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İklim değişikliğinin biyoçeşitlilik üzerindeki etkileri: tür dağılım modelleme yaklaşımı ile dört bitki türü üzerine örnek olay incelemesi
No full textConservation strategies are mainly focused on species existing in an environment shaped by natural and anthropogenic pressures. Yet, evidence shows that climate is changing faster than ever and expected to continue to change in the near future, which can be devastating for plants with restricted ranges. Turkey harbors many endemic species that might be affected from these changes. However, available data is scarce and biased, complicating the anticipation of future changes. Aim of this study is to improve our understanding of endemic species distributions and forecasting effects of climate change via species distribution modelling (SDM). The study is based on two Anatolian (Crocus ancyrensis and Crataegus tanacetifolia) and two Ankara (Salvia aytachii and Centaurea tchihatcheffii) endemics. Independent presence and absence data (ranging between 19-68 and 38-61, respectively) for each species was collected through fieldwork in and around the Upper Sakarya Basin in 2008 and 2009. With the software Maxent, SDMs were performed by using 8 least correlated environmental features and random presence records (of which 25% were used for confusion matrix). SDMs for current distributions of C. ancyrensis, C. tchihatcheffii and C. tanacetifolia were reliable enough for future extrapolations despite errors originating from scale, non-equilibrium status and biotic interactions, respectively. The model for S. aytachii failed due to absence of limiting factor (soil type) in the model. Future projections of those three species modelled using CCCMA-CGCM2 and HADCM3 climate models indicated three possible responses to climate change: (1) Extinction, especially for habitat specialists; (2) Range expansion, especially for generalist species; and (3) Range contradiction, especially for Euro-Siberian mountainous species. Species modelling can be used to understand possible responses of plant species to climate change in Turkey. Modelling techniques should to be improved, however, especially by integrating other parameters such as biotic interactions and through a better understanding of uncertainties.Ph.D. - Doctoral Progra
Anadolu ve Kıbrıs bombus(bombus) terrestris(l.1758) toplumları arasında morfometrik ve genetik farklılaşmalar.
No full textFour microsatellite loci were used to investigate differentiation in Bombus terrestris, a bumblebee of interest for its high value crops pollination. Two bumblebee populations, one from Ankara (the capital of Turkey) and one from North Cyprus were analyzed. In these populations, the total number of alleles detected per polymorphic locus ranged from 7 to 12. FST genetic distance between Ankara and North Cyprus B. terrestris populations based on four microsatellite loci was calculated as 0,09351. This applies that there is significant (P<0,001) differentiation between Anatolian and Cypriot populations. Moreover, statistically significant differences between two populations were found in wing characters studied. According to the potential for local adaptation and individual fitness of bumblebees, microsatellite data calls for protection of Bombus terrestris populations against importation of bumblebees of foreign origin which are used as crop pollinator.M.S. - Master of Scienc
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
Artvin ve çevresinde çam kese böceği riskinin geleceğe yönelik modellenmesi
Get PDFIn recent decades, climate change has been receiving a lot of attention from researchers as it is believed to be proceeding at an extraordinary rate during the last 1,300 years and many studies have attempted to document and predict its environmental effects. Eastern winter pine processionary moth (PPM), Thaumetopoea wilkinsoni (Lepidoptera, Notodontidae), an economically important pest of pines in the Eastern Mediterranean Basin, distributed through almost all coastal regions within Turkey. Even though, its European sister species, T. pityocampa is known to be an aggressive invader under global warming in Europe and proved to expand its range towards northern latitudes; there is a lack of knowledge about species current and future status through Turkey, especially Artvin and adjacent regions (Eastern Black Sea Region) where it has not have much effect yet. In this study, we aimed to predict PPM’s current and future distribution through Artvin and adjacent regions by using Maximum Entropy Modeling (Maxent) software. We used 65 sampling points in conjunction with 7 climatic variables that were least intercorrelated and with greatest significant contribution to the distribution model. As the statistical tests showed that the fit of the generated model is good, we further carried on using this model for future predictions. Our results indicated that PPM would expand its range towards Artvin and adjacent regions. Even though, currently this region is not under risk of PPM invasion, models suggest that future climatic conditions might trigger PPM invasion in near future - by 2050 - 2080.Son 1.300 yılın en yüksek oranlarına ulaşan iklim değişimi son zamanlarda araştırmacıların ilgisini çekmekte ve çevresel etkilerini tahminleyen birçok araştırmaya konu olmaktadır. Çam kese böceği (ÇKB), Thaumetopoea wilkinsoni (Lepidoptera, Notodontidae), Doğu Akdeniz Havzası’ndaki çamlarda son derece önemli zararlara neden olan ve ülkemizde de neredeyse tüm sahil şeridini işgal etmiş bir güvedir. Avrupalı kardeş türü olan T. pityocampa’nın küresel ısınmanın etkisiyle yayılış alanına kuzey enlemlere doğru genişlettiği bilinmektedir. Ancak söz konusu türün Türkiye’deki mevcut ve gelecekteki durumu ile ilgili bilgilerimiz eksiktir. Bu çalışmada Türkiye’deki ÇKB populasyonlarının bugünkü ve gelecekti dağılımının Maksimum Entropi Modellemesi (Maxent) kullanılarak tahmin edilmesi amaçlanmıştır. 65 örnekleme noktası ve birbiriyle en az ilişkili ve dağılım modeline en çok katkı sağlayan 7 iklimsel değişken ile birlikte kullanılmıştır. İstatistiksel sınamalar oluşturulan modelin iyi bir şekilde uyum sağladığını gösterdiğinden, bu model gelecek tahminlemesinde kullanılmıştır. Modelimiz çam kese böceğinin dağılım alanını Türkiye’nin kuzeydoğusuna doğru genişleteceğini tahminlemiştir. Günümüzde iklimsel olarak ÇKB istila riski taşımayan Artvin ve civarı modele göre 2020 ve 2050 yıllarında ÇKB istilası için uygun hale gelecektir
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
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