373 research outputs found

    When can we forecast inflation?

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    This article reassesses recent work that has challenged the usefulness of inflation forecasts. The authors find that inflation forecasts were informative in 1977-84 and 1993-2000, but less informative in 1985-92. They also find that standard forecasting models, while generally poor at forecasting the magnitude of inflation, are good at forecasting the direction of change of inflation.Inflation (Finance) ; Phillips curve

    The 2001 recession and the Chicago Fed National Index: identifying business cycle turning points

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    The initial release of the Chicago Fed National Activity Index (CFNAI) in early 2001 pointed to the very real possibility that the U.S. economy was teetering on the brink of recession. This article quantifies the statistical ability of the CFNAI to act as an early warning indicator of economic recessions. In simulation experiments, the CFNAI performed virtually as well as the statistical model's ideal measure of the business cycle.Recessions ; Economic indicators ; Index numbers (Economics) ; Business cycles

    Candida lipolytica candidemia as a rare infectious complication of acute pancreatitis: A case report and literature review

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    Candida lipolytica candidemia is a rare but an emerging pathogenic yeast infection in humans. It can gain access to the bloodstream through intravascular catheterization, especially through central venous catheters in immunocompromised or critically ill patients during hospitalization. In this report, we present a noncatheter-related C. lipolytica candidemia infection in an 84-year-old man who was admitted due to acute pancreatitis. The possible pathogenesis and management of C. lipolytica candidemia are highlighted. It was an unusual infectious complication of acute pancreatitis. Clinicians should be aware that such an opportunistic pathogen can lead to invasive candidemia infection. In clinical practice, systemic antifungal therapy and the removal of the potentially infected central venous catheter might be recommended for the treatment of C. lipolytica candidemia

    EVALUATION OF RECEIVING ABILITY OF TEENAGE MALE TABLE TENNIS PLAYERS IN TAIWAN

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    The purpose of this study was to evaluate the forehand receiving ability of teenage male table tennis players. Thirty-nine male players consist of skill levels from junior to senior high school students and national squads were selected. This assessment involves three tests: basic control, judgment, and match-like condition simulation. We found under the basic control test, the junior high school players performed poorer in downspin and left-side downspin in the aspect of accuracy (

    THE EFFECTS Of VOLLEYBALL ATTACKING ON SCORE POINTS: A CASE STUDY OF 2014 TVL IN TAIWAN

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    Volleyball is a sport in which team tactical and players' attacking skills determine to score points. Therefore, an effective team tactical is achieved by main spikers' and middle blockers' skills. To name but a few, delayed spike, open spike and back-row spike are main spikers' skills, yet quick spike, and individual time difference attack are associated with middle blockers'. Under this aspect, a case study of male teams of Taiwan Top Volleyball League (TVL) was yield out, which aimed at exploring the effects of team tactical and players attacking skills on score points. The results indicated that the attacking point ratio of main spikers and middle blockers in the champion team was higher than others. This was because the middle blockers gave cover to main spikers as attacking. By doing so, it promoted point ratio to main spikers. Furthermore, it found that to strengthen main spikers and middle blockers' skills would increase team's attacking point ratio

    Cyclooxygenase-2 enhances α2β1 integrin expression and cell migration via EP1 dependent signaling pathway in human chondrosarcoma cells

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    <p>Abstract</p> <p>Background</p> <p>Cyclooxygenase (COX)-2, the inducible isoform of prostaglandin (PG) synthase, has been implicated in tumor metastasis. Interaction of COX-2 with its specific EP receptors on the surface of cancer cells has been reported to induce cancer invasion. However, the effects of COX-2 on migration activity in human chondrosarcoma cells are mostly unknown. In this study, we examined whether COX-2 and EP interaction are involved in metastasis of human chondrosarcoma.</p> <p>Results</p> <p>We found that over-expression of COX-2 or exogenous PGE<sub>2 </sub>increased the migration of human chondrosarcoma cells. We also found that human chondrosarcoma tissues and chondrosarcoma cell lines had significant expression of the COX-2 which was higher than that in normal cartilage. By using pharmacological inhibitors or activators or genetic inhibition by the EP receptors, we discovered that the EP1 receptor but not other PGE receptors is involved in PGE<sub>2</sub>-mediated cell migration and α2β1 integrin expression. Furthermore, we found that human chondrosarcoma tissues expressed a higher level of EP1 receptor than normal cartilage. PGE<sub>2</sub>-mediated migration and integrin up-regulation were attenuated by phospholipase C (PLC), protein kinase C (PKC) and c-Src inhibitor. Activation of the PLCβ, PKCα, c-Src and NF-κB signaling pathway after PGE<sub>2 </sub>treatment was demonstrated, and PGE<sub>2</sub>-induced expression of integrin and migration activity were inhibited by the specific inhibitor, siRNA and mutants of PLC, PKC, c-Src and NF-κB cascades.</p> <p>Conclusions</p> <p>Our results indicated that PGE<sub>2 </sub>enhances the migration of chondrosarcoma cells by increasing α2β1 integrin expression through the EP1/PLC/PKCα/c-Src/NF-κB signal transduction pathway.</p

    Drastic population fluctuations explain the rapid extinction of the passenger pigeon

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    To assess the role of human disturbances in species' extinction requires an understanding of the species population history before human impact. The passenger pigeon was once the most abundant bird in the world, with a population size estimated at 3-5 billion in the 1800s; its abrupt extinction in 1914 raises the question of how such an abundant bird could have been driven to extinction in mere decades. Although human exploitation is often blamed, the role of natural population dynamics in the passenger pigeon's extinction remains unexplored. Applying high-throughput sequencing technologies to obtain sequences from most of the genome, we calculated that the passenger pigeon's effective population size throughout the last million years was persistently about 1/10,000 of the 1800's estimated number of individuals, a ratio 1,000-times lower than typically found. This result suggests that the passenger pigeon was not always super abundant but experienced dramatic population fluctuations, resembling those of an "outbreak" species. Ecological niche models supported inference of drastic changes in the extent of its breeding range over the last glacial-interglacial cycle. An estimate of acorn-based carrying capacity during the past 21,000 y showed great year-to-year variations. Based on our results, we hypothesize that ecological conditions that dramatically reduced population size under natural conditions could have interacted with human exploitation in causing the passenger pigeon's rapid demise. Our study illustrates that even species as abundant as the passenger pigeon can be vulnerable to human threats if they are subject to dramatic population fluctuations, and provides a new perspective on the greatest human-caused extinction in recorded history

    Genome-wide identification of specific oligonucleotides using artificial neural network and computational genomic analysis

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    <p>Abstract</p> <p>Background</p> <p>Genome-wide identification of specific oligonucleotides (oligos) is a computationally-intensive task and is a requirement for designing microarray probes, primers, and siRNAs. An artificial neural network (ANN) is a machine learning technique that can effectively process complex and high noise data. Here, ANNs are applied to process the unique subsequence distribution for prediction of specific oligos.</p> <p>Results</p> <p>We present a novel and efficient algorithm, named the integration of ANN and BLAST (IAB) algorithm, to identify specific oligos. We establish the unique marker database for human and rat gene index databases using the hash table algorithm. We then create the input vectors, via the unique marker database, to train and test the ANN. The trained ANN predicted the specific oligos with high efficiency, and these oligos were subsequently verified by BLAST. To improve the prediction performance, the ANN over-fitting issue was avoided by early stopping with the best observed error and a k-fold validation was also applied. The performance of the IAB algorithm was about 5.2, 7.1, and 6.7 times faster than the BLAST search without ANN for experimental results of 70-mer, 50-mer, and 25-mer specific oligos, respectively. In addition, the results of polymerase chain reactions showed that the primers predicted by the IAB algorithm could specifically amplify the corresponding genes. The IAB algorithm has been integrated into a previously published comprehensive web server to support microarray analysis and genome-wide iterative enrichment analysis, through which users can identify a group of desired genes and then discover the specific oligos of these genes.</p> <p>Conclusion</p> <p>The IAB algorithm has been developed to construct SpecificDB, a web server that provides a specific and valid oligo database of the probe, siRNA, and primer design for the human genome. We also demonstrate the ability of the IAB algorithm to predict specific oligos through polymerase chain reaction experiments. SpecificDB provides comprehensive information and a user-friendly interface.</p
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