1,720,962 research outputs found

    Respiratory sinus arrhythmia magnitude quantification as a potential marker of stress and pain in cows and sheep

    No full text
    Respiratory sinus arrhythmia (RSA) provides a quantitative evaluation of ‘vagal tone’ and may be used for pain and stress assessment in livestock. The aim was to quantify the magnitude of RSA in cows and sheep. In 7 cows and 4 sheep standing at rest we measured the 3-lead electrocardiogram (ECG) together with the pneumogram, to identify inspiration and expiration. For each breath, RSA was the difference in instantaneous heart rate (HR) between the inspiratory peak and the expiratory trough, in percent of mean HR. The resting breathing rates (28 ± 2 and 32 ± 5 breaths/min in cows and sheep, respectively) were about twice those expected for similar size non-ruminants, in conformity with previous reports. Both species had long-period (>15 s) HR fluctuations. The average values of RSA, 1.4 ± 0.2% in cows and 7.8 ± 3.1 in sheep, were lower than those previously computed by an identical approach in humans (12%), dogs (40%) and horses (9%). In conclusion, by breath-by-breath analysis of instantaneous HR we measured RSA in both cows and sheep. Results from the present study represent a preliminary step in assessing whether or not RSA could be used as a biomarker for stress or pain in ruminants

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Full text link
    The 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 link
    We 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

    Evaluation of intra- and inter-rater agreement on ultrasound measurements of dairy cow teats by operators with different experience levels

    No full text
    Ultrasound is a valuable, non-invasive technique. It allows for detailed examination, precise measurement, and effective monitoring of teats in dairy cows. This study aimed to evaluate the reliability of ultrasound measurements of teats in dairy cows, specifically focusing on intra- and inter-rater agreement between operators with different levels of experience. The study included 51 healthy Holstein cows, with two operators (experienced and inexperienced) performing measurements on ultrasound images obtained before and after milking. The parameters analyzed were teat-canal length (TCL), teat-end width (TEW), teat-wall thickness (TWT), and teat-cistern width (TCW). Differences in teat measurements before and after milking, as well as between operators, were assessed using the Wilcoxon Signed Rank test and the Mann-Whitney U test, respectively. Intra- and inter-rater agreement was calculated using the intra-class correlation coefficient (ICC). Statistical significance was set at p < 0.05. A total of 402 ultrasound images were analyzed. Significant differences were found in TCL, TWT, and TCW before and after milking, while TEW remained unaffected. Statistically significant differences in TWT and TCW were observed between the two operators, while TCL and TEW did not show significant differences. Intra-rater agreement for the experienced operator was excellent, and for the inexperienced operator, it was good. Inter-rater agreement ranged from good to excellent for most parameters, except for TWT, where it was poor. The study confirms that both milking and operator experience influence teat measurements. However, with proper training, ultrasonography can be a reliable tool for assessing udder health in dairy cows, supporting its use in field conditions

    Dispelling the Myths Behind First-author Citation Counts

    Full text link
    We 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

    Author Index

    No full text
    Nao informado

    Case–Control Study: Endogenous Procalcitonin and Protein Carbonylated Content as a Potential Biomarker of Subclinical Mastitis in Dairy Cows

    Full text link
    Procalcitonin (PCT) and protein carbonylated content (PCC) are promising biomarkers for bacterial infection and inflammation in veterinary medicine. This study examined plasma PCT and PCC levels in healthy cows (H) and cows with subclinical mastitis (SCM). A total of 130 cows (65 H and 65 SCM) were included in this study. Blood samples were collected, and plasma was frozen at −80 °C. PCT levels were determined using a bovine procalcitonin ELISA kit, while PCC was measured following the methodology of Levine et al. Statistical analysis revealed a significant difference in PCT levels between H (75.4 pg/mL) and SCM (107.3 pg/mL) cows (p < 0.001) and significantly lower concentrations of PCC in the SCM group (H: 0.102 nmol/mL/mg, SCM: 0.046 nmol/mL/mg; p < 0.001). The PCT cut-off value for distinguishing healthy and subclinical mastitis animals was >89.8 pg/mL (AUC 0.695), with a sensitivity of 66.2% and specificity of 69.2%. PCT showed potential value as a diagnostic tool to help in decision making for subclinical mastitis cases, while PCC requires further studies to investigate the trend of this biomarker during localized pathology

    Mammary cistern size during the dry period in healthy dairy cows: A preliminary study for an ultrasonographic evaluation

    Full text link
    We evaluated the udder cistern (UC) size during the dry period using ultrasound. Forty healthy quarters were evaluated in both the longitudinal and cross-section of the UC. Quarters were evaluated at the drying-off (T0) and 24 h later (T1), then regularly until the end of the dry period (T7–T58), during the colostrum production phase (TCPP) and at 7 days in milking (T7PP). The Spearman test was applied to find the correlation between the ultrasonographic UC size (UUCS) assessment and time. The Friedman test and Dunn’s test for multiple comparisons as a post-hoc test were performed to compare the forequarter and hindquarter cross-sections (FQCSs and HQCSs, respectively) and the forequarter and hindquarter longitudinal sections (FQLSs and HQLSs, respectively) at T0 vs. T58 vs. TCPP vs. T7PP. A total of 440 images were evaluated. A negative linear correlation between time and FQCS and FQLS (r = −0.95; p < 0.0004) and between time and HQCS and HQLS (r = −0.90; p < 0.002) was found. The UUCS decreased throughout the dry period, starting to increase at the beginning of the next lactation. Measuring the UUCS provides useful information for monitoring the dry period
    corecore