1,721,083 research outputs found
Combinatorial benders cuts for assembly line balancing problems with setups
No full textThe classical assembly line balancing problem consists of assigning assembly work to workstations. In the presence of setup times that depend on the sequence of tasks assigned to each workstation, the problem becomes more complicated given that two interdependent problems, namely assignment and sequencing, must be solved simultaneously. The hierarchical nature of these two problems also suggest a natural decomposition of the problem. This paper adopts such an approach and describes an exact algorithm based on Benders decomposition to solve both simple and mixed-model assembly line balancing problems with setups. The algorithm is tested on a set of benchmark instances and numerically compared against a mixed-integer linear programming formulation of the problem solved using an off-the-shelf optimizer
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
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
TESTICULAR MORPHOLOGY AND SEMEN CHARACTERISTICS OF FRESH AND THAWED SEMEN IN BEAUTY RAT SNAKES (ELAPHE TAENIURA): A MODEL FOR PHYSIOLOGY AND SPERM CRYOPRESERVATION OF ENDANGERED COLUBRIDAE.
No full textSnake populations are facing a significant global decline, with 33% of reptiles being classified as endangered [1]. Assisted reproductive technologies have proven to be fundamental to create gametes banks for species conservation [2, 3]. However, research on sperm collection, characteristics, and cryopreservation in snakes is notably scarce [3]. Beauty rat snakes (Elaphe taenuria) are classified as vulnerable, meaning that this species is considered at risk of extinction, unless the circumstances that are threatening their survival and reproduction change. Moreover, these snakes can serve as a model for assisted reproductive technologies in endangered species belonging to the family of Colubridae. For this reason, we aimed to investigate male anatomical features and sperm characteristics of 18 adult Beauty rat snakes. For each animal both testis and vasa deferentia were collected and measured for weight (testis) and length (testis and vasa deferentia). Furthermore, we assessed the effects of two distinct cryopreservation methods on sperm collected post-mortem. The spermatozoa were retrieved by and float up from vasa deferentia. Specifically, each vas deferens was placed into a 15 mL Falcon tube containing 1 mL of HEPES-TALP solution and incubated at room temperature (22 ◦ C) in the dark for 30 min. When retrieval and sperm analyses were successful (N = 11), spermatozoa were diluted into either a single or double-step TEST-yolk semen extender, with a final glycerol concentration of 12%. The freezing process took place at - 0.3°C/min in 0.5 mL straws, that were subsequently stored in liquid nitrogen for one week, when post-thaw sperm quality was assessed. Statistical analysis was performed using R version 4.3.1 (Vienna, Austria) and significance was considered for P < 0.05. Normally distribution of data was analyzed with Shapiro Wilk Test (P< 0.05). The Wilcoxon sum rank test indicated that the left testicle was smaller (45.77 mm ± 3 vs 51.39 mm ± 3.83; p = 0.007), lighter (1.18 g ± 0.25 vs 1.50 g ± 0.32; p = 0.003), and had a shorter vas deferens (271.94 mm ± 14.68 vs 332.39 mm ± 18.19; p = 0.0002) compared to the right one. However, no significant variations in total sperm count were observed in-between sides (p > 0.05). The total sperm count demonstrated a positive correlation between the number of morphologically normal spermatozoa and the weight of the testicle (p = 0.04 and p = 0.01, respectively; Spearman’s rank correlation test). There was no significant difference in terms of motility and morphology between the two freezing protocols (p > 0.05; Mann-Whitney U test). In conclusion, the present study describes some important andrological features of Beauty rat snakes, including new protocols for post-mortem sperm collection and cryopreservation. Furthermore, these results provide a starting point for studies on male reproductive physiology in Colubridae, not only for future research on this species but also as a model for endangered reptiles.
[1] IUCN. 2022. The IUCN Red List of Threatened Species. Version 2022-2. https://www.iucnredlist.org. Accessed on [November 30th, 2023].
[2] Huijsmans T.E.R.G. Postmortem Collection of Gametes for the Conservation of Endangered Mammals: A Review of the Current State-of-the-Art. Animals: an open access journal from MDPI, 13(8), 1360, 2023.
[3] Sandfoss M.R. Cryopreservation of Sperm from an Endangered Snake with Tests of Post-Thaw
Incubation in Caffeine. Animals: an open access journal from MDPI, 12(14), 1824, 2022
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