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1.
C. Pronk 《Software》1992,22(10):885-897
During standardization discussions on Modula-2 the question was raised whether the future standard should need a clause stating a set of minimal requirements for conforming implementations regarding the ‘structuredness’ of lexical, syntactical and run-time constructs in programs written in this language. It was decided to test a number of compilers to find their actual limits on the structuredness of some of these constructs. The test results do not only show these limits, but the inability of some compilers to handle large and complex inputs is shown as well.  相似文献   
2.
Pilot tests were performed with a process combination of electrodialysis and ozonation for the removal of micropollutants and the concentration of nutrients in urine. In continuous and batch experiments, maximum concentration factors up to 3.5 and 4.1 were obtained, respectively. The desalination capacity did not decrease significantly during continuous operation periods of several weeks. Membrane cleaning after 195 days resulted in approximately 35% increase in desalination rate. The Yeast Estrogen Screen (YES), a bioassay that selectively detects oestrogenic compounds, confirmed that about 90% of the oestrogenic activity was removed by electrodialysis. HPLC analysis showed that ibuprofen was removed to a high extent, while other micropollutants were below the detection limit. In view of the fact that ibuprofen is among the most rapidly transported micropollutants in electrodialysis processes, this result indicates that electrodialysis provides an effective barrier for micropollutants. Standardised plant growth tests were performed in the field with the salt solution resulting from the treatment by electrodialysis and subsequent ozonation. The results show that the plant height is comparable to synthetic fertilisers, but the crop yield is slightly lower. The latter is probably caused by volatilisation losses during field application, which can be prevented by improved application technologies.  相似文献   
3.
BACKGROUND: Both fibroblast-mediated cytokine gene therapy and bone marrow transplantation (BMT) have proven to be efficient protocols for the recovery of bone marrow depression. In this report, the effects of fibroblast-mediated interleukin (IL)-6 gene therapy, in combination with BMT, on the recovery of irradiation-induced bone marrow depression were investigated. METHODS: NIH3T3 fibroblast cells engineered to secrete IL-6 (NIH3T3-IL-6) or NIH3T3 cells transduced with the neomycin gene (NIH3T3-Neo), in combination with 10(7), 10(6), or 10(5) syngeneic bone marrow cells, were implanted into irradiated mice. RESULTS: The platelets and white blood cells in the peripheral blood of the irradiated mice increased greatly 12 days after implantation of NIH3T3-IL-6 cells and BMT, the white blood cell counts were restored to a normal level 32 days after the combined therapy, and the platelet number was obviously higher than that in mice implanted with NIH3T3-Neo and BMT. Twenty and 25 days after the combined therapy, the mice showed accelerated recovery of colony-forming unit (CFU)-granulocyte/macrophages and CFU-megakaryocytes when compared with the mice implanted with NIH3T3-Neo cells and BMT. Ten days after lethal irradiation with gamma rays, the spleens formed more CFU-spleen in mice implanted with NIH3T3-IL-6 cells and BMT than in mice injected with phosphate-buffered saline or NIH3T3-Neo cells. Combined therapy with NIH3T3-IL-6 cell implantation and BMT delayed the survival period of the hematopoietic-depressed mice significantly when compared with therapy with NIH3T3-Neo cell implantation and BMT. CONCLUSIONS: These data demonstrated that the combined therapy of fibroblast-mediated IL-6 gene therapy and BMT could significantly promote the recovery of irradiation-induced hematopoietic depression.  相似文献   
4.
The fatigue property of an asphalt mix is an important issue in pavement design. This property is often determined with the aid of a four-point bending (4PB) test in controlled deflection mode. The fatigue property is related to the decrease in the calculated complex stiffness modulus, however, due to the non- homogenous stress and strain field in the beam, the measured response does not represent the stiffness modulus of the material but a weighted stiffness value. For a correct interpretation, a fatigue damage material model like the Asphalt Concrete Pavement-Fatigue model is needed. After integration, the calculated and measured responses are compared. By varying the model parameters, an excellent comparison between the two responses is obtained up to a certain number of cycles. This number of cycles is denoted as the fatigue life N PH . The accumulated dissipated energy at the surface of the beam in the midsection can be expressed as a constant times the fatigue life N PH to the power z and also as a constant times the product of the fatigue life N PH and the initial dissipated energy in the first cycle. Using these two findings, a Wöhler curve was established similar to the one directly based on the strain amplitudes and fatigue life data.  相似文献   
5.
Fatigue of bituminous mixtures   总被引:1,自引:0,他引:1  
This paper presents an interlaboratory test campaign organized by the RILEM 182-PEB Technical Committee. In the campaign, 11 different test methods, comprising uniaxial tension/compression, 2-, 3- and 4-point bending and indirecttension tests, were utilized in order to investigate fatigue characteristics of a dense graded asphalt concrete mixture. The testing conditions specified were sinusoidal excitation at 10Hz and 10°C using controlled strain and stress modes. In total, more than 150 fatigue tests were carried out during the investigation. The fatigue test results were analyzed using both classical as well as continuum damage mechanics approaches. The fatigue test results obtained using the classical fatigue approach are considerably influenced by test type and mode of loading (controlled stress or strain) used. Consequently, this approach has limited use in realistic fatigue characterization of bituminous materials and pavement structures. In contrast to the classical approach, models founded on continuum damage theory may serve to isolate intrinsic fatigue characteristics from the influence of so-called biased effects, which are largely caused by the accelerated laboratory testing. The continuum damage models investigated may constitute steps, towards a rational mechanistic fatigue characterization model, which are important for effective future pavement design.  相似文献   
6.
The process of elicitation and synthesis of the collective understanding of a cultural domain held by a group of stakeholders is challenging. This problem typifies the pre-project activity from which a coherent understanding of the benefits sought from infrastructure investment must emerge to inform the business case rationale. The anthropological freelisting method is evaluated as a solution by determining its ability to be operationalized in a practical form for project application. Using data from the stakeholders of a large NHS Scotland building project, the use of multidimensional scaling for data analysis is compared with participatory pilesorting to determine which freelisting protocol balances insight with practicality. Neither approach is found to offer an ideal method of characterizing sought benefits. The social construction of pilesorting promotes reliability while the analytical rigour of multidimensional scaling remains attractive to auditors. Their distinct insights suggest that both approaches should be combined in future and used alongside further post-elicitation devices from anthropology such as cultural consensus modelling or structured conceptualization.  相似文献   
7.
In the present research, we examined why some people have more difficulty than others in staying faithful to their romantic partners. Three studies supported our main prediction that executive control is associated with romantically involved individuals' ability to stay faithful. Study 1 showed that participants with a higher level of executive control reported less difficulty in staying faithful to their partners than did those with lower levels of executive control. In Study 2, romantically involved male participants were placed in a waiting room together with an attractive female confederate. Results showed that participants with a higher level of executive control showed less flirting behavior with the confederate than did those with lower levels of executive control. Study 3 demonstrated that a higher level of executive control was related to a lower expressed desire to meet an attractive other, but only for romantically involved participants. Together, these studies showed that executive control helps romantically involved individuals to deal with the lure of attractive alternatives. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
8.
PURPOSE: Fluid retention, which includes peripheral edema, ascites, pleural or pericardial effusion, or a combination of these that is sometimes associated with significant weight gain, is one of the most troublesome cumulative side effects of docetaxel. A suggestive observation from the data base available at the manufacturer (Rhone-Poulenc Rorer) was that patients who received venotonic drugs appeared to tolerate more courses of docetaxel. This prompted a comparative study to investigate whether the venotonic drug hydroxyethylrutosiden could reduce or delay docetaxel-related fluid retention. METHODS: A total of 85 patients with metastatic breast cancer who were treated with docetaxel at a dose of 100 mg/m2 with corticoid comedication were allocated to receive either 300 mg hydroxyethylrutosiden given orally four times daily (group A) or no hydroxyethylrutosiden (group B). The end point for analysis was the development of fluid retention of > or = grade 2. RESULTS: Fluid retention of > or = grade 2 was reported in 14 of 42 patients (33%) in group A and in 15 of 43 patients (35%) in group B and occurred after a median of 4 cycles of docetaxel in both groups. Weight gain was similar in groups A and B. CONCLUSION: We conclude that hydroxyethylrutosiden does not reduce or delay the incidence and severity of docetaxel-related fluid retention.  相似文献   
9.
The removal of natural organic matter (NOM) using nanofiltration (NF) is increasingly becoming an option for drinking water treatment. Low molecular weight (LMW) organic compounds are nevertheless only partially retained by such membranes. Bacterial regrowth and biofilm formation in the drinking water distribution system is favoured by the presence of such compounds, which in this context are considered as the assimilable organic carbon (AOC). In this study, the question of whether NF produces microbiologically stable water was addressed. Two NF membranes (cut-off of about 300 Da) were tested with different natural and synthetic water samples in a cross-flow filtration unit. NOM was characterised by liquid chromatography with organic carbon detection (LC-OCD) using a size-exclusion column in addition to specific organic acid measurements, while AOC was measured in a batch growth bioassay.Similarly to high molecular weight organic compounds like polysaccharides or humic substances that have a permeability lower than 1%, charged LMW organic compounds were efficiently retained by the NF membranes tested and showed a permeability lower than 3%. However, LMW neutrals and hydrophobic organic compounds permeate to a higher extent through the membranes and have a permeability of up to 6% and 12%, respectively. Furthermore, AOC was poorly retained by NF and the apparent AOC concentration measured in the permeated water was above the proposed limit for microbiologically stable water. This indicates that the drinking water produced by NF might be biologically unstable in the distribution system. Nevertheless, in comparison with the raw water, NF significantly reduced the AOC concentration.  相似文献   
10.
Alkyl glycosides are interesting intermediates for the production of biodegradable surfactants. Synthesis of ethyl beta-d-fructofuranoside by invertase-catalysed ethanolysis of sucrose has been extensively reported in literature. However, this procedure yields mixtures of glucose, fructose, sucrose and ethyl beta-d-fructofuranoside. Purification of ethyl beta-d-fructofuranoside from such mixtures by chromatographic methods is laborious, difficult to scale up and requires organic solvents. The yeast Hansenula polymorpha grows rapidly on glucose, fructose and sucrose. Sucrose hydrolysis in this yeast is catalysed by an intracellular alpha-glucosidase ('maltase'); consequently, H. polymorpha should be unable to hydrolyse ethyl beta-d-fructofuranoside. Indeed, aerobic cultivation of H. polymorpha on sugar mixtures obtained by invertase-catalysed ethanolysis of sucrose resulted in the complete removal of contaminating sugars, leaving ethyl beta-d-fructofuranoside as the sole organic compound in culture supernatants. Pure ethyl beta-d-fructofuranoside was recovered from the supernatants by mixed-bed ion exchange chromatography with an 86% yield.  相似文献   
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