305,576 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
sj-docx-2-dhj-10.1177_20552076221102768 - Supplemental material for Telemedicine options to address identified health needs in Botswana
No full textSupplemental material, sj-docx-2-dhj-10.1177_20552076221102768 for Telemedicine options to address identified health needs in Botswana by Benson Ncube, Maurice Mars and Richard E Scott in Digital Health</p
sj-docx-1-dhj-10.1177_20552076221102768 - Supplemental material for Telemedicine options to address identified health needs in Botswana
No full textSupplemental material, sj-docx-1-dhj-10.1177_20552076221102768 for Telemedicine options to address identified health needs in Botswana by Benson Ncube, Maurice Mars and Richard E Scott in Digital Health</p
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Development of a fungal cellulolytic enzyme combination for use in bioethanol production using hyparrhenia spp as a source of fermentable sugars
No full textThesis (PhD. (Microbiology)) --University of Limpopo, 2013The current study investigated four fungal species namely Aspergillus niger FGSC A733,
Aspergillus versicolor EF23, Penicillium citrinum AZ01 and Trichoderma harzianum NCGR
0509 for their abilities to produce cellulases and xylanases in submerged and solid state fermentations. Five different substrates (carboxymethyl cellulose, xylan, common thatch grass, wheat bran and Jatropha curcas seed cake) were examined for their potential use as low cost feedstock for fermentation by the fungal species. Aspergillus niger FGSC A733 produced the highest titres of cellulase and xylanase in solid state fermentations using wheat
bran as a substrate. However, because of the need to lower the cost of enzyme production,
Jatropha seed cake a relatively underutilised oilseed cake was used.
Supplementation of the Jatropha seedcake with 10% common thatch grass (Hyperrhenia sp)
resulted in a fivefold increase in the levels of xylanase produced. Cellulase production was not affected by this supplementation. Addition of ammonium chloride increased production
of xylanase while cellulase production was not affected nitrogen supplementation. Maximum xylanase was produced on Jatropha seed cake at 25 °C after 96 hours while cellulase was maximally produced at 40 °C after 96 hours of solid state fermentations. Peak production of xylanase was obtained at an initial pH of 3 whilst cellulase was maximally produced at an
initial pH of 5. The crude xylanase was most active at pH 5 and cellulase at pH 4. The
optimum temperature for cellulase activity was 65 °C and that of xylanase was 50 °C. Under optimized conditions, 6087 U/g and 3974 U/g of xylanase and cellulase per gram of substrate used were obtained respectively.
The diversity of cellulases was investigated so as to determine the most appropriate enzyme mixture for saccharification of the common thatch grass. Proteins from the four species under investigation were partially purified by affinity chromatography on swollen Avicel. The proteins were analysed using sodium dodecyl sulphate-polyacrylamide gel electrophoresis SDS-PAGE and zymography. Potential cellulase bands from SDS-PAGE were sequenced by mass spectrometry. The basic logical alignment tool (BLAST) and Clustal W were used for matching and identifying the sequences with closely related ones in the databases. The identified proteins from Penicillium citrinum AZ01 and Aspergillus versicolor EF23 were found to closely resemble a catalytic domain of cellobiohydrolase from Trichoderma sp. The
three proteins obtained from Aspergillus niger showed resemblance to 1,4-beta glucan
cellobiohydrolase A precursor from Aspergillus niger FGSC A733 was also found to have cellobiase and endoglucanase activity was determined using cellobiase and carboxymethyl cellulose as substrates. Cellulase and xylanase zymograms of proteins from A. niger FGSC A733 demonstrated six active bands ranging from 20 kDa to 43 kDa for cellulase and a 31 kDa active band for xylanase. The cellulase produced by Aspergillus niger FGSC A733 on Jatropha seed cake under
optimised conditions was used for saccharification of 2% (w/v) common thatch grass (CTG) in combination with Celluclast™. Celluclast™ and Aspergillus niger cellulase were mixed at different ratios and the amount of glucose produced over time was monitored using high performance liquid chromatography (HPLC). A ratio of 2 volumes Celluclast™ to one volume Aspergillus niger cellulase was chosen for the saccharification process. The main
enzymes in the mixture were identified using peptide mass fingerprinting as endoglucanases
from the Celluclast™ and cellobiase from the Aspergillus niger cellulase. Concentration of
the Celluclast™ tenfold times (164 FPU) improved the yield of glucose by 42.8 and 37.8% in acid and alkali pre-treated CTG, respectively. Concentrating Aspergillus niger cellulase (13.2 FPU) decreased the production of glucose by 4.8% in acid pre-treated CTG while in alkali pre-treated CTG, a 5% increase in glucose production was observed. Increasing the substrate
loading of acid pre-treated CTG from 2% to 10% (w/v) resulted in a two and a half times
increase in glucose production while an increase of 1.5 g/l glucose was obtained from 7% (w/v) alkali pre-treated CTG. Addition of xylanases from Aspergillus niger to the Celluclast™-Aspergillus niger cellulase mixture decreased glucose production by 16.3% on acid pre-treated CTG while there was an increase of 18.3% glucose in alkali pre-treated CTG. Addition of enzyme preparations from Aspergillus versicolor EF23, Penicillium citrium
AZ01 and Trichoderma harzianum NCGR 0509 to the Celluclast™-Aspergillus niger cellulase mixture resulted in lower glucose production both in acid and alkali pre-treated CTG. Addition of Pentopan™ improved glucose production by 8 and 25% on 10% acid and
7.5% alkali loading of pre-treated CTG respectively. The optimal conditions for the
production of the glucose rich hydrolysate in 10% (w/v) acid and 7% (w/v) alkali pre-treated CTG was found to be the use of Celluclast™-Aspergillus niger cellulase-Pentopan™ mixture (164 FPU Celluclast™ and 13 FPU Aspergillus niger cellulase, 7178 IU) Pentopan™ at 50 °C for 32 hours. The fermentability of the glucose in glucose-rich CTG hydrolysates to ethanol using
Saccharomyces cerevisae WBSA 1386 and Candida shehatae CSIR Y-0492 was investigated. The highest yield of ethanol produced by S. cerevisae WBSA 1386 was 9.8 g/l in the alkali pre-treated CTG hydrolysate and 8.7 g/l in acid pre-treated CTG. C. shehatae CSIR Y-0492 produced 9 g/l of ethanol in alkali pre-treated CTG within 48 hours while acid
pre-treated CTG hydrolysate produced 8.8 g/l of ethanol within 24 hours of the fermentation process. Addition of the nutrient supplement boosted the ethanol yield in the acid pre-treated hydrolysates. The consumption of glucose during fermentation by S. cerevisae WBSA 1386
and C. shehatae CSIR Y-0492 on average was 97%. The C. shehatae CSIR Y-0492 was
expected to produce much higher ethanol yield than the Saccharomyces because of its ability to utilize xylose for ethanol production. This however was not observed in this investigation. The conclusion of this study is that it is possible to produce bioethanol from Hyperrhenia
spp. (CTG) using a combination of fungal enzymes for the production of fermentable sugars
nCube: The First Norwegian Student Satellite
No full textnCube is a picosatellite complying with the CubeSat standard. It is built completely by students in their final year of their Master education in different Norwegian Institutes. The cross institutional project is mainly sponsored by Norwegian space related industry. The satellite is due to launch March 2004 from Dnepr in Ukraine. The concept incorporates use of a miniaturized version of an Automatic Identification System receiver which will be uploaded the coordinates of reindeer herds, making the Agricultural University of Norway able to track them. The satellite will also be able to surveillance regular marine traffic with certain filter options. nCube is equipped with instruments to determine the attitude based both on solar cell lighting conditions and measurements on the earth magnetic field. Two techniques of controlling the attitude are implemented; by the use of magnetic coils, and gravity gradient stabilization. Communication with the satellite is achieved by the use of AMSAT frequencies in the amateur band and the AX.25 protocol. The project has built its own ground station, which is situated in Narvik City N 68.26 E 17.25, an additional station will be built at Longyearbyen Svalbard and the ground stations will be added to the Federated Ground Network
Author, publisher and bookseller : a tripartite synergy in Nigerian book industry
No full textThis work is about the roles of Author, Publisher and Bookseller in Book development in
Nigeria. The paper started by delving into the history of Book Publishing in Nigeria after
which it proceeded by defining who an author, a publisher, and a bookseller is and
expatiated on the indispensable roles of these key actors in Nigerian Book Industry and in
the emerging Information Society. Furthermore, the various constraints to book
development were identified while the paper advised on how the Book Industry can be
further promoted in Nigeria. However, the paper concluded and made recommendations
on how the Book sector can help in enhancing scholarship in the country
Harnessing intellectual property for development : some thoughts on an appropriate theoretical framework
No full textIntellectual Property (IP) law is expected to provide equitable protection for eligible kinds of works in virtually all industries; to achieve fair treatment of creator, user and societal interests; and to contribute to a country's efforts to achieve economic development. This is a tall order and debates pertaining to IP law tend to be heated and heavily contested due to the tensions caused by these high expectations. In an effort to move such debates forward, this paper advances a nuanced framework through which contested IP issues may be resolved and upon which national IP policy and legislation may be based
[Report to Chief J. E. Curry, by an unknown author #2]
No full textReport to Chief J. E. Curry, by an unknown author. The report contains a list of officers who gave depositions to the United States Attorney
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