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11.
Nephelometric turbidity is an optical index for the side scattering of light caused by fine particles suspended in water. When a mixed composition of suspended inorganic and organic materials, including dissolved organic material, is present, turbidity measurements can be affected by the different optical properties of the organic and inorganic materials present, and different turbidimeters are more or less sensitive to these influences. Two different methods of nephelometric turbidity measurement were assessed (using instruments confirming to two different turbidity standard methods: EPA 180.1 and ISO 7027). We investigated the influence of particulate organic matter and coloured dissolved organic matter on relationships between turbidity and suspended sediment concentration for rivers in diverse Otago catchments, in the South Island of New Zealand. The presence of organic matter and dissolved colour affected turbidity measurement owing to light absorption; however, turbidity measurement following the ISO 7027 standard, which specifies near infrared radiation at wavelengths where organic absorption is very weak, was less affected by organics. As a result, rating equations between suspended sediment and turbidity may be significantly different with ISO 7027 compared with EPA 180.1 methods.  相似文献   
12.
In this paper, we critically examine previous research on rating formats and rater training in the context of performance appraisal. Historically, the goal of this body of research has been to search for ways of maximizing the psychometric quality of performance evaluation data. Our central thesis is that there are a number of avenues for broadening this research. Accordingly, we propose a conceptual model that hopefully serves as a conceptual framework for future work in these 2 traditional performance appraisal research streams. For example, both rating formats and rater training research may be useful for facilitating and improving the feedback and employee development process, as well as reducing the potential existence of rater biases. In addition, format and training research may focus upon ways of enhancing both rater and ratee reactions to the appraisal system. A key feature of our model is the integration of national culture as a moderator of the relations between specific formats, training programs, and various outcomes. We consider both the national culture of raters and ratees, and focus specifically on comparisons between Western and East Asian cultures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
13.
Horton  R. 《Electronics letters》1976,12(15):386-387
The linearity of optical sources is a critical factor in analogue applications of optical fibres. The letter describes such considerations related to f.d.m. telephony, addressing both the l.e.d. and laser diode. From the information presented, conclusions are drawn on the viability of these applications.  相似文献   
14.
It has recently been noted that hemispherical structures have useful reflection characteristics. We describe a new application that makes use of these characteristics by controlling the reflectance of a surface composed of an array of hemispherical liquid droplets. In this system the reflectance state is spatially controlled through the use of electrowetting to alter the shape of an array of droplets. This may have an application in the field of electronic image displays.  相似文献   
15.
Evaluated C. E. Osgood and P. H. Tannenbaum's (see record 1955-08361-001) congruity model of attitude change, a regression model derived from the Osgood and Tannenbaum model, and D. R. Heise's (see record 1969-08323-001) 3 general linear models of attitude change, using data obtained from 208 undergraduates. 104 Ss rated 8 3-word (subject, verb, object) sentences 1st, and then rated the individual words. The other Ss rated the individual words 1st. The mean ratings for the 2 groups were compared to obtain the attitude change for each element, and the models were used to predict the change which resulted from the combination of the words into a sentence. Sex differences were found in mean attitudinal evaluations, and the inclusion of higher-order interaction terms increased the predictability of attitude ratings for females more than for males. Heise's Model III was the best predictor of attitude change, followed by his Model II and the regression model derived from the Osgood and Tannenbaum model. The Osgood and Tannenbaum model gave poor prediction of the mean attitudinal changes obtained. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
16.
Massive quantities of hazardous substances are transported each day throughout the United States. While most arrive safely at their destination, uncontrolled releases of substances in transit do occur and have the potential of causing acute public health consequences for those individuals at or near the release. Data from 16 state health departments participating in the Agency for Toxic Substances and Disease Registry's (ATSDR) Hazardous Substances Emergency Events Surveillance (HSEES) system were analyzed to determine the public health consequences that occurred from actual releases in transit. Of the 9392 transportation events analyzed, 9.1% resulted in 2008 victims, including 115 deaths. The population groups injured most often were employees and the general public. The most common injury sustained was respiratory irritation. Evacuations were ordered in 5.5% of events effecting at least 63,686 people. Human error and equipment failure were the most common factors leading to events. These findings underscore the importance of job safety training, community planning, and effective emergency response to prevent adverse public health consequences from occurring or lessen their effect on the public.  相似文献   
17.
18.
1. The pharmacological profile of adenosine A1 receptors in human, guinea-pig, rat and mouse brain membranes was characterized in a radioligand binding assay by use of the receptor selective antagonist, [3H]-8-cyclopentyl-1,3-dipropylxanthine ([3H]-DPCPX). 2. The affinity of [3H]-DPCPX binding sites in rat cortical and hippocampal membranes was similar. Binding site affinity was higher in rat cortical membranes than in membranes prepared from guinea-pig cortex and hippocampus, mouse cortex and human cortex. pKD values (M) were 9.55, 9.44, 8.85, 8.94, 8.67, 9.39 and 8.67, respectively. The binding site density (Bmax) was lower in rat cortical membranes than in guinea-pig or human cortical membranes. 3. The rank order of potency of seven adenosine receptor agonists was identical in each species. With the exception of 5'-N-ethylcarboxamidoadenosine (NECA), agonist affinity was 3.5-26.2 fold higher in rat cortical membranes than in human and guinea-pig brain membranes; affinity in rat and mouse brain membranes was similar. While NECA exhibited 9.3 fold higher affinity in rat compared to human cortical membranes, affinity in other species was comparable. The stable GTP analogue, Gpp(NH)p (100 microM) reduced 2-chloro-N6-cyclopentyladenosine (CCPA) affinity 7-13.9 fold, whereas the affinity of DPCPX was unaffected. 4. The affinity of six xanthine-based adenosine receptor antagonists was 2.2-15.9 fold higher in rat cortical membranes compared with human or guinea-pig membranes. The rank order of potency was species-independent. In contrast, three pyrazolopyridine derivatives, (R)-1-[(E)-3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl) acryloyl]-2-piperidine ethanol (FK453), (R)-1-[(E)-3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl) acryloyl]-piperidin-2-yl acetic acid (FK352) and 6-oxo-3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)-1(6H)-pyridazinebutyric acid (FK838) exhibited similar affinity in human, guinea-pig, rat and mouse brain membranes. pKi values (M) for [3H]-DPCPX binding sites in human cortical membranes were 9.31, 7.52 and 7.92, respectively. 5. Drug affinity for adenosine A2A receptors was determined in a [3H]-2-[4-(2-carboxyethyl)phenethylamino]-5'-N-ethylcarboxamido ade nosine ([3H]-CGS 21680) binding assay in rat striatal membranes. The pyrazolopyridine derivatives, FK453, FK838 and FK352 exhibited pKi values (M) of 5.90, 5.92 and 4.31, respectively, compared with pKi values of 9.31, 8.18 and 7.57 determined in the [3H]-DPCPX binding assay in rat cortical membranes. These novel pyrazolopyridine derivatives therefore represent high affinity, adenosine A1 receptor selective drugs that, in contrast to xanthine based antagonists, exhibit similar affinity for [3H]-DPCPX binding sites in human, rat, mouse and guinea-pig brain membranes.  相似文献   
19.
20.
The authors of “Performance evaluation of steel-conduit-enclosed power systems” (see ibid., vol. 35, no. 3, p. 515-23, 1999) respond to the comments on the original paper. They argue that the intention of their paper is that the users should use the proper value of overcurrent device rating as it will be dictated by the application  相似文献   
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