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排序方式: 共有126条查询结果,搜索用时 15 毫秒
1.
Kati Huttunen Eeva Kauhanen Asko Vepsäläinen Anne Hyvärinen 《The Science of the total environment》2010,408(11):2305-2311
Moisture and mold problems in buildings contaminate also the furniture and other movable property. If cleaning of the contaminated furniture is neglected, it may continue to cause problems to the occupants even after the moisture-damage repairs. The aim of this study was to determine the effectiveness of high-efficiency ozone treatment in cleaning of the furniture from moisture-damaged buildings. In addition, the effectiveness of two cleaning methods was compared. Samples were vacuumed from the padded areas before and after the treatment. The microbial flora and concentrations in the dust sample were determined by quantitative cultivation and QPCR-methods. The immunotoxic potential of the dust samples was analyzed by measuring effects on cell viability and production of inflammatory mediators in vitro. Concentrations of viable microbes decreased significantly in most of the samples after cleaning. Cleaning with combined steam wash and ozonisation was more effective method than ozonising alone, but the difference was not statistically significant. Detection of fungal species with PCR showed a slight but nonsignificant decrease in concentrations after the cleaning. The immunotoxic potential of the collected dust decreased significantly in most of the samples. However, in a small subgroup of samples, increased concentrations of microbes and immunotoxicological activity were detected. This study shows that a transportable cleaning unit with high-efficiency ozonising is in most cases effective in decreasing the concentrations of viable microbes and immunotoxicological activity of the furniture dust. However, the method does not destroy or remove all fungal material present in the dust, as detected with QPCR analysis, and in some cases the cleaning procedure may increase the microbial concentrations and immunotoxicity of the dust. 相似文献
2.
Steven C. Cermak Jakob W. Bredsguard Robert O. Dunn Travis Thompson Kati A. Feken Katie L. Roth James A. Kenar Terry A. Isbell Rex E. Murray 《Journal of the American Oil Chemists' Society》2014,91(12):2101-2109
A series of 26 different antioxidants and commercial antioxidant packages designed for petroleum‐based materials, containing both natural and synthetic‐based materials, were evaluated with dimeric coconut‐oleic estolide 2‐ethylhexyl ester (2‐EH), a bio‐based material. The different antioxidants were categorized into different classes of phenolic, aminic, and blended/others materials. The oxidation onset temperatures (OT) using non‐isothermal pressurized differential scanning calorimetry (PDSC) were measured and recorded under previously reported standard conditions. The aminic series gave the best resistance to oxidation as defined by the PDSC method with OT of 246.6 and 244.7 °C for the best two performers, which was a 38 °C improvement over the uninhibited or unformulated dimer estolide material. The phenolic series, containing most of the naturally occurring antioxidants, was the least successful formulation package for the dimer estolide. The blended/other materials, which were specifically designed for petroleum‐based lubricants, did not have the best OT, since the estolides and other bio‐based materials interact differently than their petroleum counterparts. A number of potential antioxidants have been identified as useful additives for the estolides esters. The OT of the estolide and formulated materials correlated well with other bio‐based materials such as biodiesel. 相似文献
3.
Christin Hengst Susanne Werner Lars Müller Kati Fröhlich Volker Böhm 《European Food Research and Technology》2009,230(2):249-254
The aim of the present analysis was to study the influence of the sample concentration on the measured antioxidant capacity, since such investigations are scarce but necessary to ensure the reproducibility of the results. Pure substances (ascorbic acid, gallic acid, Trolox®, uric acid) and food extracts (strawberry nectar, tomato extract, white tea) were analysed using seven common antioxidant capacity assays (three versions of Trolox equivalent antioxidant capacity, TEAC; ferric reducing antioxidant power, FRAP; photochemiluminescence, PCL; oxygen radical absorbance capacity, ORAC and total phenolics assay). For all applied pure substances and in most of the assays effects of the sample concentration on the measured antioxidant capacity were observed. Since it remains speculative how sample concentration does affect the measured antioxidant capacity exactly, it is strongly recommended to use at least three sample concentrations for analysis to detect and to discuss concentration-dependent effects. 相似文献
4.
Jaakko Saari Fatima Siddique Sanna Korpela Elina Mntyl Teemu O. Ihalainen Katri Kaukinen Katriina Aalto-Setl Katri Lindfors Kati Juuti-Uusitalo 《International journal of molecular sciences》2022,23(3)
The small intestinal epithelium has an important role in nutrition, but also in drug absorption and metabolism. There are a few two-dimensional (2D) patient-derived induced pluripotent stem cell (iPSC)-based intestinal models enabling easy evaluation of transcellular transport. It is known that animal-derived components induce variation in the experimental outcomes. Therefore, we aimed to refine the differentiation protocol by using animal-free components. More specifically, we compared maturation of 2D-cultured iPCSs toward small intestinal epithelial cells when cultured either with or without serum, and either on Geltrex or on animal-free, recombinant laminin-based substrata. Differentiation status was characterized by qPCR, immunofluorescence imaging, and functionality assays. Our data suggest that differentiation toward definitive endoderm is more efficient without serum. Both collagen- and recombinant laminin-based coating supported differentiation of definitive endoderm, posterior definitive endoderm, and small intestinal epithelial cells from iPS-cells equally well. Small intestinal epithelial cells differentiated on recombinant laminin exhibited slightly more enterocyte specific cellular functionality than cells differentiated on Geltrex. Our data suggest that functional small intestinal epithelial cells can be generated from iPSCs in serum-free method on xeno-free substrata. This method is easily converted to an entirely xeno-free method. 相似文献
5.
One of the most interesting and important properties of connectionist systems is their ability to control sophisticated manipulation robots, i.e. to produce a large number of efficient control commands in real-time. This paper represents an attempt to give a comprehensive report of the basic principles and concepts of connectionism in robotics, with an outline of a number of recent algorithms used in learning control of a manipulation robot. A major concern in this paper is the application of neural networks for off-line and on-line learning of kinematic and dynamic relations used in robot control at the executive hierarchical level. 相似文献
6.
Pesonen Anu-Katriina; R?ikk?nen Katri; Heinonen Kati; J?rvenp?? Anna-Liisa; Strandberg Timo E. 《Canadian Metallurgical Quarterly》2006,20(4):648
The actor-partner interdependence model was used to test whether one parent's depressive vulnerability (self-criticism and dependency) was associated with the same parent's own (an intraparental association) and the other parent's (a cross-parental association) ratings of their 5-year-old child's temperament (536 parents, 268 dyads). The more vulnerable the parents were, the more the children showed negative affectivity and lack of effortful control. Significant interactions with the parent's gender and between the spouses' depressive vulnerabilities were found, highlighting the fact that child outcomes are dependent on family processes. All associations were independent of maternal and paternal depressive symptoms. The influence of personality-based depressive traits on child temperamental outcomes and effective parenting is discussed with reference to between-dyad family dynamics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Ultralong 20 Milliseconds Charge Separation Lifetime for Photoilluminated Oligophenylenevinylene–Azafullerene Systems
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Georgios Rotas Kati Stranius Nikolai Tkachenko Nikos Tagmatarchis 《Advanced functional materials》2018,28(7)
The synthesis and characterization of oligophenylenevinylene (OPV)–azafullerene (C59N) systems in the form of OPV–C59N donor–acceptor dyad 1 and C59N–OPV–C59N acceptor–donor–acceptor triad 2 is accomplished. Photoinduced electronic interactions between OPV and C59N within 1 and 2 are assessed by UV–vis and photoluminescence. The redox properties of 1 and 2 are investigated, revealing a set of one‐electron oxidation and three one‐electron reduction processes owed to OPV and C59N, respectively. The electrochemical bandgap for 1 and 2 is calculated as 1.44 and 1.53 eV, respectively, and the free energy for the formation of the charge‐separated state for 1 and 2 via the singlet‐excited state of OPV is found negative, proving a thermodynamically favorable the process. Photoexcitation assays are performed in toluene and o‐dichlorobenzene (oDCB) and the reactions are monitored with time‐resolved absorption and emission spectroscopies. Competitive photoinduced energy and electron transfer are identified to occur in both systems, with the former being dominant in 2 . Markedly, the charge‐separated state in oDCB exhibits a much longer lifetime compared to that in toluene, reaching 20 ms for 1 , the highest ever reported value for fullerene‐based materials. These unprecedented results are rationalized by considering conformational phenomena affecting the charge‐separated state. 相似文献
8.
Hakala KS Laitinen L Kaukonen AM Hirvonen J Kostiainen R Kotiaho T 《Analytical chemistry》2003,75(21):5969-5977
Good reliability of Caco-2 permeability studies requires competent sampling and analytical methods to ensure the comparability of day-to-day experiments. In this work, two n-in-one LC/MS/MS methods based on two different ionization techniques were developed and validated for a group of reference compounds; eight of them are recommended by the Food and Drug Administration (FDA) for the evaluation of oral drug permeability. The performance of a new ionization technique, atmospheric pressure photoionization (APPI), as an interface for quantitative LC/MS analysis was evaluated in comparison to the electrospray ionization (ESI). Generally, the validation parameters, including sensitivity, accuracy, and repeatability, were comparable for the APPI and ESI methods. The main difference was that the linear quantitative range of APPI was 3-4 orders of magnitude (r(2) >/= 0.998) whereas in ESI it was typically 2-3 orders of magnitude (r(2) >/= 0.990). By the APPI and ESI methods, the simultaneous analysis of nine highly heterogeneous compounds was achieved within 5.5-7 min, which leads to significant savings in time and cost of the analyses. The successful validation data indicate the usefulness of both the methods for the rapid and sensitive (LOD values typically =5 nM) testing of drug transport across the Caco-2 monolayers, and after case-specific modification, the methods enable the permeability screening of new drug candidates. The applicability and reliability of both methods was demonstrated with a real batch of Caco-2 samples, each providing similar values of apparent permeability (P(app)). In addition, the individual permeabilities of the compounds in the cocktail experiments correlated closely to the ones obtained from single-compound experiments. 相似文献
9.
10.
V. Katić L. Ćurković M. Ujević Bošnjak S. Špalj 《Materialwissenschaft und Werkstofftechnik》2014,45(2):99-105
The goal of this study was to determine corrosion behavior of three orthodontic wires based on nickel‐titanium alloy (NiTi) in artificial saliva at temperature of 37 °C as function of immersion time. Following orthodontic wires were used: uncoated (NiTi), rhodium coated (Rh NiTi) and nitrified (N NiTi) orthodontic wires. Corrosion of investigated orthodontic wires were monitored by measuring of Ni2+ and Ti4+ ions released in artificial saliva by inductively coupled plasma‐optical emission spectroscopy (ICP‐OES) after 3, 7, 14, 21 and 28 days of immersion. Obtained results indicate that corrosion reaction of the NiTi wires in artificial saliva follows the parabolic rate law. According to the obtained values of parabolic corrosion rate constants, corrosion susceptibility of orthodontic wires decreases in the following order: Rh NiTi wire (Kp = 2.48 μg2/cm4 h) > NiTi wire (Kp = 1.6 × 10–3 μg2/cm4 h) > N NiTi wire (Kp = 6.0 × 10–4 μg2/cm4 h). These results indicate that in comparison with uncoated NiTi wire, rhodium coating significantly increases corrosion susceptibility, while nitrification effectively suppresses the release of Ni2+ and Ti4+ ions. 相似文献