1,721,120 research outputs found
Regioselective Pummerer rearrangement in [2.2]paracyclophanes
No full textWe investigated and rationalized a synthetic pathway to [2.2]paracyclophanedienes, that exploits the combination of the Pummerer rearrangement on a dithiacyclophane with a photochemical sulfur extrusion step and a base-catalyzed elimination step. The synthetic pathway is very effective for the symmetric, prototypical [2.2]paracyclophanediene. In the case of an asymmetric precursor, bearing two aromatic units with differing electronic properties, mass spectrometry coupled with gas chromatography analysis suggests that the Pummerer rearrangement installs the acetate groups on the methylene carbon atoms neighboring the perfluoroaryl moiety. The rearrangement occurs with a high regioselectivity. Such an unexpected result may be useful in the design of sophisticated [2.2]paracyclophane architectures for applications in catalysis and electronics
Making Things is Making People: from Design for All to Design for Each
No full textThe term "revolution" denotes a sudden and radical change. If this revolution takes place
in a "crisis" period, which literally condenses both the concept of danger and opportunity, its result
becomes disruptive and unpredictable. Today, society is attending the beginning of a fourth
industrial revolution that is a consequence of the earlier computer-science one, made by portable
supercomputers, intelligent robots and increased brain capabilities through neurotechnology.
This revolution introduces the "Industry 4.0" term to describe how it will change the "value chain"
configuration, promoting the creation of "smart factories". This revolution does not only make the
factory intelligent, but it is also the origin of the vast movement makers. As Cris Ardersen tells us,
we are faced with a new paradigm of thought that eliminates the gap between invention and mass
production: "If I could do it, anyone can do it" (Ardersen, 2009).
Klaus Schwab, who recently theorized this Fourth Revolution (2016), is convinced that we are only
at the beginning of a transformation that radically modifies the way we live, work, relate, and even
question the meaning of "being human". At the same time, some other market’s leaders (as Toyota)
are pursuing "the art of making people" (hitozukuri), which for years have been the basis for an
innovative and effective solution.
The main issue of this paper concerns the contribution of design in defining and supporting the role
of man within these emerging scenarios, in particular on the impact this fourth revolution
determines on the quality of people’s life, by analysing the meaning of "taking care”.
The ease of customized production opens up a new scenario that allows thinking and producing
objects even for a single need or for a single person. Far from the mass production, in this new
vision take place the European project "OpenCare" (by Makerspace WeMake and City of Milan),
the project "Make to Care" (by Opendot) and the recent project "Second name: Huntington" (by
the national Huntington association with well-known Italian designers, Milanese fablabs, Cattaneo
laboratories - internationally recognized for genetic programming - and Triennale of Milan).
Starting from this experiences of social and productive innovation, we will try to understand the
potential of the revolution when it is design-oriented, design-driven, but also when it is designed to
propose new design objects that impact on the more fragile people's daily life, the quality of home
life
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
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
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
Solvent-free thiol-Ene/-Yne click reactions for the synthesis of alkoxysilyl telechelic poly(propylene oxide)s
No full textThiol-ene/−yne click reactions can be a versatile toolbox for the design and modification of polymers, enhancing functionality and providing opportunities for the development of innovative materials and applications. Here, we report a simple strategy to synthesize alkoxysilyl telechelic poly(propylene oxide)s (PPO)s: a) through a post-polymerization functionalization via Williamson reactions, commercial PPO is modified at the chain-end secondary alcohols with allyl or propargyl units, achieving >99% conversion; b) subsequent click reactions of (3-mercaptopropyl)trimethoxysilane (MPTMS), triggered by thermal and photochemical radical initiators, result in the incorporation of alkoxysilane groups on the polyether chain. Both thermal and photochemical thiol-ene/−yne click pathways are robust methodologies for preparing alkoxysilyl-modified PPOs in excellent yields (> 99%). Optimal conditions were identified as solvent-free, at 65 °C with 2,2′-azobis(2-methylpropionitrile) (AIBN) as the radical source. Detailed NMR analyses confirm the quantitative transformation of vinyl/propargyl functionalities in the resulting alkoxysilyl telechelic PPOs. Preliminary studies on the stability of alkoxysilyl end-groups are reported using 29Si NMR spectroscopy
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