排序方式： 共有54条查询结果，搜索用时 62 毫秒
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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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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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Helen A. Maniati 《Science & Education》2005,14(7-8):713-720
In the current paper, the reasons why the late 19th century Greek university community of natural scientists used elements
from the History of Natural sciences which refer exclusively to ancient Greek science, and the consequences of such a choice
are evaluated. Emphasis will be given to the speech delivered by the Dean, Professor of Chemistry, A. K. Hristomanos, entitled
“Natural Sciences and Progress”, at the National University on 17th of December 1896, where, without nullifying the Scientific
Revolution of the Modern Period, he attempted the analysis of its cognitive continuity with antiquity and the authority of
the ancestral past. Hristomanos’ name was linked to almost all the attempts at reforming and spreading natural sciences in
the late 19th century, and from this point of view his speech, and the way in which it is structured, become a reliable indicator
in tracing theses and viewpoints within the entirety of the scientific community of natural scientists. 相似文献
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Mahmood Khalil Reuven Lazarowitz Rachel Hertz-Lazarowitz 《Journal of Science Education and Technology》2009,18(1):85-100
In this paper a conceptual model of instruction “the six mirrors of the classroom” used as a frame for teaching a learning
topic, the microorganisms are depicted. The paper consists of four sections: (a) the six mirrors of the classroom model (SMC);
(b) the SMC as implemented in the expository and cooperative modes of instruction in classrooms and results; (c) a “Journey
of Inquiry into the Wonderful World of Microorganisms” (JIWWM), developed according to the Science–Technology–Environment–Peace–Society
(STEPS) approach; and (d) teaching and learning the JIWWM, in ninth-grade classes, within the SMC model. The results show
that science topic can be taught in the frame of the mirrors of the classroom. When the instructional goals of the teachers
used the mirror “1, classroom organization” and mirror “6, pupils’ social behavior” and the third ring around the all six
mirrors cooperative skills were practiced, academic outcomes were achieved, and attitudes toward environmental preservation
and peace improved. The SMC model can serve as a valuable tool for teachers, since it can design their teaching and learning
settings in a more controlled environment, in terms of objectives, teachers’ and students’ social behaviors, and academic
outcomes. 相似文献
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Antonio Dello Iacono Domenico Martone Alessandro Moura Zagatto Yoav Meckel Mahmood Sindiani Mirjana Milic 《Journal of sports sciences》2018,36(1):14-22
This study aimed to investigate the effect of contact (C-SSG) and no-contact (NC-SSG) handball small-sided games (SSGs) on motion patterns and physiological responses of elite handball players. Twelve male handball players performed 10 C-SSG and 10 NC-SSG while being monitored through the heart rate (HR) and rate of perceived exertion (RPE) as physiological responses and time-motion activities profile using video-match analysis. Both game conditions resulted in similar HR responses (P > 0.05), but the NC-SSG led to a higher RPE scores. The time-motion activity analysis featured NC-SSG with a greater amount of walking (855.6 ± 25.1 vs. 690.6 ± 35.2 m) and backward movements (187.5 ± 12.3 vs. 142.5 ± 8.7 m) combined with fast running (232.3 ± 8.5 vs. 159.7 ± 5.7 m) and sprinting (79.5 ± 4.7 vs. 39.7 ± 3.7 m) activities (P < 0.001). Conversely, C-SSG had a higher percentage of jogging and sideway movements associated with greater frequency of jumping (0.87 ± 0.09 vs. 0.31 ± 0.06 nr) and physical contact (1.82 ± 0.55 vs. 0.25 ± 0.03 nr) events (P < 0.001). No between-regimen differences were found for the number of throws (P = 0.745). In addition, the RPE was significantly correlated with fast running relative distances (r = 0.909, P < 0.001) and sprinting relative distances (r = 0.939, P < 0.001). In conclusion, this investigation showed that both C-SSG and NC-SSG in team handball can effectively represent specifically oriented exercises, according to the sport-task and the performance demands. 相似文献