1,721,113 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Sewage sludge in Europe and in the UK: environmental impact and improved standards for recycling and recovery to land
No full textSewage treatment and sewage sludge (also called biosolids) represent a serious environmental issue that has affected modern society for the past century. In response to this, an increasing number of controls and resulting regulations have been introduced to avoid polluting our rivers and seas with pathogens, oxygen-demanding organic debris, potentially toxic elements (PTEs) and eutrophying nutrients. Over the past few decades, improved technology and more stringent regulations, driven in Europe by the increasingly precautionary European Community (EC) legislation, have worked together to achieve a net decrease of the amount of some of the pollutants, both through treatment of the wastewater and by cutting or forbidding the intake of contaminants at source. The growing importance of cleaning up wastewater before returning it to natural waters has led to (1) a vast increase of the quantity and the quality of the sludge resulting from the treatment of wastewater, with a greater amount of pollutants removed during the treatment process; (2) a greater effort towards the reuse and recycling of the sludge as opposed to disposal (e.g. landfilling, incineration). One of the consequences of this situation is a rising interest in using soils (agricultural or not) to address the latter through various applications. In fact, as the sludge has to be disposed off safely, soils can be used as a system of assimilating, recycling or disposing off the sewage sludge. Science and legislation are trying to provide the safest possible route to accomplish these targets, but the subject is not free from controversy, often causing hot debates between the interested parties. This chapter aims to review the improved standards achieved with sewage sludge, touching in particular the British experience in the field of regulating the disposal and reuse of these materials
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
Genetic diversity at three palindromic sequences of the human Y chromosome
No full textOne of the most striking structural features of the male specific region of the human Y
chromosome (MSY) is the presence, within the ampliconic sequences, of eight massive
palindromes (P1-P8). Each palindrome is composed of two large inverted repeats (arms)
separated by a small “spacer” sequence at the centre. These elements, ranging from 30 kb
to 2.9 Mb, contain many testis-specific genes and typically exhibit > 99.9% intra-palindromic
(arm-to-arm) sequence identity. It has been hypothesized that the high observed sequence
similarity is due to abundant gene conversion events between the arms of each palindrome.
Although the occurrence of arm-to-arm gene conversion has been clearly demonstrated,
the effect of this molecular mechanism on the genetic diversity of palindromes, as well as
its rate and extension, remain largely unexplored. To gain new insights into the evolutionary
history of the human Y chromosome palindromic sequences and to shed light into the
dynamics of intra-palindrome gene conversion, we analysed by high-coverage next-
generation sequencing (50x) the shortest known palindromes (P6, P7 and P8) and their
relative spacers (for a total of about 0.3 Mb) in 158 samples chosen to represent most of the
independent evolutionary lineages (haplogroups) of the MSY. By this analysis we identified
several gene conversion events and a peculiar mutational pattern of the palindrome arms
with respect to the spacer. Moreover, we found few phylogenetically conserved paralogous
sequence variants (PSVs), suggestive of a high arm-to-arm gene conversion activity.
Because Y chromosomes are clonally inherited from father to son, it has been possible
to capture their evolutionary relationships in a robust phylogenetic tree with known age
of each node. By mapping gene conversion events across a Y tree based on thousands
of stable mutations obtained from 3.3 Mb of single copy MSY sequences, we were able to
calculate a precise Y-Y gene conversion rate for each of the palindromes here analysed
Decomposition of carboxymethyl cellulose based on nano-knife principle
No full textThe traditional degradation of organic pollutants is based on the sacrifice of chemical or biological reagents. In this study, a purely physical technique was developed to break the chemical bonds and consequently decompose macromolecules in aqueous solution. Assisted with a high-speed mechanical blade, refined quartz sand grains with particularly sharp nano-scale edges can act as 'nano-knives', which are able to cut the long chain of carboxymethyl cellulose (CMC, as a model molecule). High performance size exclusion chromatography measurements evidenced that the original CMC molecules (41,000 Da) were decomposed into a series of smaller molecules (460, 1000, 2200, 21,000, 27,000 and 31,000 Da). Consequently, the initial viscosity of the CMC solution (2 g/L) rapidly decreased by approximately 50% after 3 min treatment by the nano-knife materials along with the mechanical blade. Fourier transform infrared (FTIR) spectra indicated that the original functional groups were still present and new functional groups were not produced after shearing. The intensity of the main functional group beta-1-4-glycosidic bond (wavenumber 1062 cm(-1)) was observed to markedly decrease after shearing. These results indicated that the long-chain CMC was cleaved into short-chain CMC. A degradation mechanism was proposed whereby the cutting force generated by the rapid motion of the nano-knives may be responsible for the breakage of beta-1-4-glycosidic bonds in the macromolecular cellulose backbone. These results provide support for a potentially more affordable and environment-friendly strategy for physical-based decomposition of recalcitrant organic pollutants from aqueous solution without the need of chemical or biological reagents. (C) 2018 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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