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31.
"Ondol" is a Korean unique heating system. It is a specific radiant floor heating system using combustion heat of briquette or timber in Korea. Such traditional "Ondol" is changed to radiant heating system with pipe-coil embedded in the floor or slab. This study has contributed to the understandings of the transient behaviours of Ondol-heated floor panels and enclosure exposed to this type of heating system. The result is that the water supply temperature had a large effect on the rate of increase in floor surface and room air temperature. But, in spite of a higher water supply temperature, the heat flow rate was not increased considerably. The shallow pipe embedding depths, of course, result in a low heat flow rate.  相似文献   
32.
Ten axenic isolates of Trichomonas vaginalis were subcutaneously injected to the BALB/c mice in order to assess their pathogenicity by means of so-called "mouse assay" method. All the isolates revealed neutral and acid proteinase activities both in their lysates and in culture media, but the specific activities of both proteinases in the severely pathogenic group were significantly higher than the mildly pathogenic group (p < 0.05). In the SDS-PAGE system in which the electrophoretic gels contained 0.4% gelatin as the substrate, five different banding patterns of trichomonal proteinases were detected, and the patterns were closely related with the pathogenicity of the isolates of T. vaginalis. All five bands might be regarded as cysteine proteinases group in the inhibitor assays. The cytotoxicity of the lysates of T. vaginalis to the target Chinese hamster ovarian (CHO) cell line was also significantly different according to the pathogenicity of the isolates, and generally lower in the lysates treated with cysteine proteinase inhibitors than in the control lysates. In summarizing the results, it might be considered that the proteinases of T. vaginalis showing five electrophoretic banding patterns are closely related with the pathogenicity and cytotoxicity of the isolates of T. vaginalis.  相似文献   
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The relative incidence of accidental injury for Navy enlisted men during 1974-1977 was analyzed for 68 occupations, three pay grade or job responsibility levels, and duty status (on or off duty) at the time of the injury. Thirteen "blue-collar", predominantly sea-going or construction occupations, were significantly higher than the Navy injury rate norm and 26 "white-collar" occupations, typically in clerical, supply, administrative or technical specialties, were significantly lower than the Navy norm. An inverse linear relationship was found between injury rate and job responsibility for all occupations combined. This relationship varied by occupation, however, suggesting that experience and familiarity with the work environment may not moderate risks to the same degree in all occupational fields. Occupations with high on-duty injury rates tended to have high off-duty rates as well, suggesting at least some common causal factors.  相似文献   
35.
We introduce a novel transmission-line method for determining the penetration depth in thin high-temperature superconducting (HTS) films. The method is based on the accurate measurement of the inductance per unit length of a superconducting coplanar-waveguide (CPW) transmission line fabricated on the HTS sample. Using the experimentally obtained inductance per unit length, we interpolate the penetration depth from a table of numerically determined values of inductance (per unit length) as a function of penetration depth, calculated from a coupled transmission-line model. A novelty of our procedure is the utilization of the multiline thru-reflect-line (TRL) method and the calibration-comparison method to accurately determine the inductance per unit length of the superconducting transmission line. By measuring different CPW geometries patterned onto the same thin-film sample, we can verify our penetration depth values. We demonstrate this technique by extracting the penetration depth for several different HTS films at 76 K. Estimated uncertainties in the extracted penetration depth are also provided. Contribution of an agency of the US government not subject to copyright.  相似文献   
36.
Supersaturated designs are factorial designs in which the number of factors exceeds the number of observations. Satterthwaite has suggested constructing such designs by a randomization procedure (random balance designs). In the present paper systematic designs are constructed which are, in a certain sense, m nearly orthogonal M possible. Examples of such designs are given constructed on an electronic computer and some properties of the designs are discussed.  相似文献   
37.
ABSTRACT

Internet voice and video calling have demonstrated a dramatic rise in quality in the past several years and have quickly become communication technologies with a disruptive impact on society. Librarians, who regularly adopt such technologies in outreach and public services, should evaluate Web-calling programs as potential sources of innovative reference programming. This article describes the development of Skype video and Internet telephony pilot reference services at the Ohio University Libraries and considers the utility of Skype and VoIP in a library setting.  相似文献   
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Prolinx,® Inc. of Bothell, WA has developed the RapXtract™ 384 Dye Terminator Removal Kit for full automation of DNA sequencing reaction purification. The RapXtract product line is based upon proprietary superparamagnetic particle technology that eliminates the need for centrifugation, vacuum filtration, or modified primers to achieve purification of sequencing reactions. The kit described here is pre-dispensed in a 384-well microtiter plate and run on the TECAN GENESIS Workstation 150 (Tecan U.S. Inc., Research Triangle Park, NC). This system enables rapid purification of up to 384 sequencing reactions in a single run.As the completion of the Human Genome Project nears, it is imperative for biotechnology and pharmaceutical companies to increase throughput of DNA sequencing in order to be competitive in the drug discovery and validation process. The “race to market” requires a shift from standard DNA sequencing processes-including DNA sequencing reaction purification-towards complete walk-away automation for all steps.Existing sequencing reaction purification methods (Table 1) require considerable resources including: plastic and other laboratory consumables; specialized equipment, such as high-speed centrifuges or vacuum filtration apparatus; and labor-intensive protocols requiring large amounts of technician time. As a result, walk-away automation of standard purification methods is difficult and expensive.  相似文献   
40.
The authors assert that L. B. Smith and L. Samuelson's (2006; see record 2006-20488-029) most recent critique of A. E. Booth, S. R. Waxman, and Y. T. Huang's (2005; see record 2005-05098-004) work missed its mark, deflecting attention from the important theoretical difference between the two sets of authors' positions and focusing instead on imagined differences and minor expositional complaints. The authors' goal in this response is twofold. First, they aim to redirect attention to the 1 clear difference between the 2 theoretical positions regarding word learning, a difference that is focused on the role of conceptual (in conjunction with perceptual) information in word learning. Second, they place L. B. Smith and L. Samuelson's (2006) current critique in the context of previous exchanges. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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