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Tanakia is a bitterling genus with six species found in Far East Asia. Our aim was to construct the standard DNA barcode database available for the identification of six Tanakia species by comparing the range of intra- and inter-specific genetic distances, identifying the phylogenetic placement of each Tanakia species and providing the unique barcode characteristics that are specific to each species, using cytochrome oxidase I (COI) and cytochrome b (cyt b). Both loci failed to create a perfect barcoding gap between the ranges of inter- and intra-specific genetic distances, though interspecific COI distances were sufficiently greater than intraspecific values with only a few exceptions. In our phylogenetic analyses, T. koreensis and T. signifer did not form a monophyletic cluster of haplotypes in both loci. COI provided clear nucleotide characteristics that distinguish each species, whereas relatively fewer informative sites were found within the range of cyt b. Overall, COI could be regarded as appropriate species identification solution in Tanakia. Our analyses yielded some taxonomic issues that need the further investigation, and are expected to be helpful in the examination for the conservation status of Tanakia species that are on the verge of being endangered. [ABSTRACT FROM AUTHOR]

Endemic species typically have a narrow niche breadth, and are likely more vulnerable to extinction than more widespread taxa.Squalidus multimaculatusis a small cyprinid endemic to the Korean Peninsula, and its reported geographical range was restricted to several small rivers located along the southeast coast. Several populations ofS. multimaculatushave supposedly been subject to a variety of recent anthropogenic actions. Here, we analyzed the pattern of genetic diversity within and among populations ofS. multimaculatususing nine microsatellite loci to quantify the relative contributions of human-mediated processes to the contemporary distribution and genetic structure. Overall, low levels of genetic diversity were exhibited in the populations ofS. multimaculatus. Genetic differentiations among populations were not completely represented by their geographical proximity, likely resulting from the low intrapopulation genetic variability and anthropogenic transplants. The most conspicuous outcome of the anthropogenic activities was the introgression of alleles from a closely related species,S. gracilis majimae. Our study showed that anthropogenic transplanting, even with only a small number of individuals, can challenge our conservation goal to maintain the species integrity that has long been shaped in evolutionary processes. [ABSTRACT FROM AUTHOR]

This paper presents a system of large-scale language model adaptation for daily generated big-size text corpus using MapReduce in a cloud environment. Our large-scale trigram language model, consisting of 800 million trigram counts, was successfully implemented by a new approach using a representative cloud service (Amazon EC2), and a representative distributed processing framework (Hadoop). The ultimate goal of our research is to find the optimal number of Amazon EC2 instances in the LM adaptation under the time constraint that the daily-generated Twitter texts should be processed within 1 day. Trigram count extraction and model update for language model adaptation were performed for 200 million daily-generated Twitter texts. For trigram count extraction, we found that fewer than 3 h are required to process daily-generated Twitter texts when the number of instances is six. For model update, it was shown that fewer than 20 h are required to perform the model update when the number of instances is 10. Therefore, language model adaptation for daily generated 200 million Twitter texts can be successfully adapted within 24 h using at least 10 instances in Amazon EC2. [ABSTRACT FROM AUTHOR]

Geographic isolation and colonization events have been considered complimentary historical processes in shaping the contemporary structure of regional biotas and taxonomic diversity. Accordingly, insight regarding vicariance and geodispersal might be gained by the analysis of phylogenetic pattern of related but geographically isolated taxa. Here, we examined endangeredRhodeus pseudosericeusin the Korean Peninsula based on mitochondrial cytochromebsequences to provide information regarding the evolutionary origin of Amur-European bitterlings,Rhodeus sericeusandRhodeus amarus. Our data and the contemporary distribution ofR. pseudosericeusindicate that founding individuals have colonized the western coast of the Korean Peninsula via the paleo-Huang He River and since been subdivided into populations isolated by drainage formation. Our phylogenetic analyses indicated that it was likelyR. pseudosericeushad a sister relationship to theR. sericeus–amaruscomplex, indicating that theR. sericeus–amarusclade originated from the dispersal of eitherR. pseudosericeusor its ancestral lineage. The geodispersal scenario based on our phylogenetic analyses supports the previous hypothesis that the Amur River likely created confluences with some tributaries of the paleo-Huang He River. Overall, the present study offers new insight into the taxonomic entity ofR. pseudosericeusand a more comprehensive understanding of the phylogeographic history ofR. sericeusand European bitterling lineages. [ABSTRACT FROM PUBLISHER]

In the present paper, we make a first report on the complete mitochondrial DNA genome of Leptaulax koreanus, a Korean endemic species, in Passalidae. The mitogenome is 18,730 base pairs with 13 protein-coding genes, 22 tRNAs, 2 rRNAs, and a 4240 bp long AT-rich region. The overall base composition is 78.4% AT and 21.6% GC. The maximum likelihood analysis suggested that L. koreanus is a sister to other Scarabaeoidea species. [ABSTRACT FROM AUTHOR]