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1.
Entropy (Basel) ; 25(4)2023 Mar 29.
Article in English | MEDLINE | ID: mdl-37190374

ABSTRACT

By using the residual source redundancy to achieve the shaping gain, a joint source-channel coded modulation (JSCCM) system has been proposed as a new solution for probabilistic amplitude shaping (PAS). However, the source and channel codes in the JSCCM system should be designed specifically for a given source probability to ensure optimal PAS performance, which is undesirable for systems with dynamically changing source probabilities. In this paper, we propose a new shaping scheme by optimizing the bit-labeling of the JSCCM system. Instead of the conventional fixed labeling, the proposed bit-labelings are adaptively designed according to the source probability and the source code. Since it is simple to switch between different labelings according to the source probability and the source code, the proposed design can be considered as a promising low complexity alternative to obtain the shaping gain for sources with different probabilities. Numerical results show that the proposed bit-labelings can significantly improve the bit-error rate (BER) performance of the JSCCM system.

2.
Entropy (Basel) ; 25(2)2023 Feb 15.
Article in English | MEDLINE | ID: mdl-36832723

ABSTRACT

In this paper, a joint group shuffled scheduling decoding (JGSSD) algorithm for a joint source-channel coding (JSCC) scheme based on double low-density parity-check (D-LDPC) codes is presented. The proposed algorithm considers the D-LDPC coding structure as a whole and applies shuffled scheduling to each group; the grouping relies on the types or the length of the variable nodes (VNs). By comparison, the conventional shuffled scheduling decoding algorithm can be regarded as a special case of this proposed algorithm. A novel joint extrinsic information transfer (JEXIT) algorithm for the D-LDPC codes system with the JGSSD algorithm is proposed, by which the source and channel decoding are calculated with different grouping strategies to analyze the effects of the grouping strategy. Simulation results and comparisons verify the superiority of the JGSSD algorithm, which can adaptively trade off the decoding performance, complexity and latency.

3.
Entropy (Basel) ; 25(2)2023 Feb 19.
Article in English | MEDLINE | ID: mdl-36832748

ABSTRACT

A key component of the joint source-channel coding (JSCC) scheme based on double low-density parity-check (D-LDPC) codes is the introduction of a linking matrix between the source LDPC code and channel LDPC code, by which the decoding information including the source redundancy and channel state information can be transferred iteratively. However, the linking matrix is a fixed one-to-one mapping, i.e., an identity matrix in a conventional D-LDPC code system, which may not take full advantage of the decoding information. Therefore, this paper introduces a general linking matrix, i.e., a non-identity linking matrix, connecting the check nodes (CNs) of the source LDPC code and the variable nodes (VNs) of the channel LDPC code. Further, the encoding and decoding algorithms of the proposed D-LDPC coding system are generalized. A joint extrinsic information transfer (JEXIT) algorithm is derived for calculating the decoding threshold of the proposed system with a general linking matrix. In addition, several general linking matrices are optimized with the aid of the JEXIT algorithm. Finally, the simulation results demonstrate the superiority of the proposed D-LDPC coding system with general linking matrices.

4.
Zhongguo Gu Shang ; 36(1): 48-54, 2023 Jan 25.
Article in Chinese | MEDLINE | ID: mdl-36653006

ABSTRACT

OBJECTIVE: To assess the clinical effects of percutaneous endoscopic surgery through two different approaches for stable degenerative lumbar spondylolisthesis. METHODS: Sixty-four patients with stable degenerative lumbar spondylolisthesis who underwent percutaneous endoscopic procedures between January 2016 and December 2019 were divided into transforaminal approach group and interlaminar approach group according to surgical approaches, 32 patients in each group. There were 16 males and 16 females in transforaminal approach group, aged from 52 to 84 years old with an average of (66.03±9.60) years, L2 slippage in 4 cases, L3 slippage in 5, and L4 slippage in 23. There were 17 males and 15 females in interlaminar approach group, aged from 46 to 81 years old with an average of (61.38±9.88) years, L3 slippage in 3 cases, L4 slippage in 15, and L5 slippage in 14. Operative time, intraoperative fluoroscopy times, and postoperative bedtime were compared between two groups. Anteroposterior displacement values, interbody opening angles, and the percentage of slippage were measured on preoperative and postoperative 12-month dynamic radiographs. Visual analogue scale (VAS) of low back pain and lower extremity pain, and the Japanese Orthopaedic Association (JOA) score before and after surgery were observed, and clinical effects were evaluated according to the modified MACNAB criteria. RESULTS: All operations were successfully completed, and patients in both groups were followed up for more than 1 year, and without complications during follow-up period. ①There was no significant difference in operation time between two groups(P>0.05). Intraoperative fluoroscopy times were longer in transforaminal approach group than that in intervertebral approach group(P<0.05). Postoperative bedtime was shorter in transforaminal approach group than that in intervertebral approach group (P<0.05).② No lumbar instability was found on dynamic radiography at 12 months postoperatively in both groups. There were no significant differences in anteroposterior displacement values, interbody opening angles, and the percentage of slippage between two groups postoperative 12 months and preoperative 1 day(P>0.05). ③There was no significant difference between two groups in VAS of low back pain at 3 days and 1, 12 months after the operation compared with the preoperative(P>0.05), but the VAS of the lower extremity pain was significantly improved compared with the preoperative(P<0.05). Both of groups showed significant improvement in JOA score at 12 months compared with preoperatively(P<0.05). There was no significant difference in VAS of low back pain, lower extremity pain and JOA scores between two groups during the same period after surgery(P>0.05). According to modified Macnab criteria, excellent, good, fair and poor outcomes were 21, 7, 3 and 1 in transforaminal approach group respectively, and which in intervertebral approach group were 20, 7, 5 and 0, there was no significant difference in clinical effect between the groups(P>0.05). CONCLUSION: Intervertebral approach may reduce intraoperative fluoroscopy times and transforaminal approach can shorten postoperative bedtime, both approaches achieve satisfactory results in the treatment of stable degenerative lumbar spondylolisthesis with no progression of short-term slippage.


Subject(s)
Low Back Pain , Spinal Fusion , Spondylolisthesis , Male , Female , Humans , Middle Aged , Aged , Aged, 80 and over , Spondylolisthesis/surgery , Low Back Pain/surgery , Treatment Outcome , Lumbar Vertebrae/surgery , Spinal Fusion/methods , Retrospective Studies
5.
Cell Biol Int ; 47(7): 1289, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36468208

ABSTRACT

The above article from Cell Biology International, published online on 5 December 2022, on Wiley Online Library (https://doi.org/10.1002/cbin.11940), has been withdrawn by agreement between the journal Editor in Chief, Sergio Schenkman, and John Wiley and Sons Ltd. The withdrawal has been agreed due to a technical error at the publisher that caused the article to be mistakenly published online although it had been rejected due to evidence that the peer review process for this paper was manipulated.

6.
Anat Rec (Hoboken) ; 302(11): 1941-1949, 2019 11.
Article in English | MEDLINE | ID: mdl-31197942

ABSTRACT

Osteosarcoma (OS) is one of the most common malignant bone tumors among children and young adults. Furowanin A (Fur A), one of the active ingredients of Millettia pachycarpa Benth, has been found to exert pro-apoptotic activity in human leukemia cells. This study is designed to evaluate the efficacy of Fur A against OS. The effect of Fur A on cell viability was assessed by Cell Counting Kit-8 (CCK-8) assay. Western blotting and quantitative real-time PCR (qRT-PCR) were performed to determine the protein and mRNA level of sphingosine kinase 1 (SphK1), respectively. To validate the role of SphK1 in the pro-apoptotic activity of Fur A, overexpressing SphK1 vector and siRNA targeting SphK1 were utilized to transfect OS cells. Moreover, an OS xenograft murine model was used to analyze the therapeutic efficacy of Fur A in vivo. Fur A treatment led to a dose-dependent decrease in the number of viable cells. It also exhibited antiproliferative activity and significantly promoted apoptotic cell death in OS cell lines. Our results showed that the anticancer activity of Fur A was associated with downregulation of SphK1 and inactivation of its downstream signaling. The mediatory role of SphK1 was validated when the pro-apoptotic activity of Fur A was significantly blocked by SphK1 overexpression, while SphK1 knockdown sensitized the OS cells to Fur A. We concluded that Fur A can exhibit anti-growth and pro-apoptotic activities in vitro and in vivo in OS by downregulating SphK1. Our study highlights the possibility of utilizing Fur A as a chemotherapeutic agent in the treatment of OS. Anat Rec, 302:1941-1949, 2019. © 2019 American Association for Anatomy.


Subject(s)
Apoptosis , Bone Neoplasms/pathology , Cell Proliferation , Flavonoids/pharmacology , Osteosarcoma/pathology , Phosphotransferases (Alcohol Group Acceptor)/antagonists & inhibitors , Animals , Bone Neoplasms/drug therapy , Bone Neoplasms/metabolism , Female , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Neoplastic , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Osteosarcoma/drug therapy , Osteosarcoma/metabolism , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
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