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101.
Scientifically liberated and developed countries produce huge amounts of cutting-edge publications in peer-reviewed impact-creating journals. These publications may become basis for various policies/other blueprints. There is no reported study regarding the publication trends of Periodontists from India. The aim of this study was to assess the trends of Indian Periodontist’s publications in Pubmed database till 1st March, 2012 by taking quantitative bibliometric approach. Studies were identified by running select search phrases on Pubmed search engine. Search inputs included, ‘dental’, ‘oral’, ‘periodontal’, ‘gingiva’, ‘gingival’, ‘periodontology’, ‘periodontics’, ‘periodontia’, ‘periodontitis’, ‘gingivitis’, and ‘dental implant’. A parallel search with above phrases along with ‘India’ also done to assess India-specific publications. All publications with or without available abstracts were analyzed for selected parameters. Analysis was performed to determine name of the journal, number of authors, year of publication, type of institute, statewide distribution, type of study etc. The approximate contribution of Indian Dental/Periodontal literature to Pubmed database is 1.45 % till 1st March 2012. The number of articles published by Indian Periodontists is 764 across 107 journals and starting from 1960. The number of original articles published were 510 (66.75 %) as opposed to 127 (16.62 %) each for review articles and case reports/case series. The average contribution of an Indian Periodontist to Pubmed database is 0.53 articles. The contribution of Indian Periodontists to world literature through Pubmed database is not voluminous but, the publications are multiplying every passing year almost in an exponential way. There is also an increasing trend towards original articles to be published. 相似文献
102.
Xu A. Zhang Abhijeet Bagal Erinn C. Dandley Junjie Zhao Christopher J. Oldham Bae‐Ian Wu Gregory N. Parsons Chih‐Hao Chang 《Advanced functional materials》2015,25(42):6644-6649
The refractive indices of naturally occurring materials are limited, and there exists an index gap between indices of air and available solid materials. With many photonics and electronics applications, there has been considerable effort in creating artificial materials with optical and dielectric properties similar to air while simultaneously being mechanically stable to bear load. Here, a class of ordered nanolattice materials consisting of periodic thin‐shell structures with near‐unity refractive index and high stiffness is demonstrated. Using a combination of 3D nanolithography and atomic layer deposition, these ordered nanostructured materials have reduced optical scattering and improved mechanical stability compared to existing randomly porous materials. Using ZnO and Al2O3 as the building materials, refractive indices from 1.3 down to 1.025 are achieved. The experimental data can be accurately described by Maxwell Garnett effective media theory, which can provide a guide for index design. The demonstrated low‐index, low‐scattering, and high‐stiffness materials can serve as high‐quality optical films in multilayer photonic structures, waveguides, resonators, and ultra‐low‐k dielectrics. 相似文献
103.
With rapid increase in new applications and services, there is huge demand for internet bandwidth. Several researchers around the world have found that, majority of licensed bands (mostly terrestrial TV band) are either unused or underused. These underutilized bands allocated for TV transmission are known as TV white space (TVWS). For effective utilization of TVWS, the IEEE 802.22 is proposed. The IEEE 802.22 wireless regional area network (WRAN) is the latest standard for effective utilization of TV bands. This standard is based on orthogonal frequency division multiplexing with various modulation techniques to provide different data rates. In this paper, an implementation framework for physical layer of IEEE 802.22 WRAN standard for normal mode is demonstrated and analyzed. This transceiver is implemented using the National Instruments Laboratory Virtual Instrument Engineering Workbench programming software on the National Instruments universal software radio peripheral 2952R. We have also analyzed different blocks of IEEE 802.22 based on their execution time, and identify the critical blocks of IEEE 802.22 that should be optimized for real-time applications for commercial product development and field deployments. We have also highlighted the difference between theoretical and practical performance of the considered error control codes for IEEE 802.22 specified block size. Additionally, various covariance based spectrum sensing methods are also analyzed for real-world environment. 相似文献
104.
H.H. Le S. Abhijeet S. Ilisch J. Klehm S. Henning M. Beiner S.S. Sarkawi W. Dierkes A. Das D. Fischer K.-W. Stöckelhuber S. Wiessner S.P. Khatiwada R. Adhikari T. Pham G. Heinrich H.-J. Radusch 《Polymer》2014
The aim of the present work is to evidence the role of the linked phospholipids of natural rubber (NR) in the rubber-carbon nanotube (CNT) interactions in rubber composites. Three rubbers namely NR, deproteinized NR (DPNR) and a synthetic rubber isoprene (IR) were used as matrix for CNTs. The selective wetting of CNTs in miscible NR/IR and DPNR/IR blends was investigated by means of the modified wetting concept based on Fourier transformed infrared (FTIR) analysis of the rubber-filler gel of blends. It revealed that the surface of CNTs is entirely wetted by NR or DPNR molecules, respectively, but not by IR. This result emphasizes that proteins do not influence the affinity between NR and CNTs, while the linked phospholipids interact with CNT surface through cation-π linkage. This linkage acts as anchor point supporting NR molecules to wet CNT surface effectively. The modified wetting concept can be used for characterization of selective wetting of different fillers in blends consisting of miscible rubber components. 相似文献