1,721,126 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Social-ecological dynamics at the livestock-wildlife interface in an African savanna
Get PDFAmidst the global biodiversity crisis, eastern and southern Africa’s rangelands stand out as one of the most critical regions for conservation attention. They contain much of the world’s biodiversity and some of the only intact large mammal assemblages.
However, over the next 50 years, these ecosystems will be disproportionally threatened by the global-scale impacts of land transformation and climate change. So far, the primary response to the global biodiversity crisis, both globally and within eastern and southern Africa, has been through an increase in the extent of protected areas (PAs). Yet, PA expansion has been unable to halt biodiversity
loss. This thesis explores the factors driving this negative ecological trajectory at the livestock-wildlife interface in Africa’s rangelands. First, I use a Kenyan case study to demonstrate that the current PA network inadequately represents biodiversity, indicating that conservation practice and policy need to extend across “working landscapes”, such as rangelands and agricultural areas, to prevent loss. Second, I create a metric to show, for the first time, that PAs in eastern and southern Africa are under immense pressure along their boundaries, threatening
their utility. Because of this, I argue that we must develop conservation strategies that cut across species and land-use boundaries to alleviate pressure on PAs and ensure that global biodiversity targets are met.
To understand how best to alleviate these pressures, I use a social-ecological systems (SES) lens to identify the drivers of biodiversity loss at the livestock-wildlife interface, using data collected across six ecosystems in southern Kenya. To do so, I compiled a wide variety of socio-economic and ecological data. This includes land price data collected from scraping websites, data from multiple sources of long-term changes in climate, rangeland productivity, and wildlife and livestock numbers, and the collation of data on ecosystem boundaries and land tenure. Specifically, I collected and synthesised one of the most extensive data sets on the status of any rangeland by mapping the extent of livestock enclosures, fencing, and agriculture across 35,000 km2 in southern Kenya.
My analysis of these data demonstrates how the profit-driven turnover of ownership, subdivision and transformation of land in southern Kenya is rapidly underway, fragmenting ecosystems, changing governance structures, and degrading rangelands. This process is causing widespread detrimental impacts to savanna biodiversity and the sustainability of the pastoral social-ecological system. Our comprehensive analysis exposes proximate anthropogenic stressors as overwhelmingly strong drivers of ecosystem-level change, currently eclipsing the impact of climate change, and confirms their importance for conservation within the rangelands of eastern and southern Africa. The lesson from southern Kenya is that African savannas can quickly flip from rain-driven to human-driven ecosystems. Thus, conservation solutions must focus on local drivers of change, which must be traced
back to the higher-level socio-economic and political developments to which they are responding. In the face of global change, it is evident that economic incentives, underwritten by devolved management and governance of rangelands and wildlife, will be vital for conservation in this region. Ensuring there is an instrumental value of wildlife for landowners and national governments is critical, allowing landholders to convert wildlife and biodiversity from a short-term liability into a
long-term asset. A landscape-based approach working across scales and sectors while incorporating and reacting to these SESs complexities is a critical step in addressing these shortcomings. I provide an example of this approach in southern Kenya, in what we term “inside-out” conservation. This broader perspective improves the chances that global biodiversity targets and sustainable development
goals are aligned. It also ensures that limited conservation resources are used to benefit both people and wildlife through PAs and in the larger, more functional landscapes in which they are embedded
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Collaborative Research: Ecological legacy effects of megacarcasses in African savanna ecosystems
Get PDFFeeding height stratification among African browsing ruminants
No full textThis study investigated the hypothesis that the use of different feeding levels in the vegetation promotes resource partitioning among browsing ungulate species in African savannas. Focal animal feeding observations, recorded on a real-time basis using a computerized data-capture system, were conducted on giraffe (Giraffa camelopardalis Linnaeus), kudu (Trageluphus strepsiceros Pallas), impala (Aepyceros melampus Lichtenstein) and steenbok (Raphicerus campestris Thunberg) in the central region of the Kruger National Park, South Africa. Although there was clear stratification in mean feeding heights among the four species throughout the seasonal cycle, there was considerable overlap in the feeding-height ranges of kudu, impala and steenbok. Hence, feeding-height stratification probably only separates giraffe from the other species. Giraffe bulls fed at a higher level in the vegetation than cows, often with head and neck extended vertically. It is suggested that bulls benefit in this by gaining access to nutritious new shoots in the upper canopy, but may suffer an increased predation cost due to reduced vigilance when in this posture
- …
