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51.
Sohaib Ahmed Sameena Javaid Moazzam Fareed Niazi Anzar Alam Adnan Ahmad Murad Ali Baig 《Technology, Pedagogy and Education》2019,28(1):53-71
The use of Bluetooth Low Energy (BLE) beacons is becoming widespread for context-aware learning environments. This technology can be used in indoor and outdoor settings such as museums, shops, home and schools in order to identify the location of learners and their contexts. Specifically, in the constructivist view of learning, learners can use such sensing technology for constructing knowledge and experiencing learning at any time, anywhere. However, exploration of such technology has been limited in the constructivist context-aware ubiquitous learning (U-learning) literature. For this purpose, the authors evaluated two android-based U-learning applications: one was an outdoor learning environment in a garden, the other was about locating books in a library. The applications were implemented and tested with school and university students. The qualitative results are presented in this article, and show how such sensing technology is promising for both pedagogical environments. 相似文献
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Ines Ben Chobba Amine Elleuch Imen Ayadi Lamia Khannous Ahmed Namsi Frederique Cerqueira Noureddine Drira Néji Gharsallah Tatiana Vallaeys 《Journal of Zhejiang University. Science. B》2013,14(12):1084-1099
Endophytic flora plays a vital role in the colonization and survival of host plants, especially in harsh environments, such as arid regions. This flora may, however, contain pathogenic species responsible for various troublesome host diseases. The present study is aimed at investigating the diversity of both cultivable and non-cultivable endophytic fungal floras in the internal tissues (roots and leaves) of Tunisian date palm trees (Phoenix dactylifera). Accordingly, 13 isolates from both root and leaf samples, exhibiting distinct colony morphology, were selected from potato dextrose agar (PDA) medium and identified by a sequence match search wherein their 18S–28S internal transcribed spacer (ITS) sequences were compared to those available in public databases. These findings revealed that the cultivable root and leaf isolates fell into two groups, namely Nectriaceae and Pleosporaceae. Additionally, total DNA from palm roots and leaves was further extracted and ITS fragments were amplified. Restriction fragment length polymorphism (RFLP) analysis of the ITS from 200 fungal clones (leaves: 100; roots: 100) using HaeIII restriction enzyme revealed 13 distinct patterns that were further sequenced and led to the identification of Alternaria, Cladosporium, Davidiella (Cladosporium teleomorph), Pythium, Curvularia, and uncharacterized fungal endophytes. Both approaches confirmed that while the roots were predominantly colonized by Fusaria (members of the Nectriaceae family), the leaves were essentially colonized by Alternaria (members of the Pleosporaceae family). Overall, the findings of the present study constitute, to the authors’ knowledge, the first extensive report on the diversity of endophytic fungal flora associated with date palm trees (P. dactylifera). 相似文献
55.
Mohamed Taher Amin Ahmed Khan Muhammed Burhanuddin 《International Information and Library Review》2013,45(4):337-345
This paper relates to the difficulty in retrieving precise information from big repositories of magazine articles in full text, and proposes an Extended Markup Language (XML) vocabulary for improving retrieval rates. The hypothesis tested was as follows: Magazine articles marked up with an XML vocabulary, indexed only by selected parts, give more precise search results than the same search using full text index.The study was exploratory with the following characteristics: 29 magazine articles were tested for results, 8 scholars were interviewed for defining 23 search strategies and evaluating results. The data showed that precision improved from 40.72% with full text search to 62.84% using XML markup and searching only in specific labels.Revision of the vocabulary and more testing has to be done by the library and information science community in order to obtain a valid vocabulary and provide more research results. Cultural characteristics and politics of librarians and information managers’ community are as important as technical issues in order to consider any technical proposal to be implemented successfully to achieve interoperability. 相似文献
56.
Tariq Ashraf 《International Information and Library Review》2013,45(3):148-152
The beginning of the 21st century is marked with the developments made in the field of information and technology. The primary role of the information is to equip the citizens to make informed choices. Information is life blood that sustains political, social and business decisions. It may pertain to quality, quantity, standard, and prices of products or services that are needed to make an informed decision. This is particularly true in a country where government and its numerous administrative agencies have expanded in a bewildering manner.The Right to Information Act, passed by the Indian Parliament in the year 2005 has proved to be a landmark for good governance and in helping common people, especially the poor and underprivileged, get their dues from the government. The act has emerged as the most potent tool to empower ordinary citizens to combat state corruption and to play an important and active role in participatory democracy. Drafted by civil society itself, the law is unique in the sense that it has been the result of years of struggle by civil society, NGOs and media. 相似文献
57.
Extensive use of social networking sites by students and teachers makes educators and researchers to think whether they can be incorporated in instructional process to facilitate students’ learning. This survey-based study records and examines Pakistani pre-service teachers’ and teacher-educators’ current uses of Facebook, and their attitudes toward using Facebook for collaborative learning, and to see if there is a significant relationship between participants’ intensity of Facebook use and their attitude toward instructional use of Facebook. Results of the study indicated that pre-service teachers’ and teacher-educators’ motives for their current Facebook use are mainly limited for social purposes. Pre-service teachers’ use of Facebook is more intensified than the use of Facebook by teacher-educators. Further, pre-service teachers showed more positive attitudes toward using Facebook for collaborative learning than the attitudes of their faculty. Findings also indicated a positive relationship between participants’ Facebook intensity and their attitudes toward its use for collaborative learning. 相似文献
58.
Suvidya H. Ranade Ashraf Hossani D. N. Deobagkar D. D. Deobagkar B. A. Chopade Pramod S. Khandekar 《Indian journal of clinical biochemistry : IJCB》2009,24(2):142-149
We report complete sequences of 2 genes of S.flexneri 1a an Indian isolate for the first time. Shigella is causative agent
of shigellosis or bacillary dysentery. Genomic library was constructed by shotgun approach. Sequencing was carried out using
Big Dye terminator chemistry using ABI 3730 48 capillary DNA analyzer. 170 recombinants were subjected to nucleotide sequencing.
Sequence data was analyzed, of these 2 clones showed presence of complete genes out of the total clones sequenced. Annotations
were done using various bioinformatics tools. Gene Sfo676 on contig SF21B11, 513 bp long codes for a protein 170 aa long with
molecular weight of 18836.5 daltons. The protein is 99 % identical to S. flexneri 2a 301 and not with any other strain of
Shigella. It has 7 different sites for phosphorylation, myristoylation and glycosylation. Predicted cellular localization
is cytoplasmic membrane. SF0368 is another full-length gene SF0368 on contig SF69C1 is a 312 nucleotide long. It is 103 aa
long with molecular weight 11394.0 daltons. Protein is 100% identical to S. flexneri 2a 301 and 99% with S. sonnei strain
046. The gene shows difference when compared with S.sonnei in mono and dinucleotide frequency as well as amino acid composition. 相似文献
59.
Shrish Bhatnagar Farzana K. Beig Ashraf Malik 《Indian journal of clinical biochemistry : IJCB》2008,23(3):299-301
Adenosine deaminase and C-reactive protein in CSF were assessed in 72 cases of Tubercular meningitis, 24 cases of partially
treated pyogenic meningitis, 20 cases of Aseptic meningitis and 8 cases of febrile seizures. Mean Adenosine deaminase value
was 12.12±3.13 IU/L for Tubercular meningitis group. It was significantly higher (p<0.001) as compared to partially treated
pyogenic meningitis (5.39±2.70 IU/L) and aseptic meningitis (1.92±0.56 IU/L) groups. A combination of clinical criteria along
with biochemical test of Adenosine deaminase and C-reactive protein in CSF increased the sensitivity of diagnosing Tubercular
meningitis and differentiating it from other forms of meningitis at an early stage. 相似文献
60.
A new active R filter which realizes a second order bandpass transfer function is given. The network employs only resistors and two operational amplifiers. Sensitivities to all passive and active circuit components are very low. Design equations are given and experimental results are also included. 相似文献