• Title/Summary/Keyword: G.729.1

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Audio Stream Delivery Using AMR(Adaptive Multi-Rate) Coder with Forward Error Correction in the Internet (인터넷 환경에서 FEC 기능이 추가된 AMR음성 부호화기를 이용한 오디오 스트림 전송)

  • 김은중;이인성
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.12A
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    • pp.2027-2035
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    • 2001
  • In this paper, we present an audio stream delivery using the AMR (Adaptive Multi-Rate) coder that was adopted by ETSI and 3GPP as a standard vocoder for next generation IMT-2000 service in which includes combined sender (FEC) and receiver reconstruction technique in the Internet. By use of the media-specific FEC scheme, the possibility to recover lost packets can be much increased due to the addition of repair data to a main data stream, by which the contents of lost packets can be recovered. The AMR codec is based on the code-excited linear predictive (CELP) coding model. So we use a frame erasure concealment for CELP-based coders. The proposed scheme is evaluated with ITU-T G.729 (CS-ACELP) coder and AMR - 12.2 kbit/s through the SNR (Signal to Noise Ratio) and the MOS (Mean Opinion Score) test. The proposed scheme provides 1.1 higher in Mean Opinion Score value and 5.61 dB higher than AMR - 12.2 kbit/s in terms of SNR in 10% packet loss, and maintains the communicab1e quality speech at frame erasure rates lop to 20%.

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Serum Biomarkers for Early Detection of Hepatocellular Carcinoma Associated with HCV Infection in Egyptian Patients

  • Zekri, Abdel-Rahman;Youssef, Amira Salah El-Din;Bakr, Yasser Mabrouk;Gabr, Reham Mohamed;El-Rouby, Mahmoud Nour El-Din;Hammad, Ibtisam;Ahmed, Entsar Abd El-Monaem;Marzouk, Hanan Abd El-Haleem;Nabil, Mohammed Mahmoud;Hamed, Hanan Abd El-Hafez;Aly, Yasser Hamada Ahmed;Zachariah, Khaled S.;Esmat, Gamal
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.3
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    • pp.1281-1287
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    • 2015
  • Background: Early detection of hepatocellular carcinoma using serological markers with better sensitivity and specificity than alpha fetoprotein (AFP) is needed. Aims: The aim of this study was to evaluate the diagnostic value of serum sICAM-1, ${\beta}$-catenin, IL-8, proteasome and sTNFR-II in early detection of HCC. Materials and Methods: Serum levels of IL-8, sICAM-1, sTNFR-II, proteasome and ${\beta}$-catenin were measured by ELISA assay in 479 serum samples from 192 patients with HCC, 96 patients with liver cirrhosis (LC), 96 patients with chronic hepatitis C (CHC) and 95 healthy controls. Results: Serum levels of proteasome, sICAM-1, ${\beta}$-catenin and ${\alpha}FP$ were significantly elevated in HCC group compared to other groups (P-value<0.001), where serum level of IL-8 was significantly elevated in the LC and HCC groups compared to CHC and control groups (P-value <0.001), while no significant difference was noticed in patients with HCC and LC (P-value=0.09). Serum level of sTNFR-II was significantly elevated in patients with LC compared to HCC, CHC and control groups (P-value <0.001); also it was significantly higher in HCC compared to CHC and control groups (P-value <0.001). ROC curve analysis of the studied markers between HCC and other groups revealed that the serum level of proteasome had sensitivity of 75.9% and specificity of 73.4% at a cut-off value of $0.32{\mu}g/ml$ with AUC 0.803 sICAM-1 at cut off value of 778ng/ml, the sensitivity was 75.8% and the specificity was 71.8% with AUC 0.776. ${\beta}$-catenin had sensitivity and specificity of 70% and 68.6% respectively at a cut off value of 8.75ng/ml with an AUC of 0.729. sTNFR-II showed sensitivity of 86.3% and specificity of 51.8% at a cut off value of 6239.5pg/ml with an AUC of 0.722. IL-8 had sensitivity of 70.4% and specificity of 52.3% at a cut off value of 51.5pg/ml with AUC 0.631. Conclusions: Our data supported the role of proteasome, sICAM-1, sTNFR-II and ${\beta}$-catenin in early detection of HCC. Also, using this panel of serological markers in combination with ${\alpha}FP$ may offer improved diagnostic performance over ${\alpha}FP$ alone in the early detection of HCC.

The Difference in Chemokine Expression in Airway Epithelial Cells According to the Virulence of Tubercle Bacilli (결핵균 독성 여부에 따른 기도 상피세포의 Chemokine 발현에 관한 연구)

  • Kwon, O-Jung;Kim, Ho-Joong;Kim, Jung-Hee;Kim, Ho-Cheol;Suh, Gee-Young;Park, Jeong-Woong;Park, Sang-Joon;Chung, Man-Pyo;Choi, Dong-Chull;Rhee, Chong-H.
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.4
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    • pp.729-741
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    • 1997
  • Background : We have recently reported that airway epithelial cells can produce RANTES and IL-8 in response to the stimulation of tubercle bacilli suggesting a certain role of airway epithelial cells in the pathogenesis of pulmonary tuberculosis. The pathogenesis of tuberculosis is determined by several factors including phagocytosis, immunological response of host, and virulence of tubercle bacilli. Interestingly, there have been reports suggesting that difference in immunological response of host according to the virulence of tubercle bacilli may be related with the pathogenesis of tuberculosis. We, therefore, studied the expressions and productions of RANTES and IL-8 in airway epithelial cells in response to tubercle bacilli(H37Rv, virulent strain and H37Ra, avirulent strain), in order to elucidate the possible pathophysiology of pulmonary tuberculosis. Methods : Peripheral blood monocytes were isolated from normal volunteers. Peripheral blood monocytes (PBM) were stimulated with LPS($10{\mu}g/ml$), H37Rv, or H37Ra($5{\times}10^5$ bacilli/well) along with normal control for 24 hours. A549 cells were stimulated with supernatants of cultured PBM for 24 hours. ELISA kit was used for the measurement of $TNF{\alpha}$ and IL-$1{\beta}$ production in supernatants of cultured PBM and for the measurement of RANTES and IL-8 in supernatants of cultured A549 cells. Northern blot analysis was used for the measurement of RANTES and IL-8 mRNA expression in cultured A549 cells. Results : $TNF{\alpha}$ and IL-$1{\beta}$ productions were increased in cultured PBM stimulated with LPS or tubercle bacilli(H37Rv or H37Ra) compared with the control. There was, however, no difference in $TNF{\alpha}$ and IL-$1{\beta}$ production between cultured PBM stimulated with H37Rv and H37Ra. RANTES and IL-8 expressions and productions were also increased in cultured A549 cells stimulated with LPS or tubercle bacilli compared with the control. RANTES and IL-8 mRNA expressions were significantly increased in cultured A549 cells stimulated with H37Ra-conditioned media(CM) compared with A549 cells stimulated with H37Rv-CM (p<0.05). However, there was no difference in RANTES and IL-8 productions between A549 cells stimulated with H37Rv-CM and H37Ra-CM. Conclusion : Airway epithelial cells can produce the potent chemokines such as RANTES and IL-8, in response to the stimulation of tubercle bacilli. These results suggest that airway epithelial cells may play a certain role in the pathogenesis of pulmonary tuberculosis. However, the role of airway epithelial cells in the pathogenesis of tuberculosis according to the virulence of tubercle bacilli was not clear in this study.

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