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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
Soil-crop modelling of ecosystem services in diversified and integrated crop-livestock systems for climate change adaptation and mitigation
No full textAgriculture faces immense challenges: it must meet the growing demand for food,
feed, fiber, and fuel while significantly reducing its environmental impact. This challenge
is further compounded by climate change, which increasingly threatens agricultural
systems. In turn, these systems contribute to climate change, creating a selfreinforcing
cycle. To address these challenges, various agroecological strategies are
being proposed within crop rotations. These strategies range from efficiency measures,
such as reducing nitrogen fertilization, to substitution approaches like no-till,
and more comprehensive redesign methods, including growing cover crops, diversifying
crop rotations, and integrating livestock.
However, significant uncertainties remain regarding the impacts of these levers. Their
effectiveness depends on various factors, including pedoclimatic conditions and agronomic contexts, with trade-offs and synergies emerging among the ecosystem services provided by agricultural systems. There is a lack of research that spans broad spatiotemporal scales, which addresses the limitations of studies confined to narrow sites or short timeframes, yet still maintains a detailed analysis of key concepts such as soil
health, stability, and resistance to climate change.
In this thesis, we investigate the impacts of such agroecological levers on a wide
spectrum of indicators, each linked to specific ecosystem services: provisioning services
(e.g., productivity, profitability, and the stability and resistance of yields to extreme
climatic events), supporting services (e.g., soil carbon sequestration and reduced
nitrate leaching), and regulating services (e.g., greenhouse gas emissions reduction).
Various crop rotations, differing in their use of agroecological levers, are analyzed
under a range of current and future pedoclimatic conditions, with different climate
change scenarios. This includes site-specific studies in Lonzée and Gembloux (Belgium)
and São Miguel (Brazil), as well as large-scale assessments covering millions
of hectares in Belgium and the U.S. Midwest. To do so, we base on simulations conducted
with two different process-based soil-crop models, STICS and SALUS, which
are calibrated and validated using a large number of field experiments.
Results show that, across all three Belgian, Brazilian and American contexts, crop
diversification and, to a further extent, integrated crop-livestock systems (ICLS) offer
strong opportunities to enhance climate change adaptation through greater stability
and resistance of agricultural productivity to extreme climatic events. They also allow
to mitigate negative environmental impacts such as nitrate leaching and greenhouse
gas emissions. Reducing nitrogen fertilization proved to be an effective strategy for
mitigating both factors, with a relatively small impact on productivity that varied depending on agronomic context and pedoclimatic conditions. While cover crops significantly enhanced soil carbon sequestration, the impact of ICLS varied by region.
In Belgium and Brazil, it led to a substantial increase in soil organic carbon (SOC),
whereas in the U.S. Midwest, maize monocultures showed the highest SOC gains due
to the combination of no-till practices and the accumulation of large amounts of crop
residues. In all contexts, ICLS benefits were maximized under moderate grazing intensities
which optimize the trade-off between maximizing carbon harvest by grazing
for cattle live weight gain and maximizing carbon returned to the soil.
This thesis also involved developing innovative methodologies for crop modelling
and comparative metrics. A novel approach was designed to explicitly calculate carbon
fluxes in cropping systems, including net ecosystem exchange, gross primary productivity,
and ecosystem respiration. It proved to be able to capture the influence of
environmental drivers of CO2 fluxes inter-seasonal variability from a diversified crop
rotation. Additionally, a methodology was adapted to simulate ICLS with grazing
cattle, modelling animals dry matter intake, live weight gain and the return of faeces
and urine. One key challenge was implementing an engineering method to spatially
scale crop models over large areas using a High-Performance Computer. Additionally,
calibrating and validating these models across vast regions required extensive field experiments with detailed agronomic management data and high-quality measurements
of yields and SOC. We found that simulating the effects of different tillage practices
on yields and SOC with STICS is feasible but requires detailed parameterization, particularly regarding soil bulk density. Lastly, we adapted a methodology to assess crop
rotation resistance to extreme wet and dry climatic events in a granular manner, using
a drought index to characterize these events.
This thesis, by exploring various scenarios of crop diversification and crop-livestock
integration, demonstrates how process-based soil-crop models can be utilized to assess
strategies for agroecological transition across efficiency, substitution, and redesign levels.
By integrating these models with innovative methodologies for designing cropping
systems, it becomes possible to explore tailored scenarios that support diverse human
diets while minimizing food and feed imports and exports. Furthermore, when coupled
with our novel approach to evaluating stability and resistance against extreme climate
events, soil-crop models serve as essential tools for assessing the potential of these
systems in adapting to and mitigating climate change.L’agriculture est confrontée à d’immenses défis : elle doit répondre à la demande
croissante en aliments, fourrages, fibres et bioénergies, tout en réduisant significativement son impact environnemental. Ce défi est amplifié par le changement climatique, qui menace de plus en plus les systèmes agricoles. Par ailleurs, ces mêmes systèmes contribuent au changement climatique, créant ainsi un cercle vicieux. Pour relever ces défis, différentes stratégies agroécologiques sont proposées dans les rotations culturales.
Ces stratégies vont des mesures d’efficacité, telles que la réduction de la fertilisation
azotée, aux approches de substitution comme le non-labour, en passant par des
méthodes de redesign plus complètes, incluant l’implantation de cultures de couverture,
la diversification des rotations et l’intégration de l’élevage.
Cependant, d’importantes incertitudes subsistent quant aux impacts de ces leviers.
Leur efficacité dépend de nombreux facteurs, notamment les conditions pédoclimatiques
et les contextes agronomiques, avec l’émergence de compromis et de synergies
entre les services écosystémiques fournis par les systèmes agricoles. Il existe un
manque d’études à larges échelles spatiales et temporelles qui dépassent les limites des
recherches menées sur des sites restreints ou sur des périodes courtes, tout en permettant
une analyse détaillée de concepts clés tels que la santé des sols, leur stabilité et
leur résistance au changement climatique.
Dans cette thèse, nous étudions les impacts de tels leviers agroécologiques sur un
large éventail d’indicateurs liés à des services écosystémiques spécifiques : les services
de production (productivité et rentabilité, ainsi que leur stabilité et résistance face
aux événements climatiques extrêmes), les services de soutien (stockage du carbone
dans les sols et réduction du lessivage des nitrates), et les services de régulation (réduction des émissions de gaz à effet de serre). Différentes rotations culturales, variant
dans leur utilisation des leviers agroécologiques, sont analysées sous divers contextes
pédoclimatiques actuels et futurs, à travers différents scénarios de changement climatique.
Cela inclut des études de sites spécifiques à Lonzée et Gembloux (Belgique) et
São Miguel (Brésil), ainsi que des évaluations à grande échelle couvrant des millions
d’hectares en Belgique et dans le Midwest des États-Unis. Pour cela, nous nous appuyons
sur des simulations réalisées avec deux modèles mécanistes sol-plante, STICS
et SALUS, calibrés et validés à l’aide d’un grand nombre d’expériences de terrain.
Les résultats montrent que, dans les trois contextes étudiés (Belgique, Brésil et
États-Unis), la diversification des cultures et, dans une plus large mesure, les systèmes
intégrés cultures-élevage (ICLS) offrent des opportunités majeures pour renforcer
l’adaptation au changement climatique grâce à une plus grande stabilité et résistance
de la productivité agricole face aux événements climatiques extrêmes. Ils
permettent également d’atténuer les impacts environnementaux négatifs, notamment
la lixiviation des nitrates et les émissions de gaz à effet de serre. La réduction de la
fertilisation azotée s’est révélée être une stratégie efficace pour atténuer ces deux facteurs, avec un impact relativement faible sur la productivité, qui dépend néanmoins du
contexte agronomique et des conditions pédoclimatiques. Tandis que les cultures de
couverture ont significativement augmenté la séquestration du carbone dans les sols,
l’effet des ICLS varie selon les régions. En Belgique et au Brésil, ils ont entraîné
une augmentation substantielle du carbone organique du sol (SOC), tandis que dans
le Midwest américain, les monocultures de maïs ont affiché les gains les plus élevés
en SOC, en raison de la combinaison du non-labour et de l’accumulation de grandes
quantités de résidus de culture. Dans tous les contextes, les bénéfices des ICLS étaient
maximisés sous des intensités de pâturage modérées, optimisant ainsi le compromis
entre la récolte de carbone par le pâturage pour la prise de poids du bétail et le retour
du carbone dans le sol.
Cette thèse a également impliqué le développement de méthodologies innovantes
pour la modélisation des cultures et la création de métriques comparatives. Une approche
novatrice a été développée pour calculer explicitement les flux de carbone dans
les systèmes agricoles, incluant la Net Ecosystem Exchange, la Gross Primary Productivity
et la Ecosystem Respiration. Cette approche a permis de capturer l’influence des
facteurs environnementaux sur la variabilité intersaisonnière des flux de CO2 dans une
rotation culturale diversifiée. De plus, une méthodologie a été adaptée pour simuler
les ICLS avec du bétail en pâturage, modélisant l’ingestion de matière sèche par les
animaux, leur prise de poids et le retour des excréments et de l’urine au sol. Un défi
majeur a été la mise en oeuvre d’une méthode d’ingénierie permettant de spatialiser les
modèles de culture sur de vastes territoires à l’aide d’un High Performance Computer.
En outre, le calibrage et la validation de ces modèles à grande échelle ont nécessité
un grand nombre d’expériences de terrain avec des données agronomiques détaillées
et des mesures précises des rendements et du SOC. Nous avons constaté que la simulation
des effets des pratiques de travail du sol sur les rendements et le SOC avec
STICS est réalisable, mais nécessite un paramétrage précis, notamment en ce qui concerne
la densité apparente du sol. Enfin, une méthodologie a été adaptée pour évaluer
de manière détaillée la résistance des rotations culturales aux événements climatiques
extrêmes, en utilisant un indice de sécheresse pour caractériser ces événements.
En explorant divers scénarios de diversification des cultures et d’intégration cultures-élevage, cette thèse démontre comment les modèles mécanistes sol-plante peuvent être
utilisés pour évaluer les stratégies de transition agroécologique à travers les niveaux
d’efficacité, de substitution et de redesign. En les intégrant à des méthodologies innovantes pour la conception des systèmes agricoles, il devient possible d’explorer des
scénarios adaptés à différents régimes alimentaires tout en minimisant les importations
et exportations de denrées destinées à l’alimentation humaine et animale. De
plus, lorsqu’ils sont couplés à notre approche novatrice d’évaluation de la stabilité et
de la résistance aux événements climatiques extrêmes, ces modèles constituent des
outils essentiels pour analyser le potentiel de ces systèmes en matière d’adaptation et
d’atténuation du changement climatique
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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