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"Okapi."
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My tongue is long and curves
\"In this book, young readers will learn about okapi.\"-- Provided by publisher.
Book
The Forest Giraffe
\"In the Ituri tropical rainforest of central Africa lives a mammal with donkey-like ears and zebra-like striped legs and rump. This animal is the okapi. Despite its ears and stripes, the okapi isn't related to the donkey or zebra. Instead, its related to the giraffe!\" (ProQuest LLC) Read more about okapis.
Journal Article
Studies on Trueperella pyogenes isolated from an okapi
The present study was designed to characterize phenotypically and genotypically two Trueperella pyogenes strains isolated from an okapi (Okapia johnstoni) and a royal python (Python regius). Both strains could be clearly identified as T. pyogenes. The T. pyogenes strain isolated in high number from the vaginal discharge of an okapi seems to be of importance for the infectious process; the T. pyogenes strain from the royal python could be isolated from an apparently non-infectious process. However, both strains represent the first isolation of T. pyogenes from these animal species.
Journal Article
Design and analysis of microblog-based summarization system
A daily summary or digest from microblogs allows social media users to stay up to date on what happened today on their favorite topic. Summarizing microblogs is a non-trivial task. This paper presents a summarization system built over the Twitter stream to summarize the topic for a given duration. Tweet ranking is the primary task of designing a microblog-based summarization system. After ranking tweets, the selection of relevant tweets is the crucial task for any summarization system due to the massive volume of tweets in the Twitter stream. In addition, the summarization system should include novel tweets in the summary or digest. The measure of relevance is typically the similarity score obtained from different text similarity algorithms. These measure the similarity between user information needs and each tweet. The more similar, the higher the score. So we need to choose a threshold that can minimize false-positive judgments for this task. In this paper, we proposed novel threshold estimation methods to find optimal values for these thresholds and evaluate them against thresholds determined via grid search. These methods estimate the thresholds with reasonable accuracy, according to the results. Previous research has empirically and heuristically set these thresholds, and our work suggests a method that exploits statistical features of the ranking list to estimate these thresholds. We used language models to rank the tweets and to select relevant tweets. For any language model, the selection of the smoothing technique and its parameters are critical. The results are also compared with the standard probabilistic ranking algorithm BM25. Learning to rank strategies is also implemented, which shows substantial improvement in some of the result metrics. Experiments were performed on standard benchmarks like the TREC Microblog 2015, TREC RTS 2016, and TREC RTS 2017 datasets. Different variants of normal discounted cumulative gain, the standard official evaluation metric of TREC, nDCG-1, nDCG-0, and nDCG-p are used in this study. We also performed a comprehensive failure analysis on our experiments and identified key issues for improvement that can be addressed in the future.
Journal Article
REPEATED USE OF A THIAFENTANIL-BASED ANESTHESIA PROTOCOL IN AN OKAPI (OKAPIA JOHNSTONI)
Seven anesthesia events were performed over 6 wk on a 1.5-yr-old female okapi (Okapia johnstoni) being managed for a fetlock injury. A combination of butorphanol (B) (median; range) (0.045; 0.031–0.046 mg/kg), medetomidine (M) (0.037; 0.031–0.037 mg/kg), ketamine (K) (0.553; 0.536–1.071 mg/kg), and thiafentanil (T) (0.0045; 0.0040–0.0046 mg/kg) was administered in a padded stall. One dart containing all drugs was used for the first two anesthesias. Subsequently, BM was administered 10 min prior to KT using two darts. Time (median; range) from initial injection to first effects (6; 3–7 min) and recumbency (14; 4–20 min) were recorded. Induction quality with the one-dart protocol was poor or fair and was good or excellent with the two-dart protocol. Following recumbency, the okapi was intubated and ventilated, and physiological parameters were recorded. Anesthesia was consistently achieved with BMKT, but induction was smoother with the staged two-dart approach. Neither resedation nor renarcotization was observed post-reversal.
Journal Article
Giraffe Stature and Neck Elongation: Vigilance as an Evolutionary Mechanism
Giraffe (Giraffa camelopardalis), with their long neck and legs, are unique amongst mammals. How these features evolved is a matter of conjecture. The two leading ideas are the high browse and the sexual-selection hypotheses. While both explain many of the characteristics and the behaviour of giraffe, neither is fully supported by the available evidence. The extended viewing horizon afforded by increased height and a need to maintain horizon vigilance, as a mechanism favouring the evolution of increased height is reviewed. In giraffe, vigilance of predators whilst feeding and drinking are important survival factors, as is the ability to interact with immediate herd members, young and male suitors. The evidence regarding giraffe vigilance behaviour is sparse and suggests that over-vigilance has a negative cost, serving as a distraction to feeding. In woodland savannah, increased height allows giraffe to see further, allowing each giraffe to increase the distance between its neighbours while browsing. Increased height allows the giraffe to see the early approach of predators, as well as bull males. It is postulated that the wider panorama afforded by an increase in height and longer neck has improved survival via allowing giraffe to browse safely over wider areas, decreasing competition within groups and with other herbivores.
Journal Article
Evolutionary analysis of vision genes identifies potential drivers of visual differences between giraffe and okapi
The capacity of visually oriented species to perceive and respond to visual signal is integral to their evolutionary success. Giraffes are closely related to okapi, but the two species have broad range of phenotypic differences including their visual capacities. Vision studies rank giraffe's visual acuity higher than all other artiodactyls despite sharing similar vision ecological determinants with many of them. The extent to which the giraffe's unique visual capacity and its difference with okapi is reflected by changes in their vision genes is not understood.
The recent availability of giraffe and okapi genomes provided opportunity to identify giraffe and okapi vision genes. Multiple strategies were employed to identify thirty-six candidate mammalian vision genes in giraffe and okapi genomes. Quantification of selection pressure was performed by a combination of branch-site tests of positive selection and clade models of selection divergence through comparing giraffe and okapi vision genes and orthologous sequences from other mammals.
Signatures of selection were identified in key genes that could potentially underlie giraffe and okapi visual adaptations. Importantly, some genes that contribute to optical transparency of the eye and those that are critical in light signaling pathway were found to show signatures of adaptive evolution or selection divergence. Comparison between giraffe and other ruminants identifies significant selection divergence in
and
. Significant selection divergence was identified in
while positive selection was detected in
when okapi is compared with ruminants and other mammals. Sequence analysis of
showed that at least one of the sites known to affect spectral sensitivity of the red pigment is uniquely divergent between giraffe and other ruminants.
By taking a systemic approach to gene function in vision, the results provide the first molecular clues associated with giraffe and okapi vision adaptations. At least some of the genes that exhibit signature of selection may reflect adaptive response to differences in giraffe and okapi habitat. We hypothesize that requirement for long distance vision associated with predation and communication with conspecifics likely played an important role in the adaptive pressure on giraffe vision genes.
Journal Article
Non-invasive genetic identification confirms the presence of the Endangered okapi Okapia johnstoni south-west of the Congo River
The okapi Okapia johnstoni, a rainforest giraffid endemic to the Democratic Republic of Congo, was recategorized as Endangered on the IUCN Red List in 2013. Historical records and anecdotal reports suggest that a disjunct population of okapi may have occurred south-west of the Congo River but the current distribution and status of the okapi in this region are not well known. Here we describe the use of non-invasive genetic identification for this species and assess the success of species identification from dung in the wild, which varied throughout the range. This variation is probably attributable to varying okapi population densities and/or different sample collection strategies across the okapi's distribution. Okapi were confirmed to occur south-west of the Congo River, in scattered localities west of the Lomami River. We demonstrated that non-invasive genetic methods can provide information on the distribution of cryptic, uncommon species that is difficult to obtain by other methods. Further investigation is required to genetically characterize the okapi across its range and to investigate the biogeographical processes that have led to the observed distribution of okapi and other fauna in the region.
Journal Article