1,721,056 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
Effects of repeated investigator disturbance on corticosterone concentrations and the immune system in chicks of Black-Legged Kittiwake (Rissa tridactyla)
Full text linkRepeated exposure to investigator disturbance increases the corticosterone levels and can give detrimental effects on the growth and immune system in nestlings. As the offspring is developing, they need to invest in different life history components. Since the resources are limited, the investment has to be a trade-off between components like immune system and growth. The immunity is divided into the innate immune system with initial non-specific protection and the acquired immune system with specific pathogen protection. The acquired immune system is considered to be the more costly to develop.
The present study examined the effects of repeated investigator disturbance on the nestlings of the Black-Legged Kittiwakes during the nestling season at Svalbard. The objective was to test if repeated disturbance caused an increase in the baseline corticosterone levels, increased the heterophil to lymphocyte (H/L) ratio or altered the growth of the nestlings of the experimental group. Blood samples were taken of the experimental group and the control group at day 6 and 31 after hatching. The experimental nestlings were removed from their nests and the biometrics were measured every second day for 25 days, while the controls were only measured at day 6 and 31. The nestlings of the experimental group did not increase their baseline corticosterone levels or H/L ratio compared to the control group. There were also no significant differences on the body condition index (BCI) or the biometric measurement between the two groups either. The results of the present study suggest therefore that the nestlings of the Black-Legged Kittiwake are resilient to and do not perceive the investigator disturbance as a stressor.
A significant correlation between the H/L ratio and the body condition index (BCI) of the nestlings was found, proving a relationship between nestlings with low BCI having a high H/L ratio. Differences in H/L ratio between the sexes were also proven, with the females having a higher H/L ratio than the males. These results are consistent with previous studies
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
The effect of repeated handling on telomere dynamics, body condition, and short-term survival in chicks of the Black-legged Kittiwake (Rissa tridactyla)
No full textIn the present study, effects of investigator disturbance on chicks of the Black-legged Kittiwake were investigated by looking at telomere dynamics, growth, and short-term survival. An experiment group was exposed to a handling procedure every second day for 25 days, and compared to a control group. Although both experimental and control chicks showed a statistically significant reduction in total telomere length, no difference was detected between the two groups despite visual signs of stress in the experimental chicks. A hyporesponsive stress period is suggested as a possible explanation for the lack of differences between the two groups in the present study. Although all research on populations of wild animals should continue to be conscious of the impact of human presence on the studied animals both for welfare and scientific reasons, the results strongly suggest that chicks of the Black-legged Kittiwake are resistant to investigator disturbance during the nestling period.
In the present study, chicks from larger broods had longer telomeres at age 31 days than chicks without siblings. Differences in parental quality are suggested as a possible explanation for the observed relationship. Furthermore, a positive correlation was found between telomere length at first sampling body mass 25 days later, which is consisted with previous findings on the relationship between telomere length and fitness
The effect of repeated handling on telomere dynamics, body condition, and short-term survival in chicks of the Black-legged Kittiwake (Rissa tridactyla)
Full text linkIn the present study, effects of investigator disturbance on chicks of the Black-legged Kittiwake were investigated by looking at telomere dynamics, growth, and short-term survival. An experiment group was exposed to a handling procedure every second day for 25 days, and compared to a control group. Although both experimental and control chicks showed a statistically significant reduction in total telomere length, no difference was detected between the two groups despite visual signs of stress in the experimental chicks. A hyporesponsive stress period is suggested as a possible explanation for the lack of differences between the two groups in the present study. Although all research on populations of wild animals should continue to be conscious of the impact of human presence on the studied animals both for welfare and scientific reasons, the results strongly suggest that chicks of the Black-legged Kittiwake are resistant to investigator disturbance during the nestling period.
In the present study, chicks from larger broods had longer telomeres at age 31 days than chicks without siblings. Differences in parental quality are suggested as a possible explanation for the observed relationship. Furthermore, a positive correlation was found between telomere length at first sampling body mass 25 days later, which is consisted with previous findings on the relationship between telomere length and fitness
Effects of repeated investigator disturbance on corticosterone concentrations and the immune system in chicks of Black-Legged Kittiwake (Rissa tridactyla)
No full textRepeated exposure to investigator disturbance increases the corticosterone levels and can give detrimental effects on the growth and immune system in nestlings. As the offspring is developing, they need to invest in different life history components. Since the resources are limited, the investment has to be a trade-off between components like immune system and growth. The immunity is divided into the innate immune system with initial non-specific protection and the acquired immune system with specific pathogen protection. The acquired immune system is considered to be the more costly to develop.
The present study examined the effects of repeated investigator disturbance on the nestlings of the Black-Legged Kittiwakes during the nestling season at Svalbard. The objective was to test if repeated disturbance caused an increase in the baseline corticosterone levels, increased the heterophil to lymphocyte (H/L) ratio or altered the growth of the nestlings of the experimental group. Blood samples were taken of the experimental group and the control group at day 6 and 31 after hatching. The experimental nestlings were removed from their nests and the biometrics were measured every second day for 25 days, while the controls were only measured at day 6 and 31. The nestlings of the experimental group did not increase their baseline corticosterone levels or H/L ratio compared to the control group. There were also no significant differences on the body condition index (BCI) or the biometric measurement between the two groups either. The results of the present study suggest therefore that the nestlings of the Black-Legged Kittiwake are resilient to and do not perceive the investigator disturbance as a stressor.
A significant correlation between the H/L ratio and the body condition index (BCI) of the nestlings was found, proving a relationship between nestlings with low BCI having a high H/L ratio. Differences in H/L ratio between the sexes were also proven, with the females having a higher H/L ratio than the males. These results are consistent with previous studies
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
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