1,720,954 research outputs found
Species composition and abundance of the spider fauna of the Hillside Dams Conservancy, Bulawayo. Zimbabwe.
No full textThe objective of the study was to describe the spider species composition and abundance of a semi arid protected area in Zimbabwe, the Hillside Dams Conservancy. The paper aims to introduce a neglected group of invertebrates -the arachnids which is primarily unknown to science particularly in Zimbabwe. Spiders were collected in ten weekly sessions from last week of July to September 2012, using sweep nets and beating trays. A total of 663 individuals belonging to 28 species distributed among 11 families were found in the conservancy. The Oxyopidae was the most abundant (n = 230) representing 35% of all spiders sampled, followed by Philodromidae (n = 140) with 21%, Thomisidae (n = 124) with 19%, and Salticidae (n = 87) with 13%. The most abundant species was an Oxyopidae Oxyopes sp (n = 186) representing 28% of the total, followed by a Philodromidae Philodromus sp (n = 120) with 18.1%, a Salticidae Salticidae sp (n = 82) with 12.4%. The Thomisidae was the most species rich family with twelve species, followed by Philodromidae with four species and the Oxyopidae with three species. Observed spiders belonged to five functional groups: stalkers, foliage wanderers, ambushers, orb weavers and ground wanderers in the ratio of 3: 3: 6:2:1 with regards to species richness. Spider diversity in protected areas in Zimbabwe is not yet well known despite their usefulness as indicators of the overall species richness and status of ecosystems, therefore this study sought to fill the existing void of Arachnology literature for the state and apprise future investigators of the spider fauna of Zimbabwe
Spider ecology in southwestern Zimbabwe, with emphasis on the impact of holistic planned grazing practices
No full textThe current information on Zimbabwean spiders is fairly poor and is mostly restricted to taxonomic descriptions, while their ecology remains largely unknown. While taxonomic studies are very important, as many species are becoming extinct before they are described, a focus on the ecology of spiders is also essential, as it helps with addressing vital questions such as the effect of anthropogenic activities on spider fauna. Therefore, in order to address this research gap, assessment of the response of spiders to holistic management practises within Debshan Ranch, Shangani, Zimbabwe was done. Additionally, in order to establish baseline data on spider fauna, the standardised South African National Survey of Arachnida sampling protocol was utilised to assess its efficacy within the Khami World Heritage Site. Spider sampling was done in three sub-projects: the first included sampling in several geographic distances around previously kraaled inclusions and control sites within the ranch, using sweep nets and pitfall traps, in six sampling periods from July 2017 until April 2018; the second included sampling that was done inside the previously kraaled inclusions and their surrounding areas dating back to at least ten months since cattle occupation in two sampling intervals early summer (November 2017) and late summer (March 2018), using pitfall traps; the third entailed sampling within Khami in three sampling periods (summer, winter and spring 2018) using six sampling methods, namely pitfall traps, beating sheets, litter sifting, sweeping, day hand collecting and night hand collecting. The model that best explained changes in mean grass height (cm), as well as percentage grass cover around previously kraaled inclusions and the control sites, was that which included time since kraal removal, whereas inside the inclusions and their surroundings was that which included season and short duration kraaling. At the functional group level, only the web builder‟s genera richness responded negatively to short duration kraaling around the previously kraaled inclusions and their control sites. On the other hand, inside the previously kraaled inclusions and their surroundings only ground dwelling abundance responded negatively and significantly to short duration kraaling. The most important predictor amongst the vegetation structure variables around the previously kraaled inclusions and control sites was mean grass height (cm), which impacted genera richness and abundance of both ground dwellers and web builders. In contrast, genera richness and abundance of plant wanderers were positively associated with mean grass height (cm). However, inside the previously kraaled inclusions and their surroundings the most important predictor was time since kraal removal and the vegetation structure variable percentage coarse woody debris cover, which responded positively to the ground dwellers. In addition, the late sampling season had significantly lower ground dwelling abundance compared to the early sampling season. Within the Khami World Heritage Site the riparian woodland had the highest species richness compared to the other biotopes. Similarly, the summer period also produced the highest diversity, with winter recording the lowest species richness. Night and day hand collecting had the highest observed species richness with adult individuals. In order to sample 50% of the spider assemblages, 15 samples were required to be collected in the mixed woodland, which represented the biotope requiring the fewest samples. Seasonality effects explained a significant amount of variation in changes of mean grass height (cm) and percentage cover around previously kraaled sites and their control sites. However, when inter-seasonal variation was excluded by sampling previously kraaled sites within one season, short duration kraaling explained a significant amount of variation. Standardised sampling protocols aid in establishing databases of spider fauna which will in the long run ensure inclusion of spiders in biodiversity reports in Zimbabwe, which has historically not been the case, due to limited information.University of the Free StateDeBeers Oppenheimer GroupDr Duncan McFadde
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
