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1.
Anne Toppinen Miska Sauru Satu Pätäri Katja Lähtinen Anni Tuppura 《Construction Management & Economics》2019,37(4):201-216
In transitioning to a renewable material-based bio economy, growing public and industry interest is apparent for using wooden multistory construction (WMC) as a sustainable urban housing solution in Europe, but its business implications are not well understood. In our study, we evaluate, which internal and external factors of competitiveness are shaping the future of WMC, especially in the context of Finland and Sweden. Based on a multi-level perspective of socio-technical transitions, we conducted a three-stage dissensus-based Delphi study. The identified internal and external factors affecting the future competitiveness of the WMC business emphasize the importance of skilled architects and builders and the role of standardized building systems. Based on our results, the key aspects influencing the future competitiveness of WMC in the region are related to the development of technical infrastructure and project-based business networks, while additional changes in regulatory framework are perceived as less important. We conclude that towards 2030, the strong cognitive rules founded in the concrete-based building culture in these countries is likely to inhibit the dynamics of the socio-technical regime level. A change is also needed in the WMC business culture towards more open cross-sectoral collaboration and new business networks between different-sized players. 相似文献
2.
Radio frequency (RF) induction heating is used in order to generate thermal waves in conducting materials. This technique is applied to measure the thickness of tungsten-carbide plasma coating on stainless-steel plates. The letter briefly discusses major advantages and disadvantages of RF induction heating. 相似文献
3.
Drought Stress Alters the Concentration of Wood Terpenoids in Scots Pine and Norway Spruce Seedlings 总被引:10,自引:0,他引:10
Drought is known to have an impact on the resistance of conifers to various pests, for example, by affecting resin flow in trees. Little is known, however, about the quantitative and qualitative changes in resin when trees are growing in low moisture conditions. We exposed Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seedlings to medium and severe drought stress for two growing seasons and analyzed the monoterpenes and resin acids in the main stem wood after two years of treatment. In addition to secondary chemistry, we measured the level of nutrients in the needles and the growth response of seedlings. After the first year of treatment, drought stress did not affect the growth of seedlings, but in the second year, shoot growth was retarded, especially in Scots pine. In both conifer species, severe drought increased the concentrations of several individual monoterpenes and resin acids. Total monoterpenes and resin acids were 39 and 32% higher in severe drought-treated Scots pine seedlings than in the controls, and 35 and 45% higher in Norway spruce seedlings. In Scots pine needles, the concentrations of nitrogen and phosphorus increased, while magnesium and calcium decreased compared to controls. In Norway spruce needles, nutrient concentrations were not affected. The results suggest that drought stress substantially affects both the growth of conifers and the chemical quality of the wood. We discuss the potential trade-off in growth and defense of small conifer seedlings. 相似文献
4.
Satu Pitkäaho Satu Ojala Toni Kinnunen Reijo Silvonen Riitta L. Keiski 《Topics in Catalysis》2011,54(16-18):1257-1265
Development of a reliable laboratory scale test for the design of industrial catalysts is crucial. In this article, different laboratory-scale tests were compared with an industrial scale CVOCs treatment. With dichloromethane (DCM) the laboratory scale test results corresponded well to the industrial scale oxidation results. However, the perchloroethylene (PCE) conversions measured in industry were always higher than what was achieved in the laboratory scale indicating that the industrial scale catalytic incinerator operating in transient conditions is highly beneficial in PCE oxidation. It was clearly shown that in order to design high-quality laboratory scale experiments, information on complete composition and total concentration of the emission is needed but also different types of catalytic tests need to be used depending on the industrial reactor. In addition, the catalysts’ performance in an industrial VOC abatement unit was examined as the oxidation efficiencies of DCM, PCE and other hydrocarbons (OHC) were compared after 3, 10 and 23 months of operation. After 23 months and 13,065 operating hours, no significant decrease in the activity of the catalysts was observed showing that the used noble metal catalysts are highly resistant towards these demanding conditions. 相似文献
5.
Projection onto convex sets has recently been suggested as an approach to time-varying image compression. In this paper, an image coding technique based on such an approach is developed. In particular, pixel and frequency domain information is combined in order to improve image quality over standard transform coding at given bit rates. The use of nonintersecting convex sets is shown to be optimum for two sets and a given error measure. Convex sets and projections are discussed in general and then in the context of image compression. Simulation results are presented for single frame images as well as for image sequences. 相似文献
6.
La Carbona S Viitasalo-Frösen S Masson D Sassi J Pineau S Lehtiniemi M Corroler D 《The Science of the total environment》2010,409(2):247-255
Ship's ballast waters transport large numbers of organisms which may become invasive in coastal regions. One option to address this problem is the use of biocides as ballast water treatment (BWT). Efficacy and environmental acceptability of three commercial active substances (the BWT biocides Peraclean® Ocean and Seakleen®, and alkylamine-based biocide Mexel® 432/336) were tested against three bacteria species, two vegetative microalgae and one zooplanktonic larva, in 10 and 30 Practical Salinity Unit (PSU) waters. In both salinities, PeraClean® Ocean was the most effective biocide against bacteria causing > 90% mortality at 20 mg/l, compared with 50 mg/l for Mexel® 432/336 and > 500 mg/l for Seakleen®. Regarding zooplankton, Seakleen® was the most effective chemical causing 90% mortality in 24 h at concentrations < 6 mg/l (LC9024 h) in both salinities, compared with 23 and 26 mg/l for Mexel® 432/336 and 370 and 480 mg/l for PeraClean® Ocean in 10 and 30 PSU, respectively. Similar pattern of efficacy was obtained for microalgae in 30 PSU: effective concentrations inducing 50% growth inhibition in 4 days were ≤ 1.6 mg/l for Seakleen®, ≤ 10.1 mg/l for Mexel® 432/336 and ≤ 30.9 mg/l for PeraClean® Ocean. Our work highlighted that treated waters displayed residual toxicity after 24 h still inducing mortality depending on the organism and biocide. However Mexel® 432/336 is the only biocide which had no impact on oyster larvae development at effective concentration. Altogether our data showed that Mexel® 432/336 was the only biocide displaying a broad spectrum efficacy in concentrations < 50 mg/l and not toxic for oyster larvae development at this concentration. However residual toxicity of treated waters for any organism should be taken into account in BWT systems utilising biocides. 相似文献
7.
Xiang Jim; Srivamadan Maheswaran; Rajala Raju; Jia Zongchao 《Protein engineering, design & selection : PEDS》2000,13(5):339-344
A B72.3 Fab/sTn2 complex was modeled from the known structureof B72.3 Fab and the dimeric Tn-serine cluster (sTn2). In thecomplex model, the side chains of 15 heavy- and light-chaincomplementarity-determining region (CDR) residues and the mainchains of two light-chain CDR residues contact the sTn2 epitope.Among 15 CDR residues which contact sTn2 in the model, two heavy-chainresidues (Ser95 and Tyr97) and light-chain CDR residue (Tyr96)have been confirmed in a previous study. To test the accuracyof the computational model, further site-directed mutagenesiswas performed by alanine scanning on the remaining 12 residuesthat are predicted in the model to have side-chain interactionswith sTn2. Of these 12 mutants, eight that are all from theheavy-chain (His32Ala, Ala33Leu, Tyr50Ala, Ser52Ala, Asn52Ala,Asp56Ala, Lys58Ala and Tyr96Ala) had significantly reduced sTn2affinities, and four consisting of three light-chain mutations(Asn32Ala, Trp92Ala and Thr94Ala) and one heavy-chain mutation(His35Ala) retained wild-type sTn2 affinity. On the whole, thisevidence suggests that the complex model, although not perfect,is correct in many of its features. In a more general vein,these results lend credibility to the computational modelingapproach for the study of the molecular basis of antigenantibodycomplexes. 相似文献
8.
H Yki-J?rvinen L Ryysy M Kauppila E Kujansuu J Lahti T Marjanen L Niskanen S Rajala S Salo P Sepp?l? T Tulokas J Viikari MR Taskinen 《Canadian Metallurgical Quarterly》1997,82(12):4037-4043
An initial improvement in glycemic control is often followed by gradual deterioration of glycemia during insulin treatment of patients with noninsulin-dependent diabetes mellitus (NIDDM). We examined the causes of such worsening in a 12-month follow-up analysis of 100 insulin-treated NIDDM patients in the Finnish Multicenter Insulin Therapy Study who were treated with either combination therapy with insulin or insulin alone. In the entire study group, glycemic control averaged 9.7 +/- 0.2% at 0 months and 8.0 +/- 0.1%, 8.0 +/- 0.1%, 8.2 +/- 0.1%, and 8.5 +/- 0.2% at 3, 6, 9, and 12 months (P < 0.001 for each time point vs. 0 months). Glycemic control at 12 months was significantly worse than that at 3 (P < 0.001), 6 (P < 0.001), and 9 months (P < 0.02). Baseline body mass index was the most significant predictor of deterioration in glycemic control. During 1 yr, hemoglobin A1c decreased almost 3-fold more (by 1.7 +/- 0.2%; P < 0.001 vs. 0 months) in patients whose baseline weight was below the mean baseline body mass index of 28.1 kg/m2 (nonobese patients) than in those whose weight exceeded 28.1 kg/m2 (obese patients; 0.5 +/- 0.2%; P = NS vs. 0 months; P < 0.01 vs. obese patients). Glycemic control improved similarly over 1 yr in the nonobese subjects and deteriorated similarly in the obese patients regardless of their treatment regimen. Insulin doses, per body weight, were similar in the nonobese and obese patients. The nonobese patients consistently gained less weight during 12 months of combination therapy with insulin (3.5 +/- 0.6 kg at 12 months) than during insulin therapy alone (5.1 +/- 0.6 kg; P < 0.05). The treatment regimen did not influence weight gain in the obese group, who gained 4.4 +/- 1.0 kg during combination therapy with insulin and 4.5 +/- 1.1 kg during insulin therapy alone. We reached the following conclusions: 1) after an initial good response, glycemic control deteriorates more in obese than in nonobese patients with NIDDM; 2) in obese patients, weight gain per se cannot explain the poor glycemic response to combination or insulin therapy, but it may induce a disproportionately large increase in insulin requirements because of greater insulin resistance in the obese than in the nonobese; 3) in nonobese patients, glycemic control improves equally during 1 yr with combination therapy with insulin and insulin alone, but combination therapy with insulin is associated with less weight gain than treatment with insulin alone; 4) weight gain appears harmful, as it is associated with increases in blood pressure and low density lipoprotein cholesterol. 相似文献
9.
I R?ih? J Kaprio M Koskenvuo T Rajala L Sourander 《Canadian Metallurgical Quarterly》1998,65(5):785-787
The aim of this study was to examine the contribution of environmental factors to the pathogenesis of Alzheimer's disease by comparing environmental differences in twin pairs discordant for Alzheimer's disease. Seventy four twin pairs discordant for Alzheimer's disease were found by linking the Finnish twin cohort and the Hospital Discharge Register from years 1972-91. In 50 pairs (25 monozygotic and 25 dizygotic pairs), both co-twins had responded to a questionnaire survey in 1975. Exposure differences were compared between these pairs. A reduced risk of Alzheimer's disease was significantly associated with a higher level of schooling (relative risk 0.3; 95% confidence interval 0.1-0.9, p=0.029). In addition, a reduced risk was suggestively associated with ambidextrousness or left handedness (p=0.083) and an increased risk with marriage (p=0.052), widowhood (p=0.074), and a history of cholelithiasis (p=0.071). In conclusion, a reduced risk of Alzheimer's disease was associated with a higher level of schooling. 相似文献
10.
Gun Wirtanen Satu Salo Merja Karwoski Anna-Maija Sjöberg 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1995,200(3):194-197
A microbiological screening method for the detection of irradiation of frozen poultry meat was developed on the basis of the combined use of total cell count by the direct epifluorescent filter technique (DEFT) and viable cell count by the aerobic plate count method (APC). Samples of ground, deboned poultry leg were irradiated or not with dose levels of 3, 5 and 7 kGy using an electron beam accelerator. All samples were frozen before the irradiation treatment. The average values of the differences between DEFT and APC counts in control samples and those irradiated with doses of 3, 5 and 7 kGy were 1.14 log units for control samples, and 3.16, 3.68 and 3.79 log units for the irradiated samples. A difference of at least 2 log units can therefore be considered as a limit value indicating probable irradiation treatment necessitating further investigations.
Anwendung eines mikrobiologischen Unterscheidungsverfahrens zum Nachweis der Bestrahlung von gefrorenem Hühnerfleisch
Zusammenfassung Es wurde ein mikrobiologisches Verfahren zum Nachweis der Bestrahlung von tiefgefrorenem Hühnerfleisch auf der Basis kombinierten Einsatzes direkter Epifluoreszenzfiltertechnik (DEFT) und Kolonieauszählung (APC) entwickelt. Die Proben - knochenfreie, zerkleinerte Hühnerschenkel - waren entweder unbestrahlt oder mit einem Elektronenbeschleuninger mit Dosen von 3, 5 bzw. 7 kGy bestrahlt worden. Alle Proben waren vor der Bestrahlung eingefroren worden. Die Mittelwerte der Differenzen zwischen den DEFT- und den APC-Ergebnissen betrugen bei den unbestrahlten Proben 1,14 logarithmische Einheiten und bei den mit 3, 5 bzw. 7 kGy bestrahlten Proben 3,16, 3,68 bzw. 3,79 logarithmische Einheiten. Die Differenz von wenigstens zwei logarithmischen Einheiten kann als Grenze für die Möglichkeit eines Nachweises eventueller Bestrahlung betrachtet werden und macht weitere Untersuchungen erforderlich.相似文献