1,720,975 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
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
Little Penguins (Eudyptula minor) and Human Disturbance
Full text linkPenguins are a much-loved taxon, and are frequently the subject of both scientific research and tourist visitation. Many species of penguin do not show a behavioural response to human presence, so it is often assumed that the penguins are not negatively affected. However, in the absence of a visible behavioural response, physiological changes such as increases in heart rate may use up vital energy resources and lead to population-level consequences. The personality of individual penguins may also affect how they react to human disturbance.
There are an increasing number of commercial operations taking advantage of the apparent indifference of Little Penguins (Eudyptula minor) to human presence, such as the Oamaru Blue Penguin Colony at Oamaru, New Zealand. My study aimed to quantify the effects of human disturbance on Little Penguins. I recorded the heart rate (HR) of Little Penguins at Oamaru using artificial eggs, to measure responses to typical researcher and visitor interactions with penguins. Researcher interactions were: human speech, band checking, and weighing, and a penguin call playback was used as a control. I calculated the amount of energy expended by a Little Penguin in response to an invasive researcher interaction, i.e. weighing. HR responses to researcher interactions were compared with corticosterone responses obtained from the same individual penguins. I used chick mass data to compare chick growth and fledging weights between a colony visited by tourists and a control colony.
Little Penguins at Oamaru had stronger HR responses to being weighed than to hearing penguin calls or human speech. However, some individual penguins reacted as strongly or more strongly to having their band checked than to being weighed. There was some correlation between HR responses and corticosterone responses, suggesting that individual penguins respond consistently on a shy-bold personality continuum. The HR of incubating penguins averaged over four-hour periods did not differ significantly between a colony visited by tourists and a control colony. However, female penguins in the ‘medium disturbance’ zone of the visited colony had significantly higher resting heart rate (RHR) than their male counterparts. The amount of energy used by a Little Penguin in response to being weighed was found to be negligible. Chick fledging weights at the visited colony were significantly lower than those at the control colony, which may affect their first-year survival.
A balance must be reached between humans having close contact with wildlife, for purposes of research and education, and leaving the wildlife to itself. At Oamaru, current management practices are successful in facilitating the penguin colony’s growth while also permitting thousands of visitors to view the penguins every year. Future research focusing on individual penguins and the responses of particular personality types to environmental changes, including human disturbances, will aid the ongoing success of this colony
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
Assessing the impact of human disturbance on penguins
Full text linkxix, 257 p. : ill. (some col.) ; 30 cm.Nature conservation places great hopes on ecotourism, yet despite increasing pressure on the Earth's last wild areas, there is insufficient knowledge about human disturbance impact, and hence, visitor management must often remain inadequate. Penguins are an important tourism attraction. Lack of overt behavioural responses to human proximity at breeding sites has led to the common public misconception that penguins would be little affected by human visitation. However, even a single one-off disturbance or a series of low-key disturbances can have far-reaching impacts that are often not immediately discernable to the people involved.
I studied behavioural and physiological stress responses of three penguin species that according to anecdotal evidence respond very differently to human proximity. While behaviour could give an indication of the relative severity of a disturbance stimulus, measuring physiological responses was a more objective and powerful tool to quantify stress in all three species studied. As accumulating effects of human disturbance may affect breeding populations, I also monitored a range of reproductive parameters at sites that provided similar breeding habitat and overlapping foraging grounds yet were exposed to different levels of human visitation.
Human disturbance can be interpreted as perceived predation risk. Similar to antipredator responses, reaction to disturbance stimuli can affect individual fitness via energetic and lost opportunity costs of risk avoidance. I demonstrated that human proximity is energetically costly for penguins and more so than most stimuli that naturally occur at their breeding sites. Yet the severity of the same disturbance stimulus is perceived differently between species, populations and even individuals.
Snares penguins, Eudyptes robustus, appear to be little affected by human activity outside their immediate breeding colony. In comparison, Humboldt penguins, Spheniscus humboldti, proved to be very sensitive to human disturbance. They responded to a person visible at more than 150 m distance from their nest and needed up to half an hour to recover from even careful human approach. Nest densities were lower and breeding success was significantly reduced at more frequently visited sites.
In Yellow-eyed penguins, Megadyptes antipodes, I found elevated hormonal and heart rate responses at sites exposed to unregulated visitor access associated with reduced breeding success and lower fledgling weights, which result in reduced first-year survival and recruitment probabilities. Contrary to my expectations, birds that continued to breed despite frequent disturbance had not habituated to human proximity but appeared to be sensitised and responded more strongly to human disturbance. Hence, tourist-exposed penguins were not only disturbed more often, each disturbance event was more costly for the affected birds, eventually leading to poorer breeding performance.
Both initial stress response and habituation potential of Yellow-eyed penguins depended on sex, character and previous experiences with humans, and the observed individual differences in behavioural and physiological stress responses related to fitness parameters. Birds characterised as "frozen" were apparently best able to cope in human-disturbed habitats. Thus, human disturbance may drive contemporary evolutionary change in the composition of breeding populations with as yet unrealised consequences for conservation.
I give a detailed account of the current understanding of human disturbance related effects on penguins and list future research needs. Complex secondary effects of human disturbance and multiple stressor interactions are still little understood and require longterm population studies that enable us to disentangle human disturbance effects from environmental variability. Similarly, we still know very little about what factors drive habituation or sensitisation in wild populations, thus habituation to even apparently minor human disturbance cannot be assumed.
Subtle costs of what we think is minor disturbance can accumulate and may ultimately lead to lower nest numbers, poorer breeding success or reduced fledgling weights in more frequently visited penguin breeding areas. As the growth of nature-based tourism is expected to continue, it is important not only for ecological but also for economic sustainability to minimise any associated negative human impacts. It is clear that generic guidelines for managing human visitation of penguin colonies cannot be applied. Only rigorous research can provide the basis for appropriate site- and species-specific visitor management decisions.
I hope this study can provide a framework for better understanding human disturbance effects on penguins and maybe even on wildlife in general
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