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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   
3.
A reproducible wafer‐scale method to obtain 3D nanostructures is investigated. This method, called corner lithography, explores the conformal deposition and the subsequent timed isotropic etching of a thin film in a 3D shaped silicon template. The technique leaves a residue of the thin film in sharp concave corners which can be used as structural material or as an inversion mask in subsequent steps. The potential of corner lithography is studied by fabrication of functional 3D microfluidic components, in particular i) novel tips containing nano‐apertures at or near the apex for AFM‐based liquid deposition devices, and ii) a novel particle or cell trapping device using an array of nanowire frames. The use of these arrays of nanowire cages for capturing single primary bovine chondrocytes by a droplet seeding method is successfully demonstrated, and changes in phenotype are observed over time, while retaining them in a well‐defined pattern and 3D microenvironment in a flat array.  相似文献   
4.
Objective: Low-cost (e.g., computer-tailored) interventions with sustained effects are needed to increase and maintain physical activity in older adults. This study examined the long-term efficacy of 2 computer-tailored physical activity interventions for older adults and its psychosocial and environmental mediators. Methods: A clustered randomized controlled trial (N = 1,971) was conducted that included 3 research arms: (a) basic computer-tailored print intervention, targeting psychosocial mediators; (b) environmentally computer-tailored print intervention, targeting psychosocial and environmental mediators; and (c) no-intervention control group. Interventions were developed using the intervention mapping approach and consisted of 3 computer-tailored letters delivered over 4 months. Questionnaires assessed the study outcomes (i.e., total weekly days and total weekly minutes of physical activity) at baseline and 12 months. Potential mediators (i.e., awareness, attitude, self-efficacy, intention, social influence, intrinsic motivation, self-regulation, and perceived environment) were assessed at baseline and at 3 or 6 months. Results: Multilevel regression analyses revealed that both interventions significantly changed total weekly days of physical activity compared with the control group, but only the environmentally computer-tailored print intervention significantly changed weekly minutes of physical activity. Multiple mediation models showed that the effects of both interventions on weekly days of physical activity were mediated by changes in awareness and intention. Conclusions: Computer-tailored interventions were effective in inducing long-term behavioral changes in physical activity behavior of older adults. Awareness and intention were found to be important mediators of changing daily physical activity and should be included in future computer-tailored intervention studies. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
5.
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   
6.
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   
7.
Sequence of the CDC10 region at chromosome III of Saccharomyces cerevisiae   总被引:2,自引:0,他引:2  
A 4.74 kb DNA fragment from the right arm of chromosome III of Saccharomyces cerevisiae, adjacent to the centromere region was sequenced. Four open reading frames with an ATG initiation codon and larger than 200 bp were found in this fragment. The largest open reading frame of 966 bp was identified as the CDC10 gene.  相似文献   
8.
We present a new nucleic acid lateral flow immunoassay (NALFIA) for the assessment of listeria contamination. The detection procedure starts with enrichment of sample in Half Fraser broth (24 h). Following isolation of DNA, a duplex PCR is performed with two labelled primer sets, one generic and directed to a specific sequence of the gene encoding 16S rRNA from Listeria spp. and the other specific and directed to a part of the prfA gene encoding the central virulence gene regulator from the food pathogen Listeria monocytogenes (3.5 h). The PCR solution is directly added to the one-step assay device and the appearance of a grey/black line is indicative of the presence of specific amplicons (max 15 min). In all tests performed, the method correctly identified L. monocytogenes and strains of Listeria spp. PCR material of over 20 food samples was tested by NALFIA. The method proved to be useful for the detection of L. monocytogenes in different kinds of food samples.  相似文献   
9.
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   
10.
The authors investigated autobiographical memory specificity in subjects who formerly had depression. In 122 euthymic patients with at least two previous major depressive episodes, memory specificity was significantly impaired compared to matched control participants but not related to residual symptoms and illness characteristics, was not differentially affected by cognitive therapy, and was also not predictive of relapse/recurrence during the 2-year follow-up. However, memory specificity was associated with age, education, and immediate and delayed memory recall. The results suggest that memory specificity may reflect a global cognitive impairment that remains in patients who (formerly) had depression but does not constitute a trait marker for vulnerability for relapse/recurrence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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