A pitch detector for application in query by humming (QBH) is implemented in this paper. This algorithm is made up of two parts: note segmentation and pitch detection. In the first part, voiced/silence decision is mad...A pitch detector for application in query by humming (QBH) is implemented in this paper. This algorithm is made up of two parts: note segmentation and pitch detection. In the first part, voiced/silence decision is made on each segment of the input signal by a pattern recognition approach, and further, the preparatory note borders are obtained; then, via analysis of the instantaneous energy contour, the adjacent notes that adhere to each other are separated. In the second part, pitch is estimated for all frames contained in a note's duration by an autocorrelation method and the mean of these pitch values is taken as the average pitch of this note. Moreover, in order to remove the effect of formant structure, a nonlinear preprocessing is adopted in the pitch detection part and the autocorrelation function is properly weighted before peak picking. Finally, hummings of several experimenters with different voice characters are recorded to test this pitch detector, whose efficiency and reliability are proved by the results.展开更多
AIM: To investigate the effect of human leukocyte antigen(HLA) DRB1 and DQB1 alleles on the inactive and advanced stages of chronic hepatitis B.METHODS: Patient records at a single institution's hepatology clinic ...AIM: To investigate the effect of human leukocyte antigen(HLA) DRB1 and DQB1 alleles on the inactive and advanced stages of chronic hepatitis B.METHODS: Patient records at a single institution's hepatology clinic were reviewed. Demographic data, laboratory results, endoscopy results, virological parameters, biopsy scores and treatment statuses were recorded. In total, 355 patients were eligible for thestudy, of whom 226(63.7%) were male. Overall, 82(23.1%) were hepatitis B early antigen(HBeAg) positive, 87(24.5%) had cirrhosis, and 66(18.6%) had inactive disease. The presence of DQB1 and DRB1 alleles was determined by polymerase chain reaction with sequence-specific primers. The distribution of the genotyped alleles among patients with cirrhosis and patients with chronic active hepatitis was analyzed.RESULTS: The most frequent HLA DQB1 allele was DQB1*03:01(48.2%), and the most frequent HLA DRB1 allele was DRB1*13/14(51.8%). DQB1*05:01 was more frequent in patients with active disease than in inactive patients(27% vs 9.1%; P = 0.002, Pc = 0.026). DRB1*07 was rare in patients with cirrhosis compared with non-cirrhotics(3.4% vs 16%; P = 0.002, Pc = 0.022). Older age(P < 0.001) and male gender(P = 0.008) were the other factors that affected the presence of cirrhosis. In a multivariate logistic regression analysis, DRB1*07 remained a significant negative predictor of cirrhosis(P = 0.015). A bioinformatics analysis revealed that a polymorphic amino acid sequence in DRB1*07 may alter interaction with the T-cell recognition site.CONCLUSION: This study demonstrates that HLA alleles may influence cirrhosis development and disease activity in Turkish chronic hepatitis B patients.展开更多
文摘A pitch detector for application in query by humming (QBH) is implemented in this paper. This algorithm is made up of two parts: note segmentation and pitch detection. In the first part, voiced/silence decision is made on each segment of the input signal by a pattern recognition approach, and further, the preparatory note borders are obtained; then, via analysis of the instantaneous energy contour, the adjacent notes that adhere to each other are separated. In the second part, pitch is estimated for all frames contained in a note's duration by an autocorrelation method and the mean of these pitch values is taken as the average pitch of this note. Moreover, in order to remove the effect of formant structure, a nonlinear preprocessing is adopted in the pitch detection part and the autocorrelation function is properly weighted before peak picking. Finally, hummings of several experimenters with different voice characters are recorded to test this pitch detector, whose efficiency and reliability are proved by the results.
基金Supported by Internal research funds of Istanbul Technical University,No.36403
文摘AIM: To investigate the effect of human leukocyte antigen(HLA) DRB1 and DQB1 alleles on the inactive and advanced stages of chronic hepatitis B.METHODS: Patient records at a single institution's hepatology clinic were reviewed. Demographic data, laboratory results, endoscopy results, virological parameters, biopsy scores and treatment statuses were recorded. In total, 355 patients were eligible for thestudy, of whom 226(63.7%) were male. Overall, 82(23.1%) were hepatitis B early antigen(HBeAg) positive, 87(24.5%) had cirrhosis, and 66(18.6%) had inactive disease. The presence of DQB1 and DRB1 alleles was determined by polymerase chain reaction with sequence-specific primers. The distribution of the genotyped alleles among patients with cirrhosis and patients with chronic active hepatitis was analyzed.RESULTS: The most frequent HLA DQB1 allele was DQB1*03:01(48.2%), and the most frequent HLA DRB1 allele was DRB1*13/14(51.8%). DQB1*05:01 was more frequent in patients with active disease than in inactive patients(27% vs 9.1%; P = 0.002, Pc = 0.026). DRB1*07 was rare in patients with cirrhosis compared with non-cirrhotics(3.4% vs 16%; P = 0.002, Pc = 0.022). Older age(P < 0.001) and male gender(P = 0.008) were the other factors that affected the presence of cirrhosis. In a multivariate logistic regression analysis, DRB1*07 remained a significant negative predictor of cirrhosis(P = 0.015). A bioinformatics analysis revealed that a polymorphic amino acid sequence in DRB1*07 may alter interaction with the T-cell recognition site.CONCLUSION: This study demonstrates that HLA alleles may influence cirrhosis development and disease activity in Turkish chronic hepatitis B patients.
