2,724 research outputs found

    Spatial Performance Analysis and Design Principles for Wireless Peer Discovery

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    In wireless peer-to-peer networks that serve various proximity-based applications, peer discovery is the key to identifying other peers with which a peer can communicate and an understanding of its performance is fundamental to the design of an efficient discovery operation. This paper analyzes the performance of wireless peer discovery through comprehensively considering the wireless channel, spatial distribution of peers, and discovery operation parameters. The average numbers of successfully discovered peers are expressed in closed forms for two widely used channel models, i.e., the interference limited Nakagami-m fading model and the Rayleigh fading model with nonzero noise, when peers are spatially distributed according to a homogeneous Poisson point process. These insightful expressions lead to the design principles for the key operation parameters including the transmission probability, required amount of wireless resources, level of modulation and coding scheme (MCS), and transmit power. Furthermore, the impact of shadowing on the spatial performance and suggested design principles is evaluated using mathematical analysis and simulations.Comment: 12 pages (double columns), 10 figures, 1 table, to appear in the IEEE Transactions on Wireless Communication

    Taxonomy of the genus Plemyria Hübner (Lepidoptera, Geometridae, Larentiinae)

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    The Holarctic genus of Plemyria comprising two species, rubiginata (Denis et Schiffermüller) and georgii (Hulst), is revised. Redescriptions of adults including the genitalia as well as larvae and pupae are given. The monophyly of the genus is discussed

    The Parathyroid Glands and Parathyroid Surgery in End Stage Renal Failure

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    Background Since the 1850s, parathyroid surgery continues to evolve through improved understanding of the pathophysiology. Dialysis dependant end stage renal failure (ESRF), the major cause of secondary hyperparathyroidism continues to rise in the western world. Other than renal transplantation, parathyroidectomy may provide a substantial cure for longstanding renal hyperparathyroidism in dialysis dependant patients. In 2004, cinacalcet was introduced as an alternative to the surgical management of renal hyperparathyroidism. However, cinacalcet was withdrawn from Australia’s Pharmaceutical Benefits Scheme (PBS) in 2015, as the EVOLVE study failed to demonstrate a statistically significant reduction in the time to death, or non-fatal cardiovascular events in those treated with cinacalcet with renal hyperparathyroidism. This led to a re-emergence in parathyroidectomy. Additionally in our institution, patients who had been on cinacalcet, and subsequently underwent parathyroidectomy because of refractory disease or intolerance to cinacalcet, were noted to experience greater hyperkalaemia and hypocalcaemia in the intraoperative and immediate postoperative period. Aims • To review the engrossing history of the discovery and progression of parathyroid surgery since the 19th century; • To correlate the embryology, anatomy, histology, physiology and pathophysiology of parathyroid glands in end stage renal failure; • To provide up to date review in regards to investigation and the surgical management of renal hyperparathyroidism; • Conduct a cohort study on the association of cinacalcet use with greater likelihood of intraoperative and immediate postoperative hyperkalaemia and hypocalcaemia following parathyroidectomy in renal hyperparathyroidism. Methods Literature reviews utilizing MEDLINE and Cochrane review databases, life science journals and textbooks were utilized. Hospital medical records from The Canberra Hospital were studied to collect data on the cohort case series. Analysis of data was performed using SPSS Statistics and Microsoft Excel. Results Sir Richard Owen is reputed to be the first person to discover the existence of parathyroid glands when examining a rhinoceros in 1852. In the spirit of mortui vivos docent, Captain Charles Martell in the 1930s had significantly increased our understanding of the existence of ectopic locations of parathyroid glands, as well as operative planning. The physiology and pathophysiology of parathyroid glands in chronic renal failure is multifaceted, with a complex interplay between bone, kidneys, intestine, vitamin D, potassium, phosphate and magnesium. There are a range of investigative strategies for localizing parathyroid glands, often yielding greater sensitivity and specificity when utilizing a combination of imaging tools. The choice of operative strategy for parathyroidectomy is often influenced by surgeon’s preference and the institution’s resources, due to paucity of good randomized trials and meta-analysis. Finally, our cohort study has shown that prior cinacalcet use was linked closely with severe intraoperative and immediate postoperative hyperkalaemia, and greater hypocalcaemia compared to control patients who underwent parathyroidectomy for renal hyperparathyroidism. Conclusions The continued inquiry into the basic sciences around renal hyperparathyroidism ensures that we are able to question traditional protocols, and practice the best evidence based medicine. From this, cinacalcet emerged to change the medical and surgical landscape in the treatment of hyperparathyroidism. The results of the cohort study led to development of a protocol for the perioperative management of renal hyperparathyroidism in cinacalcet treated patients requiring parathyroidectomy

    A New Record of Perixera punctata (Lepidoptera: Geometridae) from Korea

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    A sterrhine species, Perixera punctata (Warren) is reported for the first time from Korea. One male and one female were collected from Jeju Island, South Korea. Perixera punctata can be distinguished by the long bipectinate male antennae, the blackish discal dot and a large dark grayish dot on the subcosta of the forewings and a large dark brownish discal dot and blackish undulating postmedial line on the hindwings. In the male genitalia, a long slender valva with two arm-shaped costal processes is a distinguishing character. In the female genitalia, long and medially twisted ductus bursae with a colliculum, and large, ovate corpus bursae with minute dots are distinguishing characters. Diagnosis and description of the species are given with figures of the male and female genitalia

    A Text Mining Approach to the Analysis of BTS Fever

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    K-POP is steadily growing with global competitiveness.The rise of K-POP\u27s popularity has continued to create Korean idol groups. However, many idol groups weredismantled and there islack of measures for overseas advance and success. Therefore, this study aims to analyze the success factors of BTS by focusing onthe text mining techniques. After collecting Twitter\u27s online postings using crawling technique, we will analyzein three text mining techniques: topic modeling, keyword extraction, andterm frequencyanalysis. By analyzing data with three text miningmethods, we willderivehow BTS couldsuccess globallyand form a huge fandom. And with the derived key factors, we will suggest a success strategy based on the analysis results. In contrast to previous studies that were centered on case studiesorinterview, this study has implicationsin that the actual data was collected and analyzed through three text mining techniques

    Examining Online Switching Costs over Search Product and Experience Product Contexts

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    Many Internet vendors have realized the importance of “locking-in” online customers in order to ensure their profitability. For this reason, many researchers have paid attention to the formation of switching costs which acting as a barrier that prevent customers from easily changing from one vendor to another. Erection of switching barriers will represent an important strategy for locking in customers and increasing their willingness to pay price premium. This study aims to examine the relationships among customer satisfaction, perceived value, relative advantage, and switching costs. This study further examines the effect of switching costs on customer’s willingness to pay more. This study collects data and test the research model over two contexts, search product context and experience product context. The empirical results show the key role of switching costs in leading to willingness to pay more and the relationships among the four constructs. The theoretical and practical implications of this study are then discussed

    Cladistic analysis of Therini

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    25 p. : ill. ; 26 cm.Includes bibliographical references (p. 23-24).To test the monophyly of the tribe Therini and resolve the relationship between Therini and Cidariini, 49 morphological characters of 38 species of Thera and related genera were analyzed cladistically. Five taxa from the Cidariini were chosen for outgroup comparisons. Monophyly of the Therini was not supported and the Therini newly synonymized with Cidariini. Five genera, Praethera Viidalepp, Thera Stephens, Pennithera Viidalepp, Heterothera Inoue, and Diathera Choi, are redefined monophyletically, and two new monotypic genera are proposed: Costicoma, n. gen. and Fascilunaria, n. gen. The combination Thera firmata (Hübner) is proposed. Relationships among the ingroup taxa are largely resolved: (Fascilunaria (Heterothera (Thera (Diathera, Pennithera)))). Synapomorphies and a diagnosis of each genus are given, and a key to the ingroup genera is provided
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