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Ecological Guild Evolution and the Discovery of the World's Smallest Vertebrate  [PDF]
Eric N. Rittmeyer, Allen Allison, Michael C. Gründler, Derrick K. Thompson, Christopher C. Austin
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0029797
Abstract: Living vertebrates vary drastically in body size, yet few taxa reach the extremely minute size of some frogs and teleost fish. Here we describe two new species of diminutive terrestrial frogs from the megadiverse hotspot island of New Guinea, one of which represents the smallest known vertebrate species, attaining an average body size of only 7.7 mm. Both new species are members of the recently described genus Paedophryne, the four species of which are all among the ten smallest known frog species, making Paedophryne the most diminutive genus of anurans. This discovery highlights intriguing ecological similarities among the numerous independent origins of diminutive anurans, suggesting that minute frogs are not mere oddities, but represent a previously unrecognized ecological guild.
Discovery and Characterization of Distinct Simian Pegiviruses in Three Wild African Old World Monkey Species  [PDF]
Samuel D. Sibley, Michael Lauck, Adam L. Bailey, David Hyeroba, Alex Tumukunde, Geoffrey Weny, Colin A. Chapman, David H. O’Connor, Tony L. Goldberg, Thomas C. Friedrich
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0098569
Abstract: Within the Flaviviridae, the recently designated genus Pegivirus has expanded greatly due to new discoveries in bats, horses, and rodents. Here we report the discovery and characterization of three simian pegiviruses (SPgV) that resemble human pegivirus (HPgV) and infect red colobus monkeys (Procolobus tephrosceles), red-tailed guenons (Cercopithecus ascanius) and an olive baboon (Papio anubis). We have designated these viruses SPgVkrc, SPgVkrtg and SPgVkbab, reflecting their host species’ common names, which include reference to their location of origin in Kibale National Park, Uganda. SPgVkrc and SPgVkrtg were detected in 47% (28/60) of red colobus and 42% (5/12) red-tailed guenons, respectively, while SPgVkbab infection was observed in 1 of 23 olive baboons tested. Infections were not associated with any apparent disease, despite the generally high viral loads observed for each variant. These viruses were monophyletic and equally divergent from HPgV and pegiviruses previously identified in chimpanzees (SPgVcpz). Overall, the high degree of conservation of genetic features among the novel SPgVs, HPgV and SPgVcpz suggests conservation of function among these closely related viruses. Our study describes the first primate pegiviruses detected in Old World monkeys, expanding the known genetic diversity and host range of pegiviruses and providing insight into the natural history of this genus.
Rivaling the World's Smallest Reptiles: Discovery of Miniaturized and Microendemic New Species of Leaf Chameleons (Brookesia) from Northern Madagascar  [PDF]
Frank Glaw, J?rn K?hler, Ted M. Townsend, Miguel Vences
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0031314
Abstract: Background One clade of Malagasy leaf chameleons, the Brookesia minima group, is known to contain species that rank among the smallest amniotes in the world. We report on a previously unrecognized radiation of these miniaturized lizards comprising four new species described herein. Methodology/Principal Findings The newly discovered species appear to be restricted to single, mostly karstic, localities in extreme northern Madagascar: Brookesia confidens sp. n. from Ankarana, B. desperata sp. n. from Forêt d'Ambre, B. micra sp. n. from the islet Nosy Hara, and B. tristis sp. n. from Montagne des Fran?ais. Molecular phylogenetic analyses based on one mitochondrial and two nuclear genes of all nominal species in the B. minima group congruently support that the four new species, together with B. tuberculata from Montagne d'Ambre in northern Madagascar, form a strongly supported clade. This suggests that these species have diversified in geographical proximity in this small area. All species of the B. minima group, including the four newly described ones, are characterized by very deep genetic divergences of 18–32% in the ND2 gene and >6% in the 16S rRNA gene. Despite superficial similarities among all species of this group, their status as separate evolutionary lineages is also supported by moderate to strong differences in external morphology, and by clear differences in hemipenis structure. Conclusion/Significance The newly discovered dwarf chameleon species represent striking cases of miniaturization and microendemism and suggest the possibility of a range size-body size relationship in Malagasy reptiles. The newly described Brookesia micra reaches a maximum snout-vent length in males of 16 mm, and its total length in both sexes is less than 30 mm, ranking it among the smallest amniote vertebrates in the world. With a distribution limited to a very small islet, this species may represent an extreme case of island dwarfism.
Real Time Discovery of Dense Clusters in Highly Dynamic Graphs: Identifying Real World Events in Highly Dynamic Environments  [PDF]
Manoj K Agarwal,Krithi Ramamritham,Manish Bhide
Computer Science , 2012,
Abstract: Due to their real time nature, microblog streams are a rich source of dynamic information, for example, about emerging events. Existing techniques for discovering such events from a microblog stream in real time (such as Twitter trending topics), have several lacunae when used for discovering emerging events; extant graph based event detection techniques are not practical in microblog settings due to their complexity; and conventional techniques, which have been developed for blogs, web-pages, etc., involving the use of keyword search, are only useful for finding information about known events. Hence, in this paper, we present techniques to discover events that are unraveling in microblog message streams in real time so that such events can be reported as soon as they occur. We model the problem as discovering dense clusters in highly dynamic graphs. Despite many recent advances in graph analysis, ours is the first technique to identify dense clusters in massive and highly dynamic graphs in real time. Given the characteristics of microblog streams, in order to find clusters without missing any events, we propose and exploit a novel graph property which we call short-cycle property. Our algorithms find these clusters efficiently in spite of rapid changes to the microblog streams. Further we present a novel ranking function to identify the important events. Besides proving the correctness of our algorithms we show their practical utility by evaluating them using real world microblog data. These demonstrate our technique's ability to discover, with high precision and recall, emerging events in high intensity data streams in real time. Many recent web applications create data which can be represented as massive dynamic graphs. Our technique can be easily extended to discover, in real time, interesting patterns in such graphs.
Discovery: The Information Literate WorldCat  [cached]
Earl Givens
Kansas Library Association College and University Libraries Section Proceedings , 2013,
Abstract: Locating, synthesizing, and evaluating information is the heartbeat of information literacy. Using a high-powered discovery layer can assist in the mission of information literacy. However, in order for this partnership to come to fruition, traditional teaching practices must be re-examined to accommodate new technologies. This paper will define discovery, explore instructional practices, and investigate emerging teaching practices concerning the integration of information literacy instruction with discovery layers. The author of this article will use WorldCat local as the primary discovery layer for this study. As defined by the Online Computer Library Center (OCLC), WorldCat Local is a “webscale discovery solution that delivers single-search-box access to more than 1.071 billion items from your library and the world's library collections.” William Allen White Library at Emporia State University adopted WorldCat Local as its discovery solution after reviewing several discovery layers services. WorldCat Local was selected due to it continually evolving nature when dealing with the electronic resources and physical collection.
On the possible discovery of precessional effects in ancient astronomy  [PDF]
Giulio Magli
Physics , 2004,
Abstract: The possible discovery of astronomical effects due to precession - such as the shift in the declination of heliacal raising of bright stars or the precession of the equinoxes - is reviewed for various ancient cultures in the world. Although definitive evidence of the discovery is still lacking, the quantity of hints (for instance, coming from ancient Egypt) is impressive and stimulating in view of further research.
The art of discovery
Susie J. Lee
JCOM : Journal of Science Communication , 2009,
Abstract: "The Art of Discovery" discusses an ambitious educational program taught by the artist which incorporated locative media, contemporary art, site specificity, and creative work as a proposal for the integration of art, technology and science.
Discovery of Convoys in Trajectory Databases  [PDF]
Hoyoung Jeung,Man Lung Yiu,Xiaofang Zhou,Christian S. Jensen,Heng Tao Shen
Computer Science , 2010,
Abstract: As mobile devices with positioning capabilities continue to proliferate, data management for so-called trajectory databases that capture the historical movements of populations of moving objects becomes important. This paper considers the querying of such databases for convoys, a convoy being a group of objects that have traveled together for some time. More specifically, this paper formalizes the concept of a convoy query using density-based notions, in order to capture groups of arbitrary extents and shapes. Convoy discovery is relevant for real-life applications in throughput planning of trucks and carpooling of vehicles. Although there has been extensive research on trajectories in the literature, none of this can be applied to retrieve correctly exact convoy result sets. Motivated by this, we develop three efficient algorithms for convoy discovery that adopt the well-known filter-refinement framework. In the filter step, we apply line-simplification techniques on the trajectories and establish distance bounds between the simplified trajectories. This permits efficient convoy discovery over the simplified trajectories without missing any actual convoys. In the refinement step, the candidate convoys are further processed to obtain the actual convoys. Our comprehensive empirical study offers insight into the properties of the paper's proposals and demonstrates that the proposals are effective and efficient on real-world trajectory data.
World law  [cached]
Harold J. Berman,Robert W. Woodruff,James Barr Ames
Koers : Bulletin for Christian Scholarship , 1999, DOI: 10.4102/koers.v64i2&3.509
Abstract: In the third millennium of the Christian era, which is characterised by the emergence of a world economy and eventually a world society, the concept of world law is needed to embrace not only the traditional disciplines of public international law, and comparative law, but also the common underlying legal principles applicable in world trade, world finance, transnational transfer of technology and other fields of world economic law, as well as in such emerging fields as the protection of the world's environment and the protection of universal human rights. World law combines inter-state law with the common law of humanity and the customary law of various world communities.
A New Algorithm of Service Discovery Based on DHT for Mobile Application  [cached]
De-gan Zhang,Yu-xia Hu,Dong Wang,Yan-pin Liang
Journal of Networks , 2011, DOI: 10.4304/jnw.6.10.1466-1474
Abstract: In order to solve how to enhance the discovery efficiency and coverage, based on DHT (Distributed Hash Table) and Small World Theory, we put forward a new algorithm of service discovery for mobile application. In traditional DHT discovery algorithm, each node maintains the finger-table that store node information of adjacent node. By using Small-World Theory, we put forward adding a remote node into the finger-table and adding the corresponding remote index. It is different from selecting the remote connection node randomly. We select the remote connection node by calculating local node and it can assure not only the cove range of service discovery but also not increase the length of finger-table, which simplifies the calculation of the finger-table and maintenance work. The simulation proved that the algorithm can reduce the path length of service discovery effectively, improve success rate of service discovery
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