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31.
In groupware tools, the activation of a function may affect other users who might have conflicting interests. We developed technical mechanisms to support users in resolving them. Contrary to current implementations of groupware tools, these mechanisms strengthen the position of the users who are affected by the activation of said functions. Supporting the visibility of a function's activation, and providing a channel for communication or means to intervene against the function's activation are approaches which constitute a framework to implement these mechanisms. We conclude with showing implementation examples of the framework and their evaluation in the POLITeam project.  相似文献   
32.
4-Nonylphenols (NPs) are common products of biodegradation of a widely used group of nonionic surfactants, the nonylphenol ethoxylates (NPEs). These compounds are known to be persistent, toxic, and estrogen active. There is a worldwide scientific and public discussion on the potential consequences of human long term dietary exposure to such endocrine disrupters. Despite numerous determinations of NPs in environmental samples no systematical reports exist relating to concentrations of NPs in food. We analyzed NPs in 60 different foodstuff commercially available in Germany. The results indicate that NPs are ubiquitous in food. The concentrations of NPs on a fresh weight basis varied between 0.1 and 19.4 microg/kg regardless of the fat content of the foodstuff. Based on data on German food consumption rates and these first analyses of NPs in food, the daily intake for an adult was calculated to be 7.5 microg/day NPs. For infants exclusively fed with breast milk or infant formulas daily intakes of 0.2 microg/day and 1.4 microg/day NPs, respectively, can be estimated.  相似文献   
33.
Given a set $\T$ of rooted, unordered trees, where each $T_i \in \T$ is distinctly leaf-labeled by a set $\Lambda(T_i)$ and where the sets $\Lambda(T_i)$ may overlap, the maximum agreement supertree problem~(MASP) is to construct a distinctly leaf-labeled tree $Q$ with leaf set $\Lambda(Q) \subseteq $\cup$_{T_i \in \T} \Lambda(T_i)$ such that $|\Lambda(Q)|$ is maximized and for each $T_i \in \T$, the topological restriction of $T_i$ to $\Lambda(Q)$ is isomorphic to the topological restriction of $Q$ to $\Lambda(T_i)$. Let $n = \left| $\cup$_{T_i \in \T} \Lambda(T_i)\right|$, $k = |\T|$, and $D = \max_{T_i \in \T}\{\deg(T_i)\}$. We first show that MASP with $k = 2$ can be solved in $O(\sqrt{D} n \log (2n/D))$ time, which is $O(n \log n)$ when $D = O(1)$ and $O(n^{1.5})$ when $D$ is unrestricted. We then present an algorithm for MASP with $D = 2$ whose running time is polynomial if $k = O(1)$. On the other hand, we prove that MASP is NP-hard for any fixed $k \geq 3$ when $D$ is unrestricted, and also NP-hard for any fixed $D \geq 2$ when $k$ is unrestricted even if each input tree is required to contain at most three leaves. Finally, we describe a polynomial-time $(n/\!\log n)$-approximation algorithm for MASP.  相似文献   
34.
We describe an approach for the combination of biomolecular interaction analysis (BIA) and electrospray tandem mass spectrometry (ESI/MS/MS) to obtain sequence information on the affinity-bound proteins on the sensor chip of BIA. The procedure is illustrated with stable and unstable interactions of recombinant proteins, i.e., histidine-tagged protein-Ni2+/NTA and 1,4,5-inositol trisphosphate receptor-ligand interactions. The E. coli lysates expressing the recombinant proteins were passed through the sensor chips, and biomolecular interactions were monitored in real time. The molecules detected on the sensor chip were digested by delivering proteolytic enzyme to the sensing flow cells. The resulting on-chip digested peptide mixture at the mid- to low-femtomole level was recovered on a microcapillary reversed-phase precolumn by an on-line system and analyzed using HPLC-MS/MS. In both cases, unambiguous sequence information on the recombinant proteins isolated on the sensor chip was obtained from only a single run of analysis. The combined BIA-MS/MS may prove to be a general and versatile system to discover novel biomolecular interactions and to analyze protein complexes.  相似文献   
35.
In an earlier paper, a “new” viscoelastic function, log J2 = g{log J1}, was defined. For polymers, the linear viscoelastic behavior of which is characterized by “simple segment movements” in their main transition regions, the following general properties are found: (1) The local maxima of the function for different polymers fall along a straight line width the slope approximately equal to 1.1. (2) A characteristical general shape is noticed for the function after shifting along the straight line and reducing the J1 compliance as regards the “frozen in” compliance J10. (3) J1 reflects the storage and J2, the loss mechanisms of the system. The relation J2/J1 is an expression for the average retardation time.  相似文献   
36.
Environmental engineering education at universities is a rapidly changing field globally. Traditionally it has resided in the civil engineering program addressing water and wastewater quality, treatment, design and regulatory issues. In recent years environmental engineering has become a much broader field encompassing water, wastewater, soil pollution, air pollution, risk assessment, ecosystems, human health, toxicology, sustainable development, regulatory aspects and much more. The need to introduce environmental engineering/green engineering/pollution prevention/design for the environment concepts to undergraduate engineering students has become recognized to be increasingly important. This need is being driven in part through the US Engineering Accreditation Commission Accreditation Board for Engineering and Technology criteria 2000. Thus there has been a major shift in environmental engineering education and it no longer resides only within the civil engineering discipline. This paper focuses on the development of innovative curricula for a brand new engineering program at Rowan University that integrates environmental education for all engineers. A common course known as "engineering clinic" was developed for all engineering students throughout their eight semesters of engineering education. One of the clinic goals is to integrate engineering design and the environment. The program, in its seventh year, indicates successful implementation of environmental education in all four engineering disciplines in their course work and clinics.  相似文献   
37.
A fast and convenient method for on-line monitoring of the extraction of heavy metals from solid (environmental) matrixes was developed. By the incorporation of microcartridges filled with dried and pulverized solid samples into the conduits of a flow system and appropriate selection of the liquid flowing through the cartridge, information about the degree of leaching and in particular of the kinetics of the leaching process are obtained. The method was optimized for determination of different metals of environmental concern using in-line detection by FAAS and ICPMS.  相似文献   
38.
39.
The purpose of this paper is to propose and discuss a new method for information acquisition called collegial verbalisation. The method is explored in an empirical case study, and it consists of vehicle operators being videotaped while driving, followed by some of their colleagues making verbal reports while watching the video data. These colleagues have previously experienced exactly the same driving task as the operators, that is, they have travelled the same route, with the same craft, and used the same instrumentation. Thus, they are very familiar with the driving task and the driver environment. The empirical study is carried out on a high-speed ferry. The method is explored in relation to three rather open hypotheses: the amount of information provided in general; the reliability of the data; and how it contributes to the detection of 'buggy mental models' within the operators. The method is discussed in relation to the more traditional forms of verbal reports: concurrent and retrospective verbalisations, respectively. From the results of the empirical exploration, it is suggested that the method of collegial verbalisation may have combinatorial advantages that makes it more powerful as an analytical tool than the traditional forms of verbalisation, specifically if one wants to analyse work tasks that are dynamic and where the operators' behaviours are highly automated. However, more elaborate and systematic investigations must be conducted on the topic, and the paper therefore ends with a suggestion on an experimental design for this purpose.  相似文献   
40.
The aim of this study was to assess the potential impacts of future climate change on the hydrological response in the upper reach of the Spree River catchment using the Soil and Water Assessment Tool (SWAT). The model was calibrated for ten years (1997–2006) and validated with the data from four years (2007–2010) using average monthly stream flow. The impact of future climate change on precipitation, temperature, evapotranspiration and stream flow was then investigated from two different downscaled climate models (CLM and WETTREG2010) under SRES A1B scenarios for two future periods (2021–2030 and 2041–2050). Besides that, sensitivity analysis was carried out with and without observations, to test robustness of the sensitivity algorithm used in the model. Results of the determination coefficient R2 and Nasch-Sutcliff efficiency ENC were 0.81 and 0.80, respectively, during the calibration; 0.71 and 0.70, respectively, during the validation. Although some parameters were changed their sensitiveness ranking when the model run with observations, the SWAT model was, however, able to predict the top influential parameters without observations. According to 12 realizations from the two downscaled climate models, annual stream flow from 2021–2030 (2041–2050) is predicted to decrease by 39 % (43 %). This corresponds to an increase in annual evapotranspiration from 2021–2030 (2041–2050) of 36 % (38 %). The upper reach of the Spree River catchment will likely experience a significant decrease in stream flow due to the increasing in the evapotranspiration rates. This study could be of use for providing insight into the availability of future stream flow, and to provide a planning tool for this area.  相似文献   
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