, so that the expressions form of the optimal membership degree for scheme is determined to solve the optimal membership degree for scheme. Finally, an example validates the feasibility and effectiveness of the novel model. The results show that the proposed method can more precisely deal with the language information and avoid information distortion and loss based on the previous method of processing the language.  相似文献   
28.
A polymer/semiconductor write-once read-many-times memory   总被引:1,自引:0,他引:1  
Möller S  Perlov C  Jackson W  Taussig C  Forrest SR 《Nature》2003,426(6963):166-169
Organic devices promise to revolutionize the extent of, and access to, electronics by providing extremely inexpensive, lightweight and capable ubiquitous components that are printed onto plastic, glass or metal foils. One key component of an electronic circuit that has thus far received surprisingly little attention is an organic electronic memory. Here we report an architecture for a write-once read-many-times (WORM) memory, based on the hybrid integration of an electrochromic polymer with a thin-film silicon diode deposited onto a flexible metal foil substrate. WORM memories are desirable for ultralow-cost permanent storage of digital images, eliminating the need for slow, bulky and expensive mechanical drives used in conventional magnetic and optical memories. Our results indicate that the hybrid organic/inorganic memory device is a reliable means for achieving rapid, large-scale archival data storage. The WORM memory pixel exploits a mechanism of current-controlled, thermally activated un-doping of a two-component electrochromic conducting polymer.  相似文献   
29.
Zusammenfassung Anhydroryanodol besitzt eine den Strukturen I, II oder III entsprechende Laktonformel. Die Struktur des Ryanodols ist in der allgemeinen Formulierung XVII-XIX enthalten. Das Problem der Ryanodolbiogenese wird kurz diskutiert.

The contribution of all our collaborators will be discussed in several papers to be published in the near future.  相似文献   
30.
Résumé On a pu isoler le déshydrodiisoeugénol de l'arille deMyristica fragrans Houtt. (fleur de muscade).

Acknowledgments. The authors wish to express their thanks to Dr.W. D. Jamieson and MrD. Embree of the Atlantic Regional Laboratory for the mass spectroscopic data and to Dr.E. von Rudloff and Mr.W. C. Haid of the Prairie Regional Laboratory (Saskatoon) for the 100 MHz NMR data.  相似文献   
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