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Species diversity of the malaria vector Anopheles Maculipennis group (Diptera: Culicidae) in Estonia
Full text linkBakalaureusetöö
Vee ja maismaa ökosüsteemide rakendusbioloogia õppekavalIga aastaselt haigestub maailmas malaariasse ligikaudu 219 miljonit inimest. Seda haigust
põhjustavaid algloomi levitavad ehk siirutavad hallasääsed (Anopheles (An.)). Nende
mitmekesisus ei ole suur ainult maailmas vaid ka Eestis. Malaaria patogeene levitavad ka
Anopheles maculipennis kompleksi kuuluvad krüptilised liigid. Käesoleva töö eesmärgiks
on välja uurida, milline on selle grupi mitmekesisus Eestis. Selleks kasutati Eestist püütud
hallasääski ning DNA eraldamist. Peale DNA eraldamist isendist tuli puhastada
sekveneeringud ja neist saadud tulemused said kirja pandud. Tulemused näitasid, et Eestis
on An. maculipennis kompleksi liikidest kõige levinum An. messae. See liik on ka
üleüldiselt Euroopas levinuim malaaria siirutaja. Kui teha suuremaid uuringud kuhu
kaasata rohkem püügikohti ja ka teised Eestis elavad hallasääsed, kes malaariat levitavad.
Täiendavate uuringutega saab ka teada, kui kaugele on võimeline see liik üldse edasi
levima.Every year, 219 million people fall ill with malaria. Although malaria is currently mostly
confined to the tropics and subtropics, it was also found in Estonia less than a century
ago. Malaria is caused by Plasmodium protozoa, that are distributed by anopheline
(Anopheles) mosquitoes, which is a large genus of mosquitoes made up of many species,
some of which can even be found in Estonia. Among others, malaria protozoa can also
be distributed by cryptic species belonging to the Anopheles (An.) maculipennis
complex. These species are called cryptic, because it is impossible to tell them apart
based on morphological characteristics alone. Estonia is known to be a home for at least
two such species: An. maculipennis and An. messae. Of these two, An. messae is a wellknown malaria pathogen distributer. The aim of this work was to find out how many of
the Estonian An. maculipennis complex mosquitoes are from the An. messae species.
Therefore, as many Estonian caught An. maculipennis complex insects as possible were
identified by molecular methods. Thus, these insects went through DNA extraction, the
samples were then replicated and the effectiveness of the replication was examined by
gel electrophoresis. Positive samples were sequenced by the Institute of Genomics Core
Facility of the University of Tartu. Sequences were then organised and compared to online databases. Results showed, that An. messae was by far the most numerous species
of its complex in Estonia. It is also the most common malaria vector in Europe. For
continuing research, it would be better to involve more mosquito catch sites and other
possible Estonian malaria carries
Comparative analysis of determination methods for soil reaction and development of conversion functions
No full textMagistritöö
Kalanduse ja rakendusökoloogia õppekavalMulla reaktsioon on oluline indikaator mulla kvaliteedi hindamiseks, ning üks tema tähtsamaid rolle on taimede abistamine toiteelementide omastamisel ja säilitamisel mullas. Liigse happesuse korral on taimede kas pärsitud. Sama on ka liigse aluselisuse korral. Selleks, et taimed saaks optimaalselt kasvada on vajalik määrata mulla happesus, mille määramiseks on mitu erinevat kaudset ja laboratoorset meetodit.
Käesoleva magistritöö eesmärk on võrrelda erinevate põllumuldade pH määramismeetodeid ning töötada välja teisenduse seosed nende kahe meetodi vahel. Töös kasutati 142 põllumulla proovi mis määrati kahes erinevas lahuses, KCl ja CaCl2. Tulemusena pH väärtused varieerusid vastavalt meetodile. KCl oli happelisem keskkond seega tulemused olid väiksemad kui CaCl2 lahuses määratuna. Lisaks tuli kahe määramismeetodite vähe suurem just happelistemate muldade puhul. Neutraal ja aluseliste muldade puhul on meetodite vahe peaaegu, et olematu. Tulevikus võiks suurema valimi kogusega teha mõõtmisi ka teise määramismeetodiga, milleks oleks deioniseeritud vesi.Soil reaction is an important indicator for assessing soil quality, and one of its most significant roles is assisting plants in the uptake and retention of nutrients in the soil. When there is excessive acidity, plant growth is inhibited. The same applies in the case of excessive alkalinity. To ensure optimal plant growth, it is necessary to determine the soil’s acidity, for which there are several indirect and laboratory-based methods.
The aim of this master's thesis is to compare different pH determination methods for agricultural soils and to develop conversion relationships between two of these methods. In this study, 142 agricultural soil samples were analyzed using two different solutions: KCl and CaCl₂. As a result, the pH values varied depending on the method used. KCl provided a more acidic environment, so the results were lower than those measured in the CaCl₂ solution. Additionally, the difference between the two methods was slightly greater for more acidic soils. For neutral and alkaline soils, the difference between the methods was almost negligible. In the future, with a larger sample size, it would be beneficial to also perform measurements using a third method—deionized water
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
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