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101.
Golden-Kreutz Deanna M.; Thornton Lisa M.; Wells-Di Gregorio Sharla; Frierson Georita M.; Jim Heather S.; Carpenter Kristen M.; Shelby Rebecca A.; Andersen Barbara L. 《Canadian Metallurgical Quarterly》2005,24(3):288
The authors investigated the relationship between stress at initial cancer diagnosis and treatment and subsequent quality of life (QoL). Women (n = 112) randomized to the assessment-only arm of a clinical trial were initially assessed after breast cancer diagnosis and surgery and then reassessed at 4 months (during adjuvant treatment) and 12 months (postadjuvant treatment). There were 3 types of stress measured: number of stressful life events (K. A. Matthews et al., 1997), cancer-related traumatic stress symptoms (M. J. Horowitz, N. Wilner, & W. Alvarez, 1979), and perceived global stress (S. Cohen, T. Kamarck, & R. Mermelstein, 1983). Using hierarchical multiple regressions, the authors found that stress predicted both psychological and physical QoL (J. E. Ware, K. K. Snow, & M. Kosinski, 2000) at the follow-ups (all ps 相似文献
102.
Most network applications assume continuous connectivity-an assumption that does not “migrate” to wireless environments. The authors present the design of a communication layer for mobile computing that dynamically adapts to changes in network connections. Our work was part of AMIGOS (Advanced Mobile Integration in General Operating Systems), a collaboration between researchers at the University of Copenhagen in Denmark and the University of Minho in Portugal. The AMIGOS project provides transparent support for semi connected operations on mobile computers running a standard operating system; the project home page is at http://www.econ.cbs.dk/people/birger/AMIGOS/. Briefly, our design lets a mobile user connect a mobile host to a LAN, then disconnect the host from it. The user then can reconnect, for example, via a Global System for Mobile Communications (GSM) cellular modem without losing TCP/IP connections. We want to allow existing TCP/IP based applications to be used in a mobile environment, without application modifications 相似文献
103.
Outi E. Mäkinen Reetta Kivelä Laura Nyström Mogens L. Andersen Tuula Sontag-Strohm 《Food chemistry》2012
The aim of this study was to determine the role of the formation of radicals and hydrogen peroxide in the viscosity loss of beta-glucan extracts from oat and barley. Radicals derived from endogenous H2O2 were formed spontaneously in all extracts. The decomposition of H2O2 by catalase had little or no effect on the viscosity, and the radical formation detected and measured by electron spin resonance (ESR) spectroscopy did not predict the shelf life of crude beta-glucan extracts. The addition of FeSO4 accelerated the radical formation and viscosity loss, revealing the sensitivity of the extract viscosity towards catalysts for oxidation. Using 50% cadoxen in the extracts slowed down the viscosity loss in all extracts but still led to a 10–70% decrease of the initial viscosities during 4 weeks of storage. The results suggest that the viscosity loss may be a result from multiple mechanisms including chemical reactions during storage as well as aggregation and conformational changes. 相似文献
104.
Serban N. Stamatin Maryam Borghei Shuang Ma Andersen Sune Veltze Virginia Ruiz Esko Kauppinen Eivind M. Skou 《International Journal of Hydrogen Energy》2014
Commercially available graphitized carbon nanofibers and multi-walled carbon nanotubes, two carbon materials with very different structure, have been functionalized in a nitric–sulfuric acid mixture. Further on, the materials have been platinized by a microwave assisted polyol method. The relative degree of graphitization has been estimated by means of Raman spectroscopy and X-ray diffraction while the relative concentration of oxygen containing groups has been estimated by X-ray photoelectron spectroscopy, which resulted in a graphitic character trend: Pt/GNF > Pt/F-GNF ? Pt/MWCNT > Pt/F-MWCNT. Transmission electron microscopy showed that the Pt particle size is around 3 nm for all samples, which was similar to the crystallite size obtained by X-ray diffraction. The activity towards electrochemical reduction of oxygen has been quantified using the thin-film rotating disk electrode, which has shown that all the samples have a better activity than the commercially available electrocatalysts. The trend obtained for the graphitic character maintained for the electrochemical activity, while the reverse trend has been obtained for the accelerated ageing test. Long-term potential cycling has demonstrated that the functionalization improves the stability for multi-walled carbon nanotubes, at the cost of decreased activity. 相似文献
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Dr. techn. Dr. tekn. h.c. Prof. Emeritus J?rgen Bach Andersen M.Sc. Ph.D. Prof. Gert Fr?lund Pedersen 《e & i Elektrotechnik und Informationstechnik》2012,129(6):383-386
In future mobile communications many antennas will coexist on the device. This creates a number of problems related to bandwidth, efficiency, and correlation. Remedies are discussed in the paper, and attention is called to the promising area of adaptive matching, which also can solve problems related to the user. 相似文献
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G. C. Morrison H. V. Andersen L. Gunnarsen D. Varol E. Uhde B. Kolarik 《Indoor air》2018,28(1):188-197
Polychlorinated biphenyl (PCB) contamination of buildings continues to pose an exposure threat, even decades after their application in the form of calks and other building materials. In this research, we investigate the ability of clothing to sorb PCBs from contaminated air and thereby influence exposure. The equilibrium concentration of PCB‐28 and PCB‐52 was quantified for nine used clothing fabrics exposed for 56 days to air in a Danish apartment contaminated with PCBs. Fabric materials included pure materials such as cotton and polyester, or blends of polyester, cotton, viscose/rayon, and/or elastane. Air concentrations were fairly stable over the experimental period, with PCB‐28 ranging from 350 to 430 ng/m3 and PCB‐52 ranging from 460 to 550 ng/m3. Mass accumulated in fabric ranged from below detection limits to 4.5 mg/g of fabric. Cotton or materials containing elastane sorbed more than polyester materials on a mass basis. Mass‐normalized partition coefficients above detection limits ranged from 105.7 to 107.0 L/kg. Clothing acts as a reservoir for PCBs that extends dermal exposure, even when outside or in uncontaminated buildings. 相似文献