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There is a widely believed myth that replacing the use of fossil fuels largely by renewable forms of energy is, with a possible exception of nuclear power, critically dependent on the development of appropriate new technologies. Accordingly, it is held that decarbonizing straight away is particularly difficult and expensive. There was a time when this idea had an element of reality, but this is no longer the case. Unfortunately, belief in this myth is shared by those in positions of influence. This paper serves to document that this presumed reality no longer holds, although the misconception may have been based on fact in the past. Whilst the survey of the available technology offered concentrates on electricity supply, it also documents that manufacture of synthetic fuels via hydrogen obtained by electrolysis of water and CO2 integrates smoothly with electricity grid stabilization as well as reducing the CO2 content of the atmosphere. The likely price and cost development in the energy market is also reviewed. In addition the role of CCS, in practice mainly capture from the air and industrial processes other than power generation is reviewed against the background of the cost effective generation of electricity by harvesting renewable forms of energy.  相似文献   
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Vaginismus is commonly described as a persistent difficulty in allowing vaginal entry of a penis or other object. Lifelong vaginismus occurs when a woman has never been able to have intercourse. A replicated single-case A-B-phase design was used to investigate the effectiveness of therapist-aided exposure for lifelong vaginismus. A baseline period (Phase A) was contrasted with exposure + follow-up (Phase B), using random switching between phases. The main outcome measure (intercourse ability) was assessed daily for 24 weeks. Ten women participated. The exposure consisted of a maximum of three 2-hr sessions during 1 week at a university hospital. The participant performed vaginal penetration exercises on herself, in the presence of a female therapist. Two follow-up sessions were scheduled over a 5-week period. Nine of the 10 participants reported having intercourse after treatment, and in 5 of the 9, intercourse was possible within the 1st week of treatment. The results remained at 1-year follow-up. Furthermore, exposure was successful in decreasing fear and negative penetration beliefs posttreatment and at 3-month and 1-year follow-ups. Therapist-aided exposure appears to be an effective treatment for lifelong vaginismus. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Architectural drawing systems are discussed, with emphasis on quality of user-interfaces and improvement offered by new computing technology. EdCAAD's STAG drawing system is described, demonstrating the benefits of newer technology.  相似文献   
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The degradability of starch from various feedstuffs was investigated in vitro by incubation of 500-mg amounts in 50 ml of a 3:1 rumen fluid/buffer solution at 39°C for 6 h. The rumen fluid was obtained from one of three cows fed on hay or hay and concentrate. The degree of degradation after 6 h incubation varied strongly for the 23 feedstuffs investigated. The degradation of starch from the same feedstuff in rumen fluid from a hay-fed cow was significantly lower than in rumen fluid from a concentrate-fed cow. It seemed that differences in degradability between feedstuffs were not determined by the ration of the donor cow, but merely by the properties of the starch. Processed feedstuffs showed a higher degradation of their starch than the unprocessed feedstuffs, independent of the ration of the donor cow. Particle size influenced degradation, but not of the starch of tapioca meal. A fairly constant ranking in degradability between the various feedstuffs was found. Fermentation of mixtures of feedstuffs showed about the same rate of degradation as found for the single products. Only when great differences in the degree of degradability existed was the degradation of the total starch enhanced. The time of collection of rumen fluid strongly influenced the in-vitro degradation of starch.  相似文献   
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BACKGROUND: Glomerular monocyte infiltration is an early feature of lipid-mediated renal injury in animal models. Interactions between mesangial and infiltrating mononuclear cells may contribute to the development of glomerular scarring. METHODS: Adherence of U-937 monocytes to low-density lipoprotein (LDL)- or tumor necrosis factor alpha (TNFalpha)-prestimulated human mesangial cells was assessed by colorimetry of nuclear staining with crystal violet. Blocking antibodies were added to examine the mechanisms of binding. Adhesion molecule expression and fibronectin synthesis were measured by ELISA. RESULTS: Preincubation of mesangial cells for 24 hours with LDL (100 micrograms/ml) or mildly oxidized (minimally modified) LDL (MM-LDL) increased monocyte adhesion by 207% and 240%, respectively, compared with control nonstimulated cells (100%). TNFalpha (100 U/ml) enhanced binding by 335% and up-regulated intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expression by 505% and 179%, respectively, as compared with MM-LDL (120% and 116%) and LDL, which had no effect. Blocking antibodies to these adhesion molecules inhibited monocyte binding to TNFalpha- and, to a lesser extent, MM-LDL-primed mesangial cells, but had no effect after LDL pretreatment. In contrast to TNFalpha, MM-LDL and LDL increased mesangial cell-associated fibronectin, whereas antibodies to fibronectin inhibited monocyte binding to lipoprotein-stimulated but not TNFalpha-stimulated cells. CONCLUSIONS: Although enhanced monocyte adhesion to TNFalpha- and, to a lesser extent, MM-LDL-stimulated mesangial cells is mediated by changes in ICAM-1 and VCAM-1 expression, both LDL and MM-LDL promote similar cellular interactions as a result of increased fibronectin production.  相似文献   
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Long-term memory impairment is often found in schizophrenia. The question remains whether this is caused by other cognitive deficits. One hundred eighteen first-episode patients were compared with 45 control participants on several memory tasks. The role of processing speed and central executive functions on memory performance was examined with regression analysis for all participants and for patients separately. Deficits were found in general verbal learning performance and retrieval in episodic memory and semantic memory. Processing speed reduced disease-related variance in all memory variables. Coordination, organization of information, and speed of processing were the best predictors for long-term memory deficits in patients. The amount of explained variance, however, is small, especially in general verbal learning performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The nucleotide sequence was determined of a 2·1 kb DNA fragment located at approximately 35 kb to the right of the centromere of chromosome VI from Saccharomyces cerevisiae. Analysis revealed the presence of a tRNAGLy gene, part of a delta element and a remarkable palindromic sequence. The longest open reading frame found encodes a putative protein of 195 amino acids. Although the fragment was isolated by hybridization to a human diacylglycerol kinase cDNA, no evidence was obtained for the presence of a gene encoding diacylglycerol kinase.  相似文献   
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The theorem of Huet and Lévy stating that for orthogonal rewrite systems (i) every reducible term contains a needed redex and (ii) repeated contraction of needed redexes results in a normal form if the term under consideration has a normal form, forms the basis of all results on optimal normalizing strategies for orthogonal rewrite systems. However, needed redexes are not computable in general. In the paper we show how the use of approximations and elementary tree automata techniques allows one to obtain decidable conditions in a simple and elegant way. Surprisingly, by avoiding complicated concepts like index and sequentiality we are able to cover much larger classes of rewrite systems. We also study modularity aspects of the classes in our hierarchy. It turns out that none of the classes is preserved under signature extension. By imposing various conditions we recover the preservation under signature extension. By imposing some more conditions we are able to strengthen the signature extension results to modularity for disjoint and constructor-sharing combinations.  相似文献   
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