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排序方式: 共有428条查询结果,搜索用时 15 毫秒
41.
In 2007 Ireland supplied 96% of the total energy demand with fossil fuels (7% domestic and 89% imported) and 3% with renewable energy, even though there are enough renewable resources to supply all the energy required. As energy prices increase and the effects of global warming worsen, it is essential that Ireland begins to utilise its renewable resources more effectively. Therefore, this study presents the first step towards a 100% renewable energy-system for Ireland. The energy-system analysis tool used was EnergyPLAN, as it accounts for all sectors of the energy-system that need to be considered when integrating large penetrations of renewable energy: the electricity, heat, and transport sectors. Initially, a reference model of the existing Irish energy-system was constructed, and subsequently three different 100% renewable energy-systems were created with each focusing on a different resource: biomass, hydrogen, and electricity. These energy-systems were compared so that the benefits from each could be used to create an ‘optimum’ scenario called combination. Although the results illustrate a potential 100% renewable energy-system for Ireland, they have been obtained based on numerous assumptions. Therefore, these will need to be improved in the future before a serious roadmap can be defined for Ireland’s renewable energy transition. 相似文献
42.
L Hacein-Bey ES Connolly SA Mayer WL Young J Pile-Spellman RA Solomon 《Canadian Metallurgical Quarterly》1998,43(6):1304-12; discussion 1312-3
OBJECTIVE: Endovascular management of complex intracranial aneurysms is increasingly being considered as an alternative to standard surgical clipping. However, little attention has been paid to the complementary nature of surgery and endovascular therapy. METHODS: Between September 1992 and May 1997, 12 patients with complex intracranial aneurysms were treated with combined operative and endovascular methods. Seven patients demonstrated subarachnoid hemorrhage (two of Grade II, two of Grade III, and three of Grade IV). Five patients demonstrated unruptured aneurysms, i.e., three giant aneurysms (one vertebrobasilar junction aneurysm, one middle cerebral artery bifurcation aneurysm, and one internal carotid artery-ophthalmic artery aneurysm), one large internal carotid artery-ophthalmic artery aneurysm, and one middle cerebral artery serpentine aneurysm. Management strategies involved either surgery followed by endovascular therapy (S-E; n = 5) or endovascular therapy followed by surgery (E-S; n = 7). S-E paradigms included aneurysm exploration followed by endovascular treatment (S-E1; n = 3), partial aneurysm clipping followed by endovascular aneurysm packing (S-E2; n = 1), and extracranial-to-intracranial bypass followed by endovascular parent vessel occlusion (S-E3; n = 1). E-S paradigms included superselective angiography followed by surgical clipping (E-S1; n = 2), Guglielmi detachable coil partial dome packing followed by delayed surgical clipping (E-S2; n = 2), proximal temporary vessel balloon occlusion followed by aneurysm clipping (E-S3; n = 2), and proximal permanent vessel occlusion followed by surgical aneurysm decompression for mass effect treatment (E-S4; n = 1). RESULTS: Eleven aneurysms (92%) were completely eliminated. The remaining aneurysm was 90% obliterated and remained quiescent at the 34-month follow-up examination, despite presenting with subarachnoid hemorrhage. No patient experienced repeat bleeding (follow-up period, 23+/-28 mo). There were no deaths. One patient achieved a fair outcome (Glasgow Outcome Scale score of III); all other patients experienced excellent outcomes (Glasgow Outcome Scale score of I). In all cases, the aneurysm management paradigm chosen had a positive effect on definitive therapy. CONCLUSION: Several factors can contribute to the complexity of intracranial aneurysms. Management strategies that combine operative and endovascular techniques in a complementary way, for the best possible outcomes for these patients, can be designed accordingly. 相似文献
43.
J Kelly R Wolin M Connolly A Afonso L James P Kirshmeier WR Bishop AT McPhail 《Canadian Metallurgical Quarterly》1998,6(6):673-686
Blocking farnesylation of oncogenic Ras proteins is a mechanism based therapeutic approach that is of current interest for the development of antitumor agents to treat ras associated tumors. As part of a SAR study on the lead farnesyl protein transferase (FPT) inhibitor I, we report here the synthesis of novel geometric isomers II and III and the FPT inhibition activity of their N-acyl and N-sulfonamido derivatives 15-65. The N-acyl derivatives are markedly less active than the lead inhibitor I thereby demonstrating that the spatial location of the N-acyl group in I is critical for binding of the compound to FPT. In contrast to I, the N-sulfonamido-II series is a novel lead of non-sulfhydryl, nonpeptidic compounds that are dual FPT/GGPT inhibitors. In light of recent reports on the alternative prenylation of N- and K-Ras, dual FPT/GGPT inhibitors may be required to control cell proliferation in tumors containing activated Ras. 相似文献
44.
JL Fraser S Raza K Chorny JL Connolly SJ Schnitt 《Canadian Metallurgical Quarterly》1998,22(12):1521-1527
OBJECTIVE: To examine the effect of treatment with an inactivated, gp120-depleted, HIV-1 immunogen (Remune) in 30 Thai subjects infected with HIV-1 subtype E. DESIGN: Sixty-week open-label study. METHODS: Thirty HIV-positive volunteers with CD4 cell counts > or = 300 x 10(6)/l were given intramuscular injections of Remune into the triceps muscle on day 1 and then at weeks 4, 8, 12, 24, 36, 48 and 60. RESULTS: Treatment with Remune was well-tolerated and augmented HIV-1-specific immune responses. Furthermore, subjects had a significant increase in CD4 cell count (P < 0.0001), CD4 cell percentage (P < 0.0001), CD8 cell percentage (P < 0.0001), and body weight (P < 0.0001) compared with pretreatment levels. Fourteen subjects with detectable viral load at day 1 showed a decrease at week 60 (P=0.04). Retrospective Western blot analysis showed 23 subjects with increased intensity of antibody bands and 15 patients showed development of new reactivities to HIV proteins, especially towards p17 and p15. CONCLUSION: These results indicate that HIV-specific immune-based therapeutic approaches such as Remune should be further examined in countries with different clades of HIV-1 and where access to antiviral drug therapies is limited. 相似文献
45.
JF Rebbeor GC Connolly ME Dumont N Ballatori 《Canadian Metallurgical Quarterly》1998,273(50):33449-33454
The transport systems involved in the export of cellular reduced glutathione (GSH) have not been identified, although recent studies implicate a role for some of the multidrug resistance associated proteins (MRP), including MRP1 and MRP2. The present study examined the hypothesis that the yeast orthologue of MRP, Ycf1p, mediates ATP-dependent GSH transport. [3H]GSH transport was measured in vacuolar membrane vesicles isolated from a control strain of Saccharomyces cerevisiae (DTY165), the isogenic DTY167 strain that lacks a functional Ycf1p, and in DTY167 transformed with a 2-micrometer plasmid vector containing YCF1. GSH transport in control vacuolar membrane vesicles was mediated largely by an ATP-dependent, low affinity pathway (Km = 15 +/- 4 mM). ATP-dependent [3H]GSH transport was cis-inhibited by substrates of the yeast Ycf1p transporter and inhibited by 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid, probenecid, and sulfinpyrazone, inhibitors of MRP1 and MRP2, but was minimally affected by membrane potential or pH gradient uncouplers. In contrast, ATP-dependent GSH transport was not seen in vacuolar membrane vesicles isolated from the DTY167 yeast strain without a functional Ycf1p but was restored to near wild-type levels in the DTY167 strain transformed with YCF1 and expressing the vacuolar Ycf1p transporter. On the other hand, expression and functional activity of a bile acid transporter, Bat1p, and of the V-type ATPase were similar in all three yeast strains. These results provide direct evidence for ATP-dependent low affinity transport of GSH by the yeast Ycf1p transporter. Because of the structural and functional homology between Ycf1p and MRP1 and MRP2, these data support the hypothesis that GSH efflux from mammalian cells is mediated by these membrane proteins. 相似文献
46.
This paper introduces the database programming language RAPP, which is an integration of the data type relation and relational algebraic operations with the modular multiprocessing language Pascal Plus. A portable version of the RAPP compiler has been implemented and is described. 相似文献
47.
This article describes the relationship between reading, phonological awareness abilities (PA), and intelligence in a group of 16 individuals with Williams syndrome (WS) and in a group of 16 typically developing children, matched for mental age. The individuals with WS were impaired in passage comprehension, in some areas of PA investigated (syllable deletion and rhyme detection), and in nonword reading accuracy, a measure of grapheme-phoneme conversion. This latter finding is relevant, considering that in Italy regular print-to-sound correspondence is the most practiced teaching routine in the early phases of learning to read. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
GrahamLSConnolly 《电子设计应用》2004,(11):104-106
近年来,开关产品纷纷进入PC、服务器、笔记本电脑和底座应用等领域,令许多芯片供应商推出各式总线开关产品。总线开关能够在板卡或器件插拔期间方便地隔离总线电容,通过隔离对数据(高速缓存和内存)进行多路复用,分解操作或进行电压变换。典型的总线开关设计为一个单独的NMOS器件,其缺点是:随着源电压接近Vcc,栅极的源-漏区被夹断,会限制电流的驱动能力和输出电压。 相似文献
49.
An examination of the role of design and operational parameters in a night ventilated library building located in Ireland, and which is subject to a maritime type climate, is considered. For this investigation, a self-contained space within the library building is analysed. A dynamic model of the space is created using the ESPr simulation package, which is compared with building data obtained from an experimental monitoring programme. Calculation of the mean bias deviation between the predicted and experimental data indicates agreement better than 0.45 °C for the dry bulb temperature and 1.1 °C for the mean radiant temperature. Using ESPr predictions, the role of different building design and operational parameters are examined by means of parametric analysis including building mass, ventilation duration, internal gain and ventilation rates. Compared to a reference base of the existing building, increasing the building mass was found to achieve a significant reduction in internal dry resultant temperatures, with a decrease of between 2 and 3 °C observed when mass was increased from 800 kg/m2 to 1600 kg/m2. Reducing building internal gains from 40 W/m2 to 20 W/m2 was observed to have the potential of further reducing dry resultant temperatures by up to 1 °C. Examination of night ventilation rates indicated that increasing night ventilation up to 10 ACH was observed to have a significant affect on reduction of dry resultant temperature, but further increases of air changes were observed to have a negligible effect. 相似文献
50.