排序方式： 共有87条查询结果，搜索用时 46 毫秒
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Nadeem Akhtar Abbasi Tariq Pervaiz Ishfaq Ahmed Hafiz Mehwish Yaseen Azhar Hussain 《Journal of Zhejiang University. Science. B》2013,14(9):774-784
In vitro cultures of loquat cultivar Mardan were established using shoot apices after treating with NaOCl (5%, 7%, 10%, 12%, 14% (v/v)) for 12 min and HgCl2 (0.01%, 0.05%, 0.10%, 0.20%, 0.25% (w/v)) for 2 min. A maximum survival rate of 70% was recorded after surface sterilization with 10% NaOCl. Caulogenic response was assessed on Murashige and Skoog (MS) medium fortified with assorted combinations of the cytokinins, benzylaminopurine (BAP), kinetin, and N6-(2-isopentyl)adenine (2iP). Treatment of BAP 1.5 mg/L combined with 2iP 9.0 mg/L and kinetin 1.5 mg/L was found to be optimum for shoot morphogenesis in terms of the number and subsequent growth of shoots, while the highest shoot length was yielded by the combination of BAP 0.5 mg/L, kinetin 0.5 mg/L, and 2iP 3 mg/L. Higher levels of cytokinins induced callogenesis, vitrification and stunted growth to some extent. For rhizogenesis, uniform sized micro-shoots were excised and transferred to half-strength MS medium containing auxins. The best rooting expression was observed with naphthaleneacetic acid (NAA) 1 mg/L combined with indole-3-butyric acid (IBA) 2 mg/L and paclobutrazol (PBZ) 1 mg/L. 相似文献
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Edgar Scavino Dzuraidah Abdul Wahab Aini Hussain Hassan Basri Mohd Marzuki Mustafa 《浙江大学学报(A卷英文版)》2009,10(6):794-799
An experimental machine vision apparatus was used to identify and extract recyclable plastic bottles out of a conveyor belt. Color images were taken with a commercially available Webcam, and the recognition was performed by our homemade software, based on the shape and dimensions of object images. The software was able to manage multiple bottles in a single image and was additionally extended to cases involving touching bottles. The identification was fulfilled by comparing the set of measured features with an existing database and meanwhile integrating various recognition techniques such as minimum distance in the feature space, self-organized maps, and neural networks. The recognition system was tested on a set of 50 different bottles and provided so far an accuracy of about 97% on bottle identification. The extraction of the bottles was performed by means of a pneumatic arm, which was activated according to the plastic type; polyethylene-terephthalate （PET） bottles were left on the conveyor belt, while non-PET bottles were extracted. The software was designed to provide the best compromise between reliability and speed for real-time applications in view of the commercialization of the system at existing recycling plants. 相似文献
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1 Ｉｎｔｒｏｄｕｃｔｉｏｎ Ｉｎｒｅｃｅｎｔｙｅａｒｓ ,ｈｉｇｈ ｐｏｗｅｒｌａｓｅｒｄｉｏｄｅｓｈａｖｅｂｅｅｎｅｍｐｌｏｙｅｄａｓｐｕｍｐｉｎｇｓｏｕｒｃｅｓｗｉｔｈａｖｉｅｗｔｏｄｅｖｅｌｏｐｃｏｍｐａｃｔｕｐ ｃｏｎｖｅｒｓｉｏｎｖｉｓｉｂｌｅ ｌａｓｅｒｓｙｓｔｅｍｓ .Ｔｈｅｆｒｅ ｑｕｅｎｃｙｃｏｎｖｅｒｓｉｏｎｏｆｉｎｆｒａｒｅｄｌｉｇｈｔｔｏｖｉｓｉｂｌｅｌｉｇｈｔｈａｓｂｅｅｎｅｘｔｅｎｓｉｖｅｌｙｉｎｖｅｓｔｉｇａｔｅｄｆｏｒｒａｒｅ ｅａｒｔｈｄｏｐｅｄｃｒｙｓｔａｌｓａｎｄｇ… 相似文献
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This introduction offers an overview of the concept of populism, the debates around its definitions and its relationship with democracy and the significance of attending to populist politics in the context of education. It also lays out the political contexts in which authors have engaged with education and populist politics in the UK, Brazil and Israel, and the ways in which they understand populist shifts in education. Detailing the two main conceptions of populism used by authors in the special section, namely, populism as ideology and populism as political logic, we discuss how authors understand the construction of ‘the people’ and ‘the elite’, and the implications of the ‘antagonism’ between them in each case. Dividing the nine articles in the special section into three groups, we look at the ways in which right-wing populism has sought to (re)shape divisions based on race, religion and nationalities, among other things; how political and pedagogic practices are being (re)imagined to counter these divisions and populist moves; and the stakes of bringing the question of populism into education. We show how this special section has brought together different conversations and disciplinary perspectives on right-wing shifts in education, challenges to these and a potential way forward. Most importantly, we invite readers to think through the shifting role of education in democracy, as well as the divisions and hierarchies that are entailed in institutionalised education. 相似文献
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Ali Saif Al-Aufi Hamed Mohamed Al-Azri Nihad Ali Al-Hadi 《International Information and Library Review》2017,49(3):163-175
This study assessed information literacy perceptions of undergraduate students at Sultan Qaboos University in their use of social media. A quantitative approach was used to collect data from undergraduate students. The study consisted of 1,142 completed questionnaires by randomly selected participants. The results demonstrated overall moderate levels of perceptions toward the evaluation of information, information ethics, legal issues, and privacy issues. In evaluation of information, credibility of information was considered as an important factor to decide whether to use information for academic purposes. This study signifies the importance of understanding perceptions of information literacy among undergraduate students in a specific socio-cultural context. The results can also be generalized to similar academic institutions worldwide. It is also hoped that the study's findings will assist in developing contextual training programs or information literacy quizzes to promote information literacy in the social media environment. 相似文献
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Saif Shahin 《Communication methods and measures》2016,10(1):28-50
As computer-assisted research of voluminous datasets becomes more pervasive, so does the criticism of its epistemological, methodological, and ethical/normative inadequacies. This article proposes a hybrid approach that combines the scale of computational methods with the depth of qualitative analysis. It uses simple natural language processing algorithms to extract purposive samples from large textual corpora, which can then be analyzed using interpretive techniques. This approach helps research become more theoretically grounded and contextually sensitive—two major failings of typical “Big Data” studies. Simultaneously, it allows qualitative scholars to examine datasets that are otherwise too large to study manually and also bring more rigor to the process of sampling. The method is illustrated with two case studies, one looking at the inaugural addresses of U.S. presidents and the other investigating the news coverage of two shootings at an army camp in Texas. 相似文献
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Abdul Latif Khan Syed Abdullah Gilani Muhammad Waqas Khadija Al-Hosni Salima Al-Khiziri Yoon-Ha Kim Liaqat Ali Sang-Mo Kang Sajjad Asaf Raheem Shahzad Javid Hussain In-Jung Lee Ahmed Al-Harrasi 《Journal of Zhejiang University. Science. B》2017,18(2):125-137
Medicinal plants have been used by marginal communities to treat various ailments. However, the potential of endophytes within these bio-prospective medicinal plants remains unknown. The present study elucidates the endophytic diversity of medicinal plants (Caralluma acutangula, Rhazya stricta, and Moringa peregrina) and the endophyte role in seed growth and oxidative stress. Various organs of medicinal plants yielded ten endophytes, which were identified as Phoma sp. (6 isolates), Alternaria sp. (2), Bipolaris sp. (1), and Cladosporium sp. (1) based on 18S rDNA sequencing and phylogenetic analysis. The culture filtrates (CFs; 25%, 50%, and 100% concentrations) from these endophytes were tested against the growth of normal and dwarf mutant rice lines. Endophytic CF exhibited dose-dependent growth stimulation and suppression effects. CF (100%) of Phoma sp. significantly increased rice seed germination and growth compared to controls and other endophytes. This growth-promoting effect was due to the presence of indole acetic acid in endophytic CF. The gas chromatography/mass spectrometry (GC/MS) analysis showed the highest indole acetic acid content ((54.31±0.21) μmol/L) in Bipolaris sp. In addition, the isolate of Bipolaris sp. exhibited significantly higher radical scavenging and anti-lipid peroxidation activity than the other isolates. Bipolaris sp. and Phoma sp. also exhibited significantly higher flavonoid and phenolic contents. The medicinal plants exhibited the presence of bio-prospective endophytic strains, which could be used for the improvement of crop growth and the mitigation of oxidative stresses. 相似文献
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Essa ALI Nazim HUSSAIN Imran Haider SHAMSI Zahra JABEEN Muzammil Hussain SIDDIQUI Li-xi JIANG 《Journal of Zhejiang University. Science. B》2018,(2)
目的:本研究目的在于了解:(1)喷施外源茉莉酸对受到镉胁迫油菜的作用;(2)是否茉莉酸能够通过增强气体交换,从而保护受到氧化胁迫的地上部分组织的叶绿体,进而通过减少镉的吸收来维持离子平衡;(3)是否通过喷施茉莉酸来对具有减缓镉毒害效应的抗氧化酶的活性进行调节。创新点:茉莉酸能够调节响应胁迫的抗氧化酶的活性,从而通过保护叶绿体免受活性氧(ROS)伤害而提高光合产物的能力,最大限度地缓解油菜植株受到的镉毒害。方法:(1)叶片气体交换;(2)叶片光合色素分析;(3)丙二醛与抗氧化酶活性分析;(4)营养成分分析;(5)透射电镜亚细胞水平观察。结论:茉莉酸对于植物受镉毒害的缓解作用的机理在于减少叶片中镉的积累,从而减轻氧化胁迫过程中产生的ROS对于膜系统的损害程度。 相似文献
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Kamal Ahmed Soomro Sajid Yousuf Zai Iftikhar Hussain Jafri 《Educational Media International》2013,50(4):284-295
Literature on Web 2.0 experiences of higher education faculty in developing countries such as Pakistan is very limited. An insight on awareness and practices of higher education faculty with these tools can be helpful to map strategies and plan of action for adopting latest technologies to support teaching–learning processes in higher education of such countries. This survey study was aimed to examine the competence and practices of higher education faculty in Pakistan with Web 2.0 technologies such as blogs, Wikis, Google Docs, Skype, Flickr, YouTube, and social networks. The study was also focused to look for what type of role faculty play while using these tools; and to find whether any significant differences in terms of age, gender, or academic discipline exist in competence and usage of these tools by the faculty. The data were collected from a sample of 246 university teachers in the spring 2014 semester. The findings of the study indicated that faculty participants reported to use Web 2.0 social tools more frequently than instrumental tools. Similarly, their competence with social tools was higher than their competence with instrumental tools. Additional results indicated that their competence with Web2.0 tools significantly differed with respect to their age, gender, and academic disciplines. 相似文献