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12.
Shirin Elahi 《Information Security Technical Report》2009,14(3):113-118
In today's digital era no one has knowledge, access or control of all their available personal information. This makes the very concepts of privacy and consent increasingly illusory and raises questions that are likely to shape not only the future form of cyberspace, but also the political, social and economic interactions within it. The institutions tasked with regulation of the physical world are ill equipped to respond and undertake a similar role in the virtual world; the timescales, dimensions and scope are all materially different. This article sets out five dilemmas that will need to be addressed in the search for solutions. 相似文献
13.
The present study proposes new conditions for achieving the aged-look effect of denim. Indigo dyed cotton fabrics were treated by corona discharge at different power levels and number of passages. Colorimetric parameters of corona treatment were assessed by the CIE L*a*b* colorimetric system and the pH and colour fastness of samples were tested. The surfaces of dyed samples were studied by scanning electron microscopy and Fourier Transform–infrared/attenuated total reflectance (FTIR/ATR) analysis. Under the same conditions of corona treatment, the faded-look effect was reduced as the depth of dyeing was increased. Increasing the power and the number of passages increases L* and b * and decreases a * values. This indicates that samples become lighter and yellower but soaping can reduce yellowness. FTIR/ATR results show that indigo dye oxidises, and isatin and anthranilic acid are produced. The pH levels of corona-treated samples reduce as the power and number of passages increase. This acidification is in agreement with the results of FTIR/ATR analysis. 相似文献
14.
Shirin M. Giffin William J. Wadsworth Iain T. McKinnie Anthony D. Woolhouse Gerald J. Smith Tim G. Haskell 《Journal of Modern Optics》2013,60(14):1941-1945
Abstract We report an investigation of the laser beam quality, efficiency and photostability of rhodamine 590 solid state dye lasers with hosts based upon 2-hydroxyethylmethacrylate and methylmethacrylate P(HEMA:MMA) co-polymers and modified methylmethacrylate (MPMMA) polymers with ethanol and dimethylsulphoxide additives. Highest efficiencies were obtained with MPMMA, with slope efficiencies of up to 44% (corresponding to 61% optical-optical conversion) measured for ethanolic MPMMA. P(HEMA:MMA) hosts gave superior photostability, with the highest normalized photostability of 240 GJ mol?1 obtained for a P(HEMA:MMA) 1:1 rod. A simple resonator has been used to compensate the effects of thermal lensing and pump mode-mismatch, resulting in optimized beam quality for MPMMA lasers. 相似文献
15.
Sulfonated anthracenedione dyes are medium priority organic compounds targeted for environmental assessment under the Government of Canada's Chemical Management Plan (CMP). Since organic compounds undergo transformations in environmental matrices, understanding these transformations is critical for a proper assessment of their environmental fate. In the current study, we used zero-valent iron (ZVI) to provide insight into reductive transformation processes available to the anthracenedione dye, Acid Blue 129 (AB 129), a dye which is used in the textile industry. At high temperatures, we found that AB 129 was rapidly reduced (within 3 h) after being adsorbed onto the ZVI-surface, whereupon decomposition took place via multiple competitive and consecutive reaction pathways. Reaction products were identified using state-of-the-art accurate mass Liquid Chromatography-Quadrupole Time of Flight-Mass Spectroscopy (LC-QToF-MS). Five transformation products were identified, including a genotoxic (and thus, potentially carcinogenic) end-product, 2,4,6-trimethylaniline. The same products were found at room temperature, demonstrating that the transformation pathways revealed here could plausibly arise from biological and/or environmental reductions of AB 129. Our results demonstrate the importance of identifying reaction product arising from priority substances as part of the environmental risk assessment process. 相似文献
16.
ER Polosukhina SV Kuznetsov NP Logcheva TN Zabotina MR Tenuta AD Shirin GI Kaletin AG Turkina NV Tsvetaeva IuV Shishkin ZG Kadagidze ND Khoroshko MA Volkova AIu Baryshnikov 《Canadian Metallurgical Quarterly》1998,70(7):21-25
AIM: The expression of CD95(Fas/APO-1) antigen was studied on bone marrow cells of 19 MDS patients, peripheral blood blast cells of 15 acute myeloid leukemia (AML) patients, blast cells and granulocytes of 68 patients with chronic myeloid leukemia (CML)--24 in chronic, 9 in accelerated phase and 35 in blastic crisis (BC)--by indirect surface immunofluorescence assay using flow cytometry (FACScan, Becton Dickinson, USA). RESULTS: CD95(Fas/APO-1) antigen was revealed on bone marrow cells of 8 out of 19 (36.8%) MDS patients; the percentage of antigen-positive cells was 38.1 +/- 19.2%; on 45.5 +/- 22.8% of cells in 6(45%) of 15 AML patients. Fas/APO-1 antigen was totally absent in CML chronic stage; its expression was found in 34% (12 of 35) of our patients with CML BC on peripheral blood blasts and in 56% (5 of 9) on peripheral blast cells of CML patients in acceleration phase. CONCLUSION: The data on overall survival of CD95-positive MDS patients suggest that the presence of Fas antigen is a favorable prognostic sign for patients with MDS. The patients from CD95-negative group represent a risk group both for survival and AML transformation. In CML BC group the survival does not depend upon Fas-antigen expression. 相似文献
17.
Abrahamson David; Schludermann Shirin; Schludermann Eduard 《Canadian Metallurgical Quarterly》1973,41(2):320
Employed 120 male and 113 female undergraduates in a replication of H. L. Mirels's (see record 1970-10386-001) study which found 2 factors in analyzing responses to 23 items on Rotter's Internal-External Control Scale. The same polar dimensions of "luck" as the arbiter of life events as opposed to personal control were found as well as a 2nd dimension of degree of control over political and social institutions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
18.
In this study, the effects of different parameters on the morphological properties of ternary blends were investigated. Therefore two systems (PET/H‐EVA/PP and PET/L ‐EVA/PP, H‐EVA and L ‐EVA are high and low viscosity, respectively) were prepared by melt mixing process. In all of the blends, poly (ethylene terephthalate) (PET) as the major phase‐ with poly propylene (PP) and two grades of poly (ethyl‐stat‐vinylacetate) (EVA) with different viscosities and subsequently different interfacial interactions was blended. Theoretical models predicted positive spreading coefficient for two grades of EVA and lower free energy for the samples consisting of EVA and PP as the shell and the core phases respectively. With changing core shell ratio, droplet size of samples containing L ‐EVA and H‐EVA increased and decreased, respectively. Subinclusion of shell into the core was observed in some blended samples. In systems containing H‐EVA, by thickening the shell phase; multi core morphology was observed which would be related to the coalescence phenomenon inter the droplets. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
19.
Tarahomjoo S Katakura Y Satoh E Shioya S 《Journal of Bioscience and Bioengineering》2008,105(2):116-121
With the aim of constructing an efficient protein display system for lactic acid bacteria (LABs), the effect of fusion direction on the cell-surface binding activity of the C-terminal region of the peptidoglycan hydrolase (CPH) of Lactococcus lactis IL1403 was studied. CPH fused to the alpha-amylase (AMY) of Streptococcus bovis 148 either at its C-terminus (CPH-AMY) or at its N-terminus (AMY-CPH) was expressed intracellularly in Escherichia coli. This domain was able to direct binding of AMY to the surface of L. lactis ATCC 19435 in both constructs. However, the number of bound molecules per cell and the specific activity for starch digestion in the case of CPH-AMY were 3 and 14 times greater than those in the case of AMY-CPH, respectively. Of the LABs tested, L. lactis ATCC 19435 showed the highest binding capability for CPH-AMY, up to 6 x 10(4) molecules per cell, with a dissociation rate constant of 5.00 x 10(-5) s(-1). The binding of CPH-AMY to the surface of Lactobacillus delbrueckii ATCC 9649 cells was very stable with a dissociation rate constant of 6.96 x 10(-6) s(-1). The production of CPH-AMY in the soluble form increased 3-fold as a result of coexpression with a molecular chaperone, trigger factor. The results of this study suggest the usefulness of CPH as a bidirectional anchor protein for the production of cell-surface adhesive enzymes in E. coli. Furthermore, the importance of the fusion direction of CPH in determining cell-surface binding and enzymatic activities was shown. 相似文献
20.
The C-terminal region of the peptidoglycan hydrolase (CPH) of Lactococcus lactis IL1403 fused to the linker region and the starch-binding domain (SBD) of the *-amylase of Streptococcus bovis 148 was produced intracellularly in Escherichia coli. The fusion protein (CPH-SBD) was able to bind to the cell surface of Lactobacillus casei NRRL B-441 and to corn starch. Therefore, adhesion of cells to corn starch was mediated by the fusion protein. At a cell density of 10(9) cfu/ml and a starch concentration of 5 mg/ml, CPH-SBD-displaying L. casei cells aggregated with corn starch, whereas the free cells of L. casei did not form any aggregates with corn starch. After incubation in simulated gastric juice (pH 3.0, 1 h), the survival percentages of free cells, amylose-coated free cells, and free cells mixed with corn starch were 0.074%, 7.2%, and 3.1% respectively. When CPH-SBD-displaying bacteria aggregated with corn starch, their survival percentage was 8% higher than that of free cells mixed with corn starch. The survival of the amylose-coated CPH-SBD-displaying L. casei cells was comparable to that of amylose-coated free cells, whereas the survival percentage of amylose-coated aggregates of CPH-SBD-displaying bacteria with corn starch was 28% higher than that of amylose-coated mixture of free cells with corn starch. These results demonstrate the potential usefulness of the cell-surface display technique for enhancement of the delivery of viable microorganisms to the intestinal tract. 相似文献