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41.
Mary Karlsson Antti Lakka Kristiina Sulankivi Awad S. Hanna Benjamin P. Thompson 《Canadian Metallurgical Quarterly》2008,134(4):289-299
The use of the Internet, e-mail, and other technologies has been steadily filtering into the building process, creating a concurrent engineering (CE) environment, and enabling collaborative efforts in the building process. The concurrent engineering environment is established by a variety of tools, including internet accessible servers, e-mail, mobile telephones, and many other existing CE tools. Organizations involved in the construction process recognize the need for assessment of benefits resulting from CE tools, but find the evaluation of these benefits difficult and complicated. The project presented in this paper, “project management and organization in the concurrent engineering environment (ProCE),” is applicable to both researchers and practitioners. The ProCE project developed a measuring model, which may be used by future researchers in this area, attempted to measure benefits derived from using the CE environment in construction design and project management routines, and developed guidelines for best practice implementation by practitioners, based on four case studies. The project included the measurement of both the quantitative and qualitative benefit of CE environment implementation in building construction projects using tools that were readily available through application service providers. Measurement of cost and other quantifiable benefits have been extensively studied. Therefore, the majority of the discussion in the current paper will address the ProCE project’s measurement of qualitative benefits. 相似文献
42.
We have developed a one-step, homogeneous noncompetitive immunoassay for small analytes using recombinant antibodies and morphine as the model analyte. A highly specific antibody against the immune complex (IC) formed between an anti-morphine antibody and morphine was selected from a naive scFv phage display library. The in vitro phage library selection procedure avoids the difficulties associated with the production of anti-IC antibodies by animal immunization. The anti-morphine and the anti-IC antibodies were labeled with a pair of fluorescence resonance energy transfer (FRET) fluorophores. In the FRET assay the labeled antibodies were incubated with saliva samples spiked with morphine, codeine, or heroin. Within 2 min, 5 ng/mL morphine, which is clearly under the recommended cutoff level, was detected without cross-reactivity to codeine or heroin. This assay principle is also widely applicable to other small analytes. 相似文献
43.
Magdalena Markowicz-Piasecka Karol Sadowski Johanna Huttunen Joanna Sikora Kristiina M. Huttunen 《International journal of molecular sciences》2021,22(11)
Metformin, apart from its glucose-lowering properties, has also been found to demonstrate anti-cancer properties. Anti-cancer efficacy of metformin depends on its uptake in cancer cells, which is mediated by plasma membrane monoamine transporters (PMAT) and organic cation transporters (OCTs). This study presents an analysis of transporter mediated cellular uptake of ten sulfonamide-based derivatives of metformin in two breast cancer cell lines (MCF-7 and MDA-MB-231). Effects of these compounds on cancer cell growth inhibition were also determined. All examined sulfonamide-based analogues of metformin were characterized by greater cellular uptake in both MCF-7 and MDA-MB-231 cells, and stronger cytotoxic properties than those of metformin. Effective intracellular transport of the examined compounds in MCF-7 cells was accompanied by high cytotoxic activity. For instance, compound 2 with meta-methyl group in the benzene ring inhibited MCF-7 growth at micromolar range (IC50 = 87.7 ± 1.18 µmol/L). Further studies showed that cytotoxicity of sulfonamide-based derivatives of metformin partially results from their ability to induce apoptosis in MCF-7 and MDA-MB-231 cells and arrest cell cycle in the G0/G1 phase. In addition, these compounds were found to inhibit cellular migration in wound healing assay. Importantly, the tested biguanides are more effective in MCF-7 cells at relatively lower concentrations than in MDA-MB-231 cells, which proves that the effectiveness of transporter-mediated accumulation in MCF-7 cells is related to biological effects, including MCF-7 cell growth inhibition, apoptosis induction and cell cycle arrest. In summary, this study supports the hypothesis that effective transporter-mediated cellular uptake of a chemical molecule determines its cytotoxic properties. These results warrant a further investigation of biguanides as putative anti-cancer agents. 相似文献
44.
We studied the effects of plasticizer and cellulose nanowhisker content on the dispersion and properties of cellulose acetate butyrate (CAB)‐based bionanocomposites. The cellulose nanowhiskers in an aqueous medium were solvent‐exchanged to nonaqueous polar solvent (acetone) and used for nanocomposite processing by solution casting. The plasticized and unplasticized nanocomposites with 5 and 10 wt % cellulose nanowhisker content were prepared. Atomic force microscopy indicated nanoscale dispersion of whiskers in the CAB matrix. The dynamic mechanical analysis showed an increase in storage modulus with addition of cellulose nanowhiskers, especially above the glassy‐rubbery transition region. Thermogravimetric analysis showed an improvement in thermal stability with increased whisker content for both unplasticized and plasticized nanocomposites. The plasticized nanocomposites showed better transparency than the unplasticized composites, indicating a better dispersion of cellulose nanowhiskers in CAB, in the presence of a plasticizer. The dynamic mechanical properties and thermal stability increased, whereas transparency decreased with increased CNW content. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
45.
Hanne Heikkinen Piia Jallinoja Samuli I Saarni Kristiina Patja 《Nicotine & tobacco research》2008,10(7):1199-1207
The objective of the study was to examine the association between overall and health-related quality of life and smoking in men and women of discrete smoking groups in Finland. The design was a Health 2000 Survey, conducted in Finland 2000--2001. The setting and participants were a two-stage, stratified, nationally representative cluster sample that comprised 8,028 persons aged 30 or over living in mainland Finland. Health-related quality of life was measured by the 15D questionnaire; and overall quality of life was assessed by a single question measure capturing the respondent's own perception and estimation of his/her quality of life. The present study showed that daily smokers had both lower health-related and overall quality of life than never-smokers among the Finnish adult population. Health-related quality of life profiles showed that daily smokers did worse than never-smokers in a considerable number of the health dimensions. The effects of smoking were observed not only through health: the daily smokers registered significantly lower ratings of overall quality of life compared with never-smokers, too. Both the health-related and overall quality of life of ex-smokers approached those of never-smokers. The results of the present study suggest that improved health is not the only benefit of smoking cessation; better quality of life and more fulfilling everyday living can also be expected. As the major health consequences of smoking usually manifest themselves only after several years of smoking, both health-related and overall quality of life measurements could be used as an intervention tool for motivating people to quit. 相似文献
46.
Challenges for wood‐thermoplastic composites to be utilized in structural applications are to lower product weight and to improve the long‐term load performance. Silane crosslinking of the composites is one way to reduce the creep during long‐term loading and to improve the mechanical properties. In this study, silane crosslinked wood‐polyethylene composites were produced by reactive extrusion and subsequently manufactured into rectangular profiles. The silane crosslinked composites were stored in a sauna at 90 °C to increase the degree of crosslinking. The toughness of the silane crosslinked composites was significantly higher than for the non‐crosslinked composites. Improved adhesion between the wood and polyethylene phases is most likely the reason for the improved toughness of the crosslinked composites. There was no significant difference in flexural modulus between the crosslinked and non‐crosslinked composites. In addition, impact testing showed that the impact strength of the crosslinked composites was considerable higher (at least double) than the non‐crosslinked. The effect of temperature on the impact strength of the composites indicated slightly higher impact strength at −30 °C than at 0° and at 25 °C, and then an incrase in impact strength at 60 °C. Crosslinking also reduced the creep response during short‐term loading. Moreover, scanning electron microscopy on the fracture surface of the crosslinked composites revealed good adhesion between the polyethylene and wood phases. POLYM. COMPOS. 27:184–194, 2006. © 2006 Society of Plastics Engineers 相似文献
47.
Kristiina Laine Tiina Belt Lauri Rautkari James Ramsay Callum A. S. Hill Mark Hughes 《Journal of Materials Science》2013,48(24):8530-8538
The purpose of this study was to analyse the fundamental phenomena related to the swelling behaviour of densified and thermally modified wood under changing moisture content, as well as to investigate the differences in recovery behaviour between four different methods: (i) soaking–drying cycles, (ii) soaking–drying cycles in hot water, (iii) water-soaking with continuous data logging to measure dynamic changes in thickness and (iv) humid–dry cycles at different relative humidity (RH). Methods were applied to untreated, thermally modified, densified (D) and densified + thermally modified (DTM) Scots pine sap wood samples. Soaking methods were found to produce significantly higher set-recovery results than RH cycling, with higher temperature accelerating the relaxation during soaking. Repeated cycles increased the swelling of the densified samples. The RH thresholds for set-recovery were found to be between 65 and 75 % for the D samples and between 75 and 84 % in the case of DTM samples. 相似文献
48.
This article investigates the transport behavior of three aromatic organic solvents, viz. benzene, toluene, and p‐xylene in natural rubber nanocomposite membranes containing cellulose nanofibres (CNFs) and cellulose nanowhiskers (CNWs) isolated from bamboo pulp. The solvent molecules act as molecular probes to study the diffusion, sorption, and permeation through the nanocomposites, and provide information on the nanocomposite structure and matrix–filler interactions. Both the nanocelluloses were found to decrease the uptake of aromatic solvents in nanocomposite membranes, but the effect was more significant in the case on nanofibers compared to nanowhiskers. Furthermore, the uptake decreased with increased penetrant size; being the highest for benzene and the lowest for p‐xylene. Transport parameters such as diffusion coefficient, sorption coefficient, and permeation coefficient have been calculated. Comparison of the experimental values of equilibrium solvent uptake with the predicted values indicated that both the nanocelluloses have restricted the molecular mobility at the interphase and thereby decreased the transport of solvents through the materials; being more significant for nanofibers. The results showed that both the used cellulosic nanomaterials act as functional additives capable of manipulating and tailoring the transport of organic solvents through elastomeric membranes, even at concentrations as low as 2.5 wt %. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
49.
Regenerated cellulose fibers as impact modifier in long jute fiber reinforced polypropylene composites: Effect on mechanical properties,morphology, and fiber breakage
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Polypropylene/jute fiber (PP‐J) composites with various concentrations of viscose fibers (VF) as impact modifiers and maleated polypropylene (MAPP) as a compatibilizer have been studied. The composite materials were manufactured using direct long fiber thermoplastic (D‐LFT) extrusion and compression molding. The effect of fiber length, after the extrusion process, on composites mechanical performance and toughness was investigated. The results showed that the incorporation of soft and tough VF on the PP‐J improved the energy absorption of the composites. The higher impact strength was found with the addition of 10 wt % of the impact modifier, but the increased concentration of the impact modifier affected the tensile and flexural properties negatively. Similarly, HDT values were reduced with addition of viscose fibers whereas the addition of 2 wt % of maleated polypropylene significantly improved the overall composite properties. The microscopic analysis clearly demonstrated longer fiber pullouts on the optimized impact modified composite. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41301. 相似文献
50.
Kristiina Jokinen 《Universal Access in the Information Society》2006,4(4):374-392
This article describes the User Model component of AthosMail, a speech-based interactive e-mail application developed in the context of the EU project DUMAS. The focus is on the system’s adaptive capabilities and user expertise modelling, exemplified through the User Model parameters dealing with initiative and explicitness of the system responses. The purpose of the conducted research was to investigate how the users could interact with a system in a more natural way, and the two aspects that mainly influence the system’s interaction capabilities, and thus the naturalness of the dialogue as a whole, are considered to be the dialogue control and the amount of information provided to the user. The User Model produces recommendations of the system’s appropriate reaction depending on the user’s observed competence level, monitored and computed on the basis of the user’s interaction with the system. The article also discusses methods for the evaluation of adaptive user models and presents results from the AthosMail evaluation.The research was done while the author was affiliated with the University of Art and Design Helsinki as the scientific coordinator of the DUMAS project. 相似文献