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Mahmood Q Siddiqi MR Islam Eu Azim MR Zheng P Hayat Y 《Journal of Zhejiang University. Science. B》2005,6(10):991-998
Water hyacinth (Eichhornia crassipes (Mart.) Solms) is a prolific free floating aquatic macrohpyte found in tropical and subtropical parts of the earth. The effects
of pollutants from textile wastewater on the anatomy of the plant were studied. Water hyacinth exhibits hydrophytic adaptations
which include reduced epidermis cells lacking cuticle in most cases, presence of large air spaces (7∼50 μm), reduced vascular
tissue and absorbing structures. Textile waste significantly affected the size of root cells. The presence of raphide crystals
was noted in parenchyma cells of various organs in treated plants.
Project (No. 30070017) supported by the National Natural Science Foundation of China 相似文献
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Al-Abood SA Bennett SJ Hernandez FM Ashford D Davids K 《Journal of sports sciences》2002,20(3):271-278
We assessed the effects on basketball free throw performance of two types of verbal directions with an external attentional focus. Novices (n = 16) were pre-tested on free throw performance and assigned to two groups of similar ability (n = 8 in each). Both groups received verbal instructions with an external focus on either movement dynamics (movement form) or movement effects (e.g. ball trajectory relative to basket). The participants also observed a skilled model performing the task on either a small or large screen monitor, to ascertain the effects of visual presentation mode on task performance. After observation of six videotaped trials, all participants were given a post-test. Visual search patterns were monitored during observation and cross-referenced with performance on the pre- and post-test. Group effects were noted for verbal instructions and image size on visual search strategies and free throw performance. The 'movement effects' group saw a significant improvement in outcome scores between the pre-test and post-test. These results supported evidence that this group spent more viewing time on information outside the body than the 'movement dynamics' group. Image size affected both groups equally with more fixations of shorter duration when viewing the small screen. The results support the benefits of instructions when observing a model with an external focus on movement effects, not dynamics. 相似文献
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In this paper, we propose an optimization framework to retrieve an optimal group of experts to perform a multi-aspect task. While a diverse set of skills are needed to perform a multi-aspect task, the group of assigned experts should be able to collectively cover all these required skills. We consider three types of multi-aspect expert group formation problems and propose a unified framework to solve these problems accurately and efficiently. The first problem is concerned with finding the top k experts for a given task, while the required skills of the task are implicitly described. In the second problem, the required skills of the tasks are explicitly described using some keywords but each expert has a limited capacity to perform these tasks and therefore should be assigned to a limited number of them. Finally, the third problem is the combination of the first and the second problems. Our proposed optimization framework is based on the Facility Location Analysis which is a well known branch of the Operation Research. In our experiments, we compare the accuracy and efficiency of the proposed framework with the state-of-the-art approaches for the group formation problems. The experiment results show the effectiveness of our proposed methods in comparison with state-of-the-art approaches. 相似文献
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Khalid M Yang WJ Kishwar N Rajput ZI Arijo AG 《Journal of Zhejiang University. Science. B》2006,7(6):459-466
This study is aimed at identifying and determining the percentage of occurrence frequency of cellulose decomposing soil fungi. The soil samples were inoculated into culture plates prepared in Sabouraud medium under sterilized conditions and incubated at 30 ℃ for 4 to 7 d. The identified fungal species were incubated in self-designed cellulose medium for testing their cellulolytic ability. Forty-two species, including2 nova species, representing sixteen genera showed growth and sporulation in the cellulose medium. Most of the isolated species were from genus Aspergillus and Penicillium. Aspergillus niger and Mucor hiemalis showed highest occurrence frequency (45% and 36% respectively), as these species were collected from about 80% of soil samples. Being agar free and cheaper, the new fungal medium designed showed results equivalent to Sabouraud medium. 相似文献
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Nisreen Ameen Robert Willis Media Noori Abdullah Mahmood Shah 《British journal of educational technology : journal of the Council for Educational Technology》2019,50(3):1434-1446
This study aims to analyse the factors that can explain the adoption and effective use of a new e-learning system in Iraq. To achieve this, it uses a selection of factors that are present in the technology acceptance model (TAM) and the unified theory of acceptance and use of technology (UTAUT) model, and it includes three additional factors. The study hypothesises new relationships between the selected factors. Questionnaires were distributed to 300 university students in Iraq. Partial least squares-structural equation modelling (PLS-SEM) was used to analyse the data received. The findings suggest that perceived usefulness (PU), perceived ease of use (PEOU), subjective norms (SNs), information quality (IQ), system quality (SQ), technical support (TS) and self-efficacy (SE) have significant effects on behavioural intention (BI). In turn, BI and TS have significant direct effects on the actual use (AU) of e-learning systems. The factors age, gender and experience significantly moderated some of the relationships in the model. The research has several implications for policy makers, universities and the management of e-learning systems. 相似文献
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Faculty use of technology is a critical issue in higher education; administrators and students are expecting faculty instruction
to incorporate technology in classroom and distance education. Competition is demanding technologically proficient graduates
for schools and colleges. Research indicates that computer self-efficacy (CSE) may be one determinant of who uses technology
and who does not. A survey of education faculty at the Lebanese University in Beirut, Lebanon, conducted in 2006, revealed
varying degrees of CSE; of 127 respondents, 14 had low levels of CSE; 68 were at a moderate level, and 45 self-evaluated themselves
to have high CSE. Although other barriers may deter the implementation of technology in teaching, strategies and techniques
for increasing CSE should be developed. For those with low CSE, special attention must be given to enhancing their levels
of CSE.
相似文献
Hanadi Kassem SalehEmail: |