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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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Andrew P. Davidson Munir Ahmad 《The Journal of Agricultural Education and Extension》2013,19(3):117-126
Worldwide serious reservations are being expressed about the ability and competency of the public sector to deliver agricultural extension services, especially in developing countries such as Pakistan which is faced with serious financial difficulties. Consequently, the government is looking for alternative extension paradigms that are cost-effective and client-oriented. To this end the government of Pakistan is inclined towards privatizing the provision of agricultural extension services as a means to promote a second ‘Green Revolution’. This study was conducted among cotton farmers in the Punjab Province to examine the comparative effectiveness of public and private sector extension as perceived from the stakeholders. Data were collected from 52 contact farmers of both extension systems. A number of biases were identified in both systems; namely, a preference for farmers with better education and larger landholdings than their noncontact farmer counterparts. Overall, neither system appears to be working for the benefit of the wider farming community. 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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Sultana S. Zaman Shirin Z. Munir 《International Journal of Disability, Development & Education》1992,39(1):3-11
SPECIAL EDUCATION in Bangladesh reflects the overall educational problems faced by the nation. While some government programs for children with sensory disabilities are provided, most special education is supported by non‐government organizations. Though planning for improved special education has occurred, implementation has been restricted by economic constraints. 相似文献
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Mahar Ali Nawaz Munir Muhammad Elawad Sami Gowen Simon Richard Hague Nigel Graham Meckenzi 《浙江大学学报(A卷英文版)》2004,5(10):1183-1190
Cells and cell-free solutions of the culture filtrate of the bacterial symbiont, Xenorhabdus nematophila taken from the entomopathogenic nematode Steinernema carpocapsae in aqueous broth suspensions were lethal to larvae of the diamondback moth Plutella xylostella. Their application on leaves of Chinese cabbage indicated that the cells can penetrate into the insects in the absence of
the nematode vector. Cell-free solutions containing metabolites were also proved as effective as bacterial cells suspension.
The application of aqueous suspensions of cells of X. nematophila or solutions containing its toxic metabolites to the leaves represents a possible new strategy for controlling insect pests
on foliage. 相似文献